-
Designing Small, Simple and EfficientDC to DC Converters Andy
CowellApplications ManagerAsia
Feb 2004
-
MICRELS DC to DC Converters
SMALL SIMPLE and EFFICIENENT
SmallAny DC to DC converter must be as small as possible for the
given applicationSimpleThe DC to DC converter must use as few
external components as possible, without sacrificing
performanceEfficientThe DC to DC converter must be highest
efficiency to minimize any losses
-
The Issues making a DC-DC Small
The biggest component of a DC to DC converter are the Inductor
L, and the Capacitance C
Increasing the switching frequency decreases the size of L and
C, but decreases the Efficiency.
The DC to DC converter must have high speed loop response to
keep the output voltage stable under all conditions with a small
value of L and C
-
The Issues Making a DC-DC SimpleTo make a DC to DC converter
simple all the stability components need to be inside the
Integrated Circuit
The DC to DC converter needs to have high loop speeds without
any external components to keep the L and C small
-
The Issues Making a DC-DC EfficientThe DC to DC converter needs
to have a high switching frequency to keep the L and the C
small
As the switching Frequency increases the switching losses
increase, making it less efficientNote Switching Power Loss in a
MOSFET device used in most DC to DC converters , Is proportional to
Mosfet gate charge ,Q, x Gate Voltage, Vgs, x Frequency, f
A new drive scheme is needed to minimize switching losses
-
Introducing MIC2202
-
2MHz PWM Synchronous Buck Regulator2.3V to 5.5V InputOutput down
to 0.5V 600mA Industrys Smallest Output Components Ultra-fast
transient responseOver 95% efficient Tiny MSOP-10 and 3mm x 3mm
MLF-10L
2.2mH1mF2.2mFPWM Regulator with Worlds Smallest LC
-
MIC2202 BenefitsSmallTiny 2.2mH inductor and 1mF capacitor (or
visa-versa, 1mH inductor and 2.2mF capacitor!! )Few external
components3mm x 3mm MLF package has same pcb area as SOT234x better
thermal performance than SOT23
Low NoiseNo variable frequency modes of operationMIC2202 always
operates in fixed frequency PWM modeIdeal for noise sensitive
applications RF and high speed communications systems
-
MIC2202 BenefitsFAST!Up to 500KHz closed loop band widthFast
transient response allows smaller COUTIdeal for applications that
need fastest responseDAC-controlled VOUT applications such as CDMA
RF Power
Efficient>95% efficientProprietary gate drive minimizes
shoot-through current
-
How the MIC2202 can use small values of L and CThe 2Mhz
switching frequency keeps the L and C Low. To Reduce the L and C to
Only 2.2uH and 1uF output Capacitor, a very high loop bandwidth was
required.Traditionally a tantalum output capacitor is required to
add an extra zero into the loop to help stabilize. The MIC2202 uses
a 1uF ceramic output capacitor to reduce size
A new compensation scheme is needed to achieve high stable
bandwidths
-
MIC2202 Ultra high Bandwidth loop compensationULTRA HIGH BW
-
MIC2202 Performance: L = 2.2mH , COUT = 1mFExcellent Load
Transient ResponseSwitching Waveforms
-
High Efficiency with MIC2204High Efficient drive scheme reduces
switching losses
-
MIC2202 Efficiency
Chart1
80.54785.29689.088
83.39486.13689.399
86.32688.68691.391
88.2690.04892.139
89.33591.00692.887
90.13291.48392.653
90.51591.64592.476
90.81991.95292.492
91.06491.87492.505
91.09791.66592.266
91.2891.76792.067
91.29391.59791.212
91.16691.57391.661
90.93391.2291.182
90.84391.11790.85
90.8890.83890.118
90.20490.18689.813
90.07489.98889.543
90.04789.80989.237
89.84589.5788.899
89.66189.3688.595
89.72489.34288.53
89.19488.7387.804
88.98688.51987.483
88.72688.20487.14
88.55387.96986.782
88.26487.69986.45
88.12287.39786.107
87.8787.11585.745
87.5286.76385.293
87.30586.47784.987
87.10786.20984.627
86.86585.91884.293
86.59285.60383.884
86.3885.35183.529
86.08885.03483.169
85.8284.73482.795
85.51484.38282.365
85.31284.07881.958
84.99983.79881.599
84.78483.581.259
84.50283.18380.839
84.04582.69580.515
83.75882.38680.116
83.51982.12379.562
83.3781.90179.242
82.94781.43878.699
82.68181.13478.297
82.42780.78977.941
82.15280.48777.537
81.88880.277.155
81.60979.85876.664
81.3479.52876.265
81.05679.2175.853
80.75778.83975.389
80.4778.55374.95
80.19278.23474.531
79.90177.86874.097
79.62477.55673.656
L = 2.2mHCOUT = 1mF
4.2Vin
3.6Vin
3Vin
Output Current (A)
Efficiency (%)
Efficiency (1.8Vout)
2.2uH 1uF 1.8V Chart
XYX2Y2X3Y3
0.02489.0880.02485.2960.02480.547
0.03389.3990.03386.1360.03383.394
0.04391.3910.04388.6860.04386.326
0.05392.1390.05390.0480.05388.26
0.06392.8870.06391.0060.06389.335
0.07392.6530.07391.4830.07390.132
0.08392.4760.08391.6450.08390.515
0.09392.4920.09391.9520.09390.819
0.10392.5050.10391.8740.10391.064
0.11392.2660.11391.6650.11391.097
0.12392.0670.12391.7670.12391.28
0.13291.2120.13391.5970.13391.293
0.14391.6610.14391.5730.14391.166
0.15391.1820.15391.220.15390.933
0.16390.850.16391.1170.16390.843
0.17290.1180.17390.8380.17390.88
0.18289.8130.18290.1860.18290.204
0.19289.5430.19289.9880.19290.074
0.20289.2370.20289.8090.20290.047
0.21288.8990.21289.570.21289.845
0.22288.5950.22289.360.22289.661
0.23388.530.23389.3420.23389.724
0.24287.8040.24288.730.24289.194
0.25287.4830.25288.5190.25288.986
0.26287.140.26288.2040.26288.726
0.27286.7820.27287.9690.27288.553
0.28286.450.28287.6990.28288.264
0.29286.1070.29287.3970.29288.122
0.30285.7450.30287.1150.30287.87
0.31285.2930.31286.7630.31287.52
0.32284.9870.32286.4770.32287.305
0.33284.6270.33286.2090.33287.107
0.34284.2930.34285.9180.34286.865
0.35283.8840.35285.6030.35286.592
0.36283.5290.36285.3510.36286.38
0.37283.1690.37285.0340.37286.088
0.38282.7950.38284.7340.38285.82
0.39282.3650.39284.3820.39285.514
0.40281.9580.40284.0780.40285.312
0.41281.5990.41283.7980.41284.999
0.42281.2590.42283.50.42284.784
0.43280.8390.43283.1830.43284.502
0.44280.5150.44182.6950.44184.045
0.45280.1160.45182.3860.45183.758
0.46179.5620.46182.1230.46183.519
0.47279.2420.47281.9010.47283.37
0.48178.6990.48181.4380.48182.947
0.49178.2970.49181.1340.49182.681
0.50177.9410.50180.7890.50182.427
0.51177.5370.51180.4870.51182.152
0.52177.1550.52180.20.52181.888
0.53176.6640.53179.8580.53181.609
0.54176.2650.54179.5280.54181.34
0.55175.8530.55179.210.55181.056
0.56175.3890.56178.8390.56180.757
0.57174.950.57178.5530.57180.47
0.58174.5310.58178.2340.58180.192
0.59174.0970.59177.8680.59179.901
0.60173.6560.60177.5560.60179.624
2.2uH 1uF 1.8V Chart
L=2.2uHCout=1uF
3Vin
3.6Vin
4.2Vin
Output Current (A)
Efficiency (%)
Efficiency 1.8Vout
2202 2R2uH 1uF 1.8Vout Efficie
VinIinVoutIoutEfficiencyVinIinVoutIoutEfficiencyVinIinVoutIoutEfficiency
3.0010.0161.8050.02489.0883.6010.0141.8050.02485.2964.2010.0131.8050.02480.547
3.0010.0221.8050.03389.3993.6010.0191.8050.03386.1364.2010.0171.8050.03383.394
30.0281.8050.04391.3913.6010.0241.8050.04388.6864.2010.0211.8050.04386.326
30.0351.8050.05392.1393.60.031.8050.05390.0484.2010.0261.8050.05388.26
30.0411.8050.06392.8873.60.0351.8050.06391.0064.20.031.8050.06389.335
30.0471.8050.07392.6533.60.041.8050.07391.4834.20.0351.8050.07390.132
2.9990.0541.8050.08392.4763.60.0451.8050.08391.6454.20.0391.8050.08390.515
2.9990.061.8050.09392.4923.60.0511.8040.09391.9524.20.0441.8050.09390.819
2.9990.0671.8040.10392.5053.5990.0561.8040.10391.8744.20.0491.8050.10391.064
2.9990.0741.8040.11392.2663.5990.0621.8040.11391.6654.20.0531.8050.11391.097
2.9980.081.8040.12392.0673.5990.0671.8040.12391.7674.1990.0581.8040.12391.28
2.9980.0871.8040.13291.2123.5990.0731.8040.13391.5974.1990.0631.8040.13391.293
2.9980.0941.8040.14391.6613.5980.0781.8040.14391.5734.1990.0671.8040.14391.166
2.9970.1011.8040.15391.1823.5980.0841.8040.15391.224.1990.0721.8040.15390.933
2.9970.1081.8040.16390.853.5980.091.8040.16391.1174.1990.0771.8040.16390.843
2.9970.1151.8040.17290.1183.5980.0951.8040.17390.8384.1980.0821.8040.17390.88
2.9970.1221.8040.18289.8133.5980.1011.8040.18290.1864.1980.0871.8040.18290.204
2.9960.1291.8040.19289.5433.5970.1071.8040.19289.9884.1980.0921.8040.19290.074
2.9960.1361.8040.20289.2373.5970.1131.8040.20289.8094.1980.0961.8040.20290.047
2.9960.1441.8040.21288.8993.5970.1191.8040.21289.574.1980.1011.8040.21289.845
2.9950.1511.8040.22288.5953.5970.1251.8040.22289.364.1970.1061.8040.22289.661
2.9950.1591.8040.23388.533.5960.1311.8040.23389.3424.1970.1121.8040.23389.724
2.9950.1661.8040.24287.8043.5960.1371.8040.24288.734.1970.1171.8040.24289.194
2.9940.1741.8040.25287.4833.5960.1431.8040.25288.5194.1970.1221.8040.25288.986
2.9940.1811.8030.26287.143.5960.1491.8040.26288.2044.1970.1271.8030.26288.726
2.9940.1891.8030.27286.7823.5950.1551.8040.27287.9694.1960.1321.8030.27288.553
2.9940.1971.8030.28286.453.5950.1611.8030.28287.6994.1960.1371.8030.28288.264
2.9930.2041.8030.29286.1073.5950.1681.8030.29287.3974.1960.1421.8030.29288.122
2.9930.2121.8030.30285.7453.5950.1741.8030.30287.1154.1960.1481.8030.30287.87
2.9930.221.8030.31285.2933.5940.181.8030.31286.7634.1960.1531.8030.31287.52
2.9920.2281.8030.32284.9873.5940.1871.8030.32286.4774.1950.1591.8030.32287.305
2.9920.2361.8030.33284.6273.5940.1931.8030.33286.2094.1950.1641.8030.33287.107
2.9920.2441.8030.34284.2933.5940.21.8030.34285.9184.1950.1691.8030.34286.865
2.9910.2531.8030.35283.8843.5930.2061.8030.35285.6034.1950.1751.8030.35286.592
2.9910.2611.8030.36283.5293.5930.2131.8030.36285.3514.1940.181.8030.36286.38
2.9910.271.8030.37283.1693.5930.221.8030.37285.0344.1940.1861.8020.37286.088
2.990.2781.8020.38282.7953.5920.2261.8030.38284.7344.1940.1911.8020.38285.82
2.990.2871.8020.39282.3653.5920.2331.8020.39284.3824.1940.1971.8020.39285.514
2.990.2961.8020.40281.9583.5920.241.8020.40284.0784.1940.2031.8020.40285.312
2.9890.3041.8020.41281.5993.5920.2471.8020.41283.7984.1930.2081.8020.41284.999
2.9890.3131.8020.42281.2593.5910.2541.8020.42283.54.1930.2141.8020.42284.784
2.9890.3221.8020.43280.8393.5910.2611.8020.43283.1834.1930.221.8020.43284.502
2.9880.3311.8020.44280.5153.5910.2681.8020.44182.6954.1930.2261.8020.44184.045
2.9880.341.8020.45280.1163.5910.2751.8020.45182.3864.1920.2311.8020.45183.758
2.9870.3491.8010.46179.5623.590.2821.8020.46182.1234.1920.2371.8020.46183.519
2.9870.3591.8010.47279.2423.590.2891.8020.47281.9014.1920.2431.8010.47283.37
2.9870.3691.8010.48178.6993.590.2961.8010.48181.4384.1920.2491.8010.48182.947
2.9860.3781.8010.49178.2973.5890.3041.8010.49181.1344.1910.2551.8010.49182.681
2.9860.3881.8010.50177.9413.5890.3111.8010.50180.7894.1910.2611.8010.50182.427
2.9850.3981.8010.51177.5373.5890.3191.8010.51180.4874.1910.2671.8010.51182.152
2.9850.4071.80.52177.1553.5880.3261.8010.52180.24.1910.2731.8010.52181.888
2.9850.4181.80.53176.6643.5880.3341.8010.53179.8584.190.281.8010.53181.609
2.9840.4281.80.54176.2653.5880.3411.8010.54179.5284.190.2861.8010.54181.34
2.9840.4381.80.55175.8533.5880.3491.80.55179.214.190.2921.80.55181.056
2.9830.4491.80.56175.3893.5870.3571.80.56178.8394.190.2991.80.56180.757
2.9830.461.80.57174.953.5870.3651.80.57178.5534.1890.3051.80.57180.47
2.9830.471.7990.58174.5313.5870.3731.80.58178.2344.1890.3111.80.58180.192
2.9820.4811.7990.59174.0973.5860.3811.80.59177.8684.1890.3181.80.59179.901
2.9820.4921.7990.60173.6563.5860.3891.80.60177.5564.1890.3241.80.60179.624
-
MIC2202 Inductor Selection versus Efficiency 2.2mH is optimal
inductor value for small size and high efficiency
MIC2202 works with as low as 1mH inductor for the smallest
size
Up to 4.7mH inductor for reduced ripple current and higher light
load efficiency.
Chart1
20.94099813.6931426.616391
34.7988224.26884812.432345
44.54003132.58446117.568022
51.75310539.28839522.14258
57.30432944.80064826.245512
61.69704849.40228729.944834
65.25033653.30245233.290478
68.18736356.64896436.334217
70.64948359.55333739.120865
72.74314162.09360141.672062
74.54849264.34529144.037792
76.10696466.33097846.200947
77.46935368.10034248.202934
78.67355369.69692250.064346
79.7423471.13819951.797138
80.6935272.44747953.410374
81.54792873.63653654.926254
82.32393674.72755456.345505
83.02019575.72459457.675758
83.64897976.64275458.921383
84.22647977.48597760.096306
84.74865778.26516761.19978
85.22521278.99269962.247822
85.66857979.66621463.233242
86.07348680.29420564.172859
86.45003580.87867765.058769
86.7930681.42513365.902344
87.11619681.93961366.704002
87.41223182.42133367.47197
87.68978182.87103368.198357
87.95019583.29847768.895638
88.18452583.69527469.558784
88.40712784.07312870.191643
88.61520484.4252770.794044
88.80772484.76359671.376991
88.98742785.07656171.932091
89.1547785.37449672.458847
89.30582485.65561772.966064
89.45323985.92279873.456039
89.59288886.18383873.922447
89.7203986.42634674.373993
89.8413786.65539674.809921
89.95078386.87722875.227005
90.05473387.08262675.628075
90.15170387.28548476.015694
90.24066287.47666276.387886
90.32798887.65826476.746033
90.403987.82925477.093575
90.47745587.9874577.422531
90.54850888.14791177.746262
90.61377788.2955778.055664
90.67748388.44026278.352295
90.74189888.5742878.646111
90.80526788.69994478.925995
90.86415988.82600479.197876
90.9276588.94252879.457031
90.98345989.06047179.712257
91.03984189.16635179.960442
91.09328589.26814380.196449
91.14513489.3655480.427666
91.19258989.46266980.648186
91.24081489.54915680.866722
91.28017489.63312581.075737
91.32123689.71423381.277512
91.35987189.78971181.473389
91.3950589.864781.666771
91.42654489.93096281.849274
91.46098389.99736882.027779
91.48802990.0613182.204163
91.51461890.12095682.373337
91.53484390.17411882.536201
91.56082990.23018682.698486
91.57925490.27880982.852173
91.5964290.3275683.004364
91.61354890.37361983.145149
91.62973890.41886983.289871
91.64325790.45729883.425804
91.65519790.49364583.560547
91.66236190.52751983.690613
91.67623990.56546883.814461
91.67759790.59348383.939438
91.68666190.62332984.059387
91.68905690.65281784.173714
91.69541290.67490484.287926
91.69432890.69892184.398964
91.69775490.71904884.505997
91.6954590.73609984.611504
91.6959390.75522684.711624
91.6909190.7703784.809692
91.68775990.78383684.906418
91.68358690.80145385.000198
91.6737990.8066185.085999
91.6711290.81919985.175598
91.66661890.82598985.264755
91.6565790.831285.34449
91.64739290.83663285.425339
91.63650590.83380985.5019
91.62462690.84513185.580521
91.6151590.84387285.654083
91.60008290.84531485.725632
VIN = 3.6VVOUT = 1.8V
4.7uH Inductor
2.2uH Inductor
1uH Inductor
Output Current (mA)
Efficiency (%)
Efficiency vs Inductance
Sheet1
XYX1Y1X2Y2
16.616391113.693142120.9409981000
2.00112.4323452.00124.2688482.00134.798822001
317.568022332.584461344.5400313000
422.14258439.288395451.7531054000
526.245512544.800648557.3043295000
629.944834649.402287661.6970486000
733.290478753.302452765.2503367000
7.99936.3342177.99956.6489647.99968.1873637999
8.99939.1208658.99959.5533378.99970.6494838999
9.99941.6720629.99962.0936019.99972.7431419999
11.00644.03779211.00664.34529111.00674.54849211006
12.00446.20094712.00466.33097812.00476.10696412004
13.00248.20293413.00268.10034213.00277.46935313002
14.00350.06434614.00369.69692214.00378.67355314003
15.00451.79713815.00471.13819915.00479.7423415004
16.00653.41037416.00672.44747916.00680.6935216006
17.00754.92625417.00773.63653617.00781.54792817007
18.0156.34550518.0174.72755418.0182.32393618010
19.01257.67575819.01275.72459419.01283.02019519012
20.01358.92138320.01376.64275420.01383.64897920013
21.01160.09630621.01177.48597721.01184.22647921011
22.00961.1997822.00978.26516722.00984.74865722009
23.00762.24782223.00778.99269923.00785.22521223007
24.00663.23324224.00679.66621424.00685.66857924006
25.00464.17285925.00480.29420525.00486.07348625004
26.00365.05876926.00380.87867726.00386.45003526003
27.00365.90234427.00381.42513327.00386.7930627003
28.00466.70400228.00481.93961328.00487.11619628004
29.00567.4719729.00582.42133329.00587.41223129005
30.00668.19835730.00682.87103330.00687.68978130006
31.00768.89563831.00783.29847731.00787.95019531007
32.00869.55878432.00883.69527432.00888.18452532008
33.00970.19164333.00984.07312833.00988.40712733009
34.00970.79404434.00984.4252734.00988.61520434009
35.00971.37699135.00984.76359635.00988.80772435009
36.00771.93209136.00785.07656136.00788.98742736007
37.00572.45884737.00585.37449637.00589.1547737005
38.00372.96606438.00385.65561738.00389.30582438003
39.00173.45603939.00185.92279839.00189.45323939001
39.99973.92244739.99986.18383839.99989.59288839999
40.99974.37399340.99986.42634640.99989.7203940999
4274.8099214286.6553964289.8413742000
43.00275.22700543.00286.87722843.00289.95078343002
44.00475.62807544.00487.08262644.00490.05473344004
45.00576.01569445.00587.28548445.00590.15170345005
46.00776.38788646.00787.47666246.00790.24066246007
47.00876.74603347.00887.65826447.00890.32798847008
48.00677.09357548.00687.82925448.00690.403948006
49.00477.42253149.00487.9874549.00490.47745549004
50.00277.74626250.00288.14791150.00290.54850850002
5178.0556645188.295575190.61377751000
5278.3522955288.4402625290.67748352000
52.99878.64611152.99888.5742852.99890.74189852998
53.99778.92599553.99788.69994453.99790.80526753997
54.99879.19787654.99888.82600454.99890.86415954998
55.99979.45703155.99988.94252855.99990.9276555999
5779.7122575789.0604715790.98345957000
58.00179.96044258.00189.16635158.00191.03984158001
59.00380.19644959.00389.26814359.00391.09328559003
60.00480.42766660.00489.3655460.00491.14513460004
61.00580.64818661.00589.46266961.00591.19258961005
62.00480.86672262.00489.54915662.00491.24081462004
63.00281.07573763.00289.63312563.00291.28017463002
6481.2775126489.7142336491.32123664000
64.99881.47338964.99889.78971164.99891.35987164998
65.99681.66677165.99689.864765.99691.3950565996
66.99481.84927466.99489.93096266.99491.42654466994
67.99482.02777967.99489.99736867.99491.46098367994
68.99682.20416368.99690.0613168.99691.48802968996
69.99882.37333769.99890.12095669.99891.51461869998
70.99982.53620170.99990.17411870.99991.53484370999
7282.6984867290.2301867291.56082972000
73.00282.85217373.00290.27880973.00291.57925473002
74.00383.00436474.00390.3275674.00391.5964274003
75.00183.14514975.00190.37361975.00191.61354875001
75.99883.28987175.99890.41886975.99891.62973875998
76.99683.42580476.99690.45729876.99691.64325776996
77.99583.56054777.99590.49364577.99591.65519777995
78.99383.69061378.99390.52751978.99391.66236178993
79.99183.81446179.99190.56546879.99191.67623979991
80.98983.93943880.98990.59348380.98991.67759780989
81.9984.05938781.9990.62332981.9991.68666181990
82.99184.17371482.99190.65281782.99191.68905682991
83.99284.28792683.99290.67490483.99291.69541283992
84.99384.39896484.99390.69892184.99391.69432884993
85.99484.50599785.99490.71904885.99491.69775485994
86.99784.61150486.99790.73609986.99791.6954586997
87.99784.71162487.99790.75522687.99791.6959387997
88.99584.80969288.99590.7703788.99591.6909188995
89.99384.90641889.99390.78383689.99391.68775989993
90.99185.00019890.99190.80145390.99191.68358690991
91.98985.08599991.98990.8066191.98991.6737991989
92.98785.17559892.98790.81919992.98791.6711292987
93.98485.26475593.98490.82598993.98491.66661893984
94.98485.3444994.98490.831294.98491.6565794984
95.98785.42533995.98790.83663295.98791.64739295987
96.98985.501996.98990.83380996.98991.63650596989
97.9985.58052197.9990.84513197.9991.62462697990
98.99185.65408398.99190.84387298.99191.6151598991
99.99285.72563299.99290.84531499.99291.60008299992
Sheet1
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
000
Vin=3.6VVout=1.8V
1uH Inductor
2.2uH Inductor
4.7uH Inductor
Output Current (mA)
Efficiency (%)
Efficiency vs Inductance
MIC2202 Light Load Efficiency v
VinIinVoutIoutEfficiencyVinIinVoutIoutEfficiencyVinIinVoutIoutEfficiency
3.7629730.0070531.7563210.0016.6163913.7830.0033871.7546660.00113.6931423.7894480.0022071.7513810.00120.940998
3.7603450.0075181.7563080.00200112.4323453.7805780.0038281.7550910.00200124.2688483.786910.0026611.75220.00200134.79882
3.7577690.0079831.7563890.00317.5680223.7780870.0042791.7552860.00300132.5844613.78440.003121.7525790.00300144.540031
3.7551940.0084491.7563840.00422.142583.7755180.0047341.7554470.00439.2883953.7818030.0035831.7529820.00451.753105
3.752610.0089171.756360.00526.2455123.7729590.0051931.7555430.00544.8006483.7792130.0040481.7532810.00557.304329
3.7499860.0093851.7564320.00629.9448343.7703770.0056551.7555170.00600149.4022873.7766190.0045161.7535910.00600161.697048
3.7474060.0098551.7564510.00733.2904783.7677820.0061191.7556150.00753.3024523.7739690.0049851.7537260.00765.250336
3.7447960.0103261.756430.00799936.3342173.7652240.0065851.7557460.00799956.6489643.7713850.0054561.753870.00799968.187363
3.742160.0107971.75650.00899939.1208653.762630.0070521.755880.00959.5533373.768740.0059281.7539250.00970.649483
3.7395420.0112711.7565050.00999941.6720623.7600120.0075211.755980.0162.0936013.7660980.0064021.7540020.0172.743141
3.73690.0117481.7566010.01100644.0377923.7573720.0079941.756080.01100664.3452913.7634650.0068811.754140.01100674.548492
3.734270.0122221.7566390.01200446.2009473.7547770.0084641.7561840.01200466.3309783.7608130.0073571.7542670.01200476.106964
3.731620.0126971.7566140.01300248.2029343.7521520.0089361.7561890.01300268.1003423.7581610.0078351.7544060.01300277.469353
3.7289820.0131761.7566180.01400350.0643463.7495080.0094111.7562720.01400369.6969223.7554960.0083151.7544660.01400378.673553
3.726340.0136551.7565310.01500451.7971383.7468890.0098871.7563060.01500571.1381993.7528260.0087971.7545550.01500579.74234
3.723670.0141361.7564370.01600653.4103743.744250.0103641.7563650.01600672.4474793.7500980.0092811.7546070.01600680.69352
3.7210040.0146171.7565610.01700754.9262543.7415360.0108421.7564090.01700773.6365363.747410.0097661.7547340.01700781.547928
3.7183160.01511.7565990.0180156.3455053.7389140.0113221.7564530.0180174.7275543.744680.0102521.754780.01801182.323936
3.71560.0155841.7566760.01901257.6757583.736210.0118031.7564810.01901275.7245943.7419990.010741.7548960.01901283.020195
3.7129050.0160691.7566190.02001358.9213833.7335260.0122851.756540.02001376.6427543.7392620.0112291.7549250.02001383.648979
3.7102370.0165531.7566550.02101160.0963063.7308690.0127671.7565830.02101177.4859773.736530.0117171.7550480.02101184.226479
3.7075630.017041.7566920.02200961.199783.7281830.013251.7565420.0220178.2651673.7338090.0122081.755090.0220184.748657
3.7048520.0175261.7567020.02300762.2478223.7254820.0137341.7566270.02300878.9926993.7310880.0126991.7550180.02300885.225212
3.7021390.0180131.7566350.02400663.2332423.7227910.0142191.7566570.02400679.6662143.728340.0131911.7551050.02400685.668579
3.6994310.0185021.7567210.02500464.1728593.7200850.0147061.7567350.02500480.2942053.725610.0136861.7551940.02500486.073486
3.6966520.0189931.7566520.02600365.0587693.7173690.0151931.7566420.02600480.8786773.7228770.0141821.7552670.02600486.450035
3.6939440.0194861.7566980.02700365.9023443.7146710.0156831.7566620.02700381.4251333.7200880.014681.7552660.02700386.79306
3.6911980.019981.7566680.02800466.7040023.7119080.0161741.7566820.02800481.9396133.7173310.0151791.7553170.02800487.116196
3.6884520.0204741.7567350.02900567.471973.709190.0166671.7566980.02900682.4213333.7145480.0156811.7553690.02900687.412231
3.6856870.0209711.7567310.03000668.1983573.7064480.0171621.7567020.03000782.8710333.71170.0161831.7553350.03000787.689781
3.6829290.0214681.75680.03100768.8956383.7037030.0176571.7567680.03100883.2984773.7088950.0166871.7554160.03100887.950195
3.6801550.0219671.7568180.03200869.5587843.70090.0181541.7566930.03200983.6952743.70610.0171931.7553970.03200988.184525
3.6773920.0224671.7568080.03300970.1916433.6981360.0186511.7567220.0330184.0731283.7032740.01771.7554750.03301188.407127
3.6746040.0229671.7568080.03400970.7940443.6953920.019151.7566870.0340184.425273.7004380.0182081.7555240.0340188.615204
3.6718170.023471.7570130.03500971.3769913.6925820.019651.7567550.0350184.7635963.6976030.0187171.7555880.0350188.807724
3.6690190.0239721.7570940.03600771.9320913.6898480.020151.7567290.03600885.0765613.6947890.0192271.7556050.03600888.987427
3.6662150.0244771.7571420.03700572.4588473.687060.0206521.7567370.03700585.3744963.6919680.0197371.7555690.03700689.15477
3.663430.0249821.757180.03800372.9660643.6842150.0211551.7566990.03800485.6556173.6891110.020251.7555070.03800489.305824
3.660610.0254881.7573010.03900173.4560393.6814360.021661.7567220.03900185.9227983.6862520.0207641.7555660.03900289.453239
3.6577910.0259951.7573080.03999973.9224473.6786020.0221651.7568090.03999986.1838383.6833450.021281.7556020.03999989.592888
3.6549370.0265051.7573350.04099974.3739933.6757710.0226731.7568060.04186.4263463.6804460.0217981.7556180.04189.72039
3.6521050.0270171.757440.04274.8099213.6729120.0231831.7567880.04200186.6553963.6775420.0223191.7556750.04200189.84137
3.6492670.0275291.7574790.04300275.2270053.6700780.0236941.7568230.04300286.8772283.6746230.0228411.7556130.04300389.950783
3.6464320.0280431.7574620.04400475.6280753.6672210.0242081.7567990.04400587.0826263.6717280.0233651.7556330.04400690.054733
3.6435840.0285581.7574990.04500576.0156943.6643940.0247221.7568860.04500787.2854843.66880.023891.7556230.04500790.151703
3.6406920.0290741.7574970.04600776.3878863.6615260.0252361.7569020.04600887.4766623.665850.0244171.755630.04600890.240662
3.637830.0295911.7574830.04700876.7460333.6586430.0257531.756930.04700987.6582643.662920.0249451.7556670.04700990.327988
3.6349690.0301091.7575640.04800677.0935753.6557920.0262691.7569550.04800787.8292543.660010.0254731.7556430.04800890.4039
3.6320930.0306281.7575820.04900477.4225313.6529340.0267861.7568420.04900587.987453.6570610.0260021.7556280.04900690.477455
3.6291660.0311471.7575670.05000277.7462623.6500310.0273051.7568920.05000488.1479113.6541290.0265331.7556860.05000490.548508
3.6263050.0316691.7576290.05178.0556643.6471410.0278251.7568840.05100188.295573.6511750.0270651.7556930.05100190.613777
3.6234060.0321921.7576040.05278.3522953.644220.0283471.7569170.05200188.4402623.6482160.0275981.7556760.05200190.677483
3.6205030.0327141.7576130.05299878.6461113.641340.0288691.7568720.05299988.574283.645250.0281311.755710.05299990.741898
3.6175940.033241.7576580.05399778.9259953.6384390.0293951.7568660.05399888.6999443.6422720.0286651.7557150.05399890.805267
3.6146380.0337691.7577030.05499879.1978763.6355260.0299221.7568940.05499988.8260043.6393190.0292011.7556830.05499990.864159
3.6117180.0342981.7576670.05599979.4570313.6325780.0304511.7568790.05688.9425283.636320.0297361.7557160.05690.92765
3.6087690.0348291.7576980.05779.7122573.6296220.0309811.7569310.05700289.0604713.633310.0302741.7557050.05700290.983459
3.6058040.035361.7577330.05800179.9604423.626610.0315131.7568890.05800389.1663513.6303110.0308121.7556970.05800391.039841
3.6028350.0358941.7577020.05900380.1964493.6236510.0320471.7569040.05900489.2681433.62730.0313511.7556620.05900491.093285
3.5998630.0364281.7576890.06000480.4276663.6206640.0325821.7568820.06000589.365543.6242760.0318921.7556960.06000591.145134
3.5968990.0369641.7576740.06100580.6481863.6176960.0331191.7570040.06100789.4626693.6212670.0324341.7556580.06100791.192589
3.5938930.03751.7577170.06200480.8667223.6146940.0336551.756960.06200589.5491563.6182530.0329761.7557360.06200591.240814
3.5909040.0380381.7577650.06300281.0757373.6117450.0341931.7569670.06300389.6331253.6152220.033521.7556820.06300491.280174
3.5879190.0385771.757780.06481.2775123.6087450.0347321.7569610.06400189.7142333.6122170.0340641.7556870.06400191.321236
3.5849080.0391171.7577840.06499881.4733893.6057530.0352721.7569080.06499989.7897113.6092170.0346091.7556770.06591.359871
3.5819160.0396581.7578190.06599681.6667713.6027590.0358151.7569730.06599789.86473.6061350.0351571.7556630.06599891.39505
3.5788910.0402011.7577670.06699481.8492743.5997160.0363611.7569620.06699589.9309623.6030860.0357061.7556630.06699691.426544
3.5758740.0407461.7577320.06799482.0277793.596640.0369081.7569690.06799689.9973683.6000050.0362571.7557020.06799691.460983
3.572830.0412941.7578050.06899682.2041633.5935830.0374561.7569560.06899790.061313.596910.0368121.7556920.06899791.488029
3.5697820.0418441.757810.06999882.3733373.5905210.0380081.7569690.0790.1209563.5938240.0373671.7556610.0791.514618
3.5667460.0423951.7578140.07099982.5362013.5874560.0385611.7569210.07100190.1741183.5907470.0379261.7556510.07100191.534843
3.5636660.0429451.757810.07282.6984863.5843790.0391141.756940.07200290.2301863.5876410.0384841.7556880.07200391.560829
3.5606180.0434981.7578010.07300282.8521733.5812550.0396711.7569280.07300390.2788093.5845220.0390441.7556630.07300491.579254
3.5575540.0440521.7578110.07400383.0043643.5781780.0402281.7569270.07400490.327563.5814090.0396061.755620.07400591.59642
3.5544680.0446081.7577510.07500183.1451493.5750690.0407851.756920.07500290.3736193.5782950.0401681.7556470.07500391.613548
3.5513440.0451641.7578280.07599883.2898713.5719560.0413451.7569910.07690.4188693.5751270.0407321.7556670.07600191.629738
3.5482550.0457231.7578310.07699683.4258043.5688260.0419051.7569490.07699890.4572983.5719890.0412961.7556530.07699891.643257
3.5451310.0462811.75780.07799583.5605473.5657490.0424691.7569560.07799790.4936453.568810.0418641.7556390.07799891.655197
3.5420380.0468411.7577850.07899383.6906133.5625970.0430331.7569170.07899590.5275193.5656780.0424331.7556320.07899591.662361
3.5389280.0474031.7577640.07999183.8144613.5594230.0435991.756980.07999290.5654683.5624720.0430031.7557070.07999391.676239
3.5357820.0479671.7577810.08098983.9394383.5562740.0441671.756930.08099190.5934833.5593510.0435751.7556370.08099191.677597
3.5326630.0485331.7577940.0819984.0593873.5531040.0447371.7569040.08199290.6233293.5561130.044151.7556720.08199291.686661
3.5294580.0491031.7577510.08299184.1737143.5499540.0453091.7569020.08299390.6528173.5529110.0447281.7556620.08299491.689056
3.5262950.0496721.7577420.08399284.2879263.5467370.0458851.7568720.08399490.6749043.5496680.0453071.7556910.08399591.695412
3.5231440.0502441.7577970.08499384.3989643.5435690.0464621.7568940.08499590.6989213.5464730.0458881.7556420.08499691.694328
3.5199760.0508161.7577510.08599484.5059973.5403080.0470421.7568920.08599690.7190483.5432320.0464691.7556610.08599791.697754
3.5167350.0513931.7577840.08699784.6115043.5370540.0476241.7568290.08699990.7360993.5399790.0470551.7556530.08791.69545
3.5135650.0519681.7577420.08799784.7116243.533810.0482061.7568590.08799990.7552263.5367180.047641.7556590.08891.69593
3.5103490.0525441.7577380.08899584.8096923.5305860.0487891.7568670.08899790.770373.533490.0482261.7556150.08899891.69091
3.5071490.0531231.757790.08999384.9064183.5273450.0493731.756820.08999590.7838363.5301770.0488151.7556610.08999691.687759
3.5039230.0537021.7577950.09099185.0001983.5241230.0499571.7568530.09099390.8014533.5269240.0494041.7556660.09099491.683586
3.5006640.0542861.7577610.09198985.0859993.5208220.0505481.7567990.09199190.806613.5236290.0499951.7555660.09199191.67379
3.4974270.0548671.7577460.09298785.1755983.5175110.0511381.7568220.09298990.8191993.5202880.0505891.7556170.09298991.67112
3.4941730.0554531.7578520.09398485.2647553.5142190.0517311.7568230.09398690.8259893.5170340.0511811.7556240.09398791.666618
3.4909260.0560411.7577970.09498485.344493.5108980.0523261.7567510.09498790.83123.5136850.0517811.7556220.09498791.65657
3.4876230.0566321.7577750.09598785.4253393.5075850.0529261.7567780.0959990.8366323.5103540.0523821.7555930.0959991.647392
3.4843420.0572271.7578250.09698985.50193.5042580.0535281.756690.09699190.8338093.5069860.0529851.7555880.09699291.636505
3.4810430.057821.7578550.0979985.5805213.5008830.054131.7568040.09799290.8451313.5035920.0535911.7555940.09799391.624626
3.477730.0584171.7578640.09899185.6540833.4975410.0547351.7567850.09899390.8438723.5002340.0541971.7556170.09899491.61515
3.4743780.0590141.7578130.09999285.7256323.4941570.0553411.7567550.09999590.8453143.4968240.0548071.7555850.09999691.600082
-
MIC2202 Eval Boards2 evaluation boards are available:MIC2202BMM
EV (MSOP-10 package)MIC2202BML EV (3x3 MLF package)
VINVOUT1cm x 1.3cm pcb area
-
MIC2202 Applications802.11 WLAN power supply Camera / video chip
powerCellular phonesPDAsDigital cameras CDMA Dynamic VOUT RF Power
Amp power supplyWireless and DSL modemsStorage drivesCD/DVD ROM
powerPHY core and I/O power supplyASIC / FPGA / DSP / CPU power
supplyPortable applications
-
A High Power Guide to the World of Low Power DC to DC Converters
Andy CowellApplications ManagerAsiaEmail
[email protected] +64 6 378 9799WWW.MICREL.COM
-
Technical Sheet Buck ConverterBuck - Technical Sheet
-
Selector Guides** Most popular
-
MIC2168/9 Small, Simple DC/DC Controllers
-
3VIN to 14.5VINVOUT down to 0.8V500KHz fixed frequency PWM
(MIC2169)1MHz fixed frequency PWM (MIC2168)
Up to 97% efficiencyNo sense resistorOutput over-voltage
protectionAdaptive gate drive
MIC2168/9 Simple Synchronous Buck ControllersVINVOUTRSET
VSW
VIN
VDD
BST
HS
LS
GND
FB
COMP/EN
CS
COUT
0.5 to 1.5KW
1mH
CIN
MIC2169MSOP-10
-
Wide 3V to 14.5 operating rangeWorks from 3.3V, 5V, and 12V
power bussesInternal bootstrap allows single supply operationOther
solutions require split supply operationVOUT range 0.8V to 12V;
IOUT up to 20A Powers the latest ICsAdaptive gate driveAllows up to
97% efficiencyPrevents shoot-through currentHigh-side n-channel
MOSFET current sensingNo current-sense resistor saves cost and
efficiency MIC2168/9 Features
-
Dual mode current limit allows fastest recovery timeHard current
limit until VOUT drops ~16%Hiccup current limit after VOUT drops
below 16% (output short-circuit protection)Output over-voltage
protectionProtects system downstream in fault conditionsHysteretic
transient recovery modeAllows ultra-fast transient responseInternal
soft-startReduces in-rush current Dual function COMP / EN pinPull
this pin to ground for low power shutdown modeFlexible
architectureTantalum capacitor capable for most
applicationsAll-ceramic capacitor capable for smallest size
Electrolytic capacitor capable for lowest cost
MIC2168/9 Features
-
Point-of-Load DC/DC ConversionTelecom/Networking/Datacom
systemsDSP / CPU / FPGA / ASIC power suppliesSet top boxesGraphics
CardsLCD Power SuppliesCable modemsHDD and tape drivesDC/DC SIP
modules
MIC2168/9 Applications
-
MIC2168 (1MHz)Use for smallest size applications1MHz operation
allows smaller external inductorThe trade off with higher frequency
is slightly less efficiency (up to ~3-5%) and lower output
currentMIC2168 is optimal for < ~5A applications
MIC2169 (500KHz)Use for highest current applications that
require the most efficiency
MIC2168 versus MIC2169
-
Typical dc/dc controllers sacrifice efficiency by having a long
fixed dead time between the high- and low-side MOSFET drivers to
prevent shoot-through current. The dead time needs to account for
maximum MOSFET gate capacitance. Though it prevents shoot-through,
efficiency is lost during the low-side MOSFET parasitic diode or
external Schottky diode conduction time.
The MIC2168/9 self-adjusts the dead-time from 30ns to 100ns to
maximize efficiency and prevent shoot-throughMIC2169 Proprietary
Adaptive Gate DriveVINVOUTNoShoot-Through!
VSW
HS
LS
COUT
MIC2169
-
Turn on characteristic, VOUT rise time:
MIC2169 Internal Soft Start2ms rise time Reduces in-rush
current
-
Output OVP protects load in fault conditions eg: solder-bridge
in assembly, or if high-side NFET fails shortLow-side NFET turns on
during output OVP conditionsBlows input fuse to protect the
expensive downstream load
MIC2169 Output Over-Voltage ProtectionOVP TestInductor Current
sinking 1AOVP Test Circuit: Switch High Voltage to MIC2169
Output(1A current limited for benign test)
-
MIC2169 All Ceramic Capacitor CircuitVIN5VVOUT3.3V4A
VSW
VIN
VDD
BST
HS
LS
GND
FB
COMP/EN
CS
COUT
470W
2.5mH
CIN
MIC2169MSOP-10
IRF7821
IRF7821
110
10K
3.16K
100mF
100mF
470pF
8.2K
0.1mF
0.1mF
10mF
SD103B
-
MIC2169 All Ceramic Circuit Performance
Chart1
92.0381272778
95.1473136915
96.9741480611
97.713609934
95.9222878684
eff(%)
ILOAD (A)
Efficiency (%)
5VIN to 3.3VOUT Efficiency
Data
VinIinVoutIouteff(%)
50.35673.2830.592.0
50.69243.294195.1
51.36163.301297.0
52.02943.305397.7
52.75893.308495.9
Plot
Plot
92.0381272778
95.1473136915
96.9741480611
97.713609934
95.9222878684
eff(%)
Iload(A)
Eff(%)
5Vin to 3.3Vout Efficiency
Sheet3
-
MIC2169 Ceramic Circuit Bode PlotSTABLE! 54 Phase Margin29kHz
cross-over frequency
-
MIC2169 7A Eval BoardTOPBOTTOMMIC2169VOUT selector
jumpersN-Channel MOSFETsVOUTVINCINCOUTInductorAvailable on on-line
sample order system1.754.5cm25cm
-
MIC2169 7A General Purpose Eval Board* Light snubbing is
required for super low duty cycle applications to maintain accurate
current limiting (ex: 12VIN to 1VOUT applications) . These
components can be removed for applications with higher duty
cycle.VIN5V to 12VVOUT(Jumper Adjustable)**Shut
Down(optional)(optional)
VSW
VIN
VDD
BST
HS
LS
GND
FB
COMP/EN
CS
470
1N5819
1.2mH
MIC2169MSOP-10
IRF7821
IRF7821
47
100pF
10
10K
Jumper
330mF(x2)
68mF(x2)
0.1mF
4.02K
0.1mF
0.1mF
10mF
SD103B
4.02W
0.1mF
1mF
10mF
100K
2N7002
-
Eval Board Efficiency
MIC2169 Eval Board PerformanceEval Board supports 10A with
airflow, 7A without. Current is limited by the PCB thermals
Chart1
93.541886151282.7561635598
94.974874371988.3663366337
95.946248600291.6609628109
96.092114445292.6331565598
95.773387998592.7915439265
95.008432701192.6342374758
94.747713189792.3147669138
94.340414812391.8178104575
93.471691243491.452991453
92.910699919590.613120554
92.261219792990.051409842
VIN=5V, VOUT=3.3V
VIN=12V, VOUT=3.3V
ILOAD(A)
Efficiency(%)
Data
VINIINIOUTVOUTVIN=12V, VOUT=3.3VVIN=5V, VOUT=3.3V
120.16630.5143.21382.893.5
120.30313.21388.495.0
120.584423.21491.795.9
120.867433.21492.696.1
121.154243.21392.895.8
121.445253.21392.695.0
121.739763.21292.394.7
122.0473.21191.894.3
122.3483.2191.593.5
122.656993.2190.692.9
122.9696103.20990.192.3
50.35310.5143.21393.5
50.676613.21395.0
51.339523.21395.9
52.006233.21396.1
52.68343.21295.8
53.379753.21195.0
54.066863.21194.7
54.763673.2194.3
55.49383.20993.5
56.21593.20892.9
56.952103.20792.3
Plot
Plot
82.756163559893.5418861512
88.366336633794.9748743719
91.660962810995.9462486002
92.633156559896.0921144452
92.791543926595.7733879985
92.634237475895.0084327011
92.314766913894.7477131897
91.817810457594.3404148123
91.45299145393.4716912434
90.61312055492.9106999195
90.05140984292.2612197929
VIN=12V, VOUT=3.3V
VIN=5V, VOUT=3.3V
Iload(A)
Efficiency(%)
MIC2169 Demo board efficiency
Sheet3
-
MIC2169 Eval Board Bode Plot (12VIN to 3.3VOUT )STABLE! 64 Phase
Margin26kHz cross-over frequency
-
Technical Sheet Boost ConverterBoost - Technical Sheet
-
Selector guide- Boost** Most popular
-
MIC2288 Boost RegulatorOEL Driver2.5V to 10VIN1.2MHz fixed
frequency PWM>1A switch currentUp to 34VOUT
Tiny 2x2mm MLF-8L and Thin SOT23-5L package options
-
MIC2288 Boost RegulatorL = 10mHCOUT = 10mF
Chart1
76.744055669376.995931650776.1558842118
81.085423166181.853454918879.5576873341
82.978456464383.962991470482.5543553558
85.345309541683.073433697882.1519679385
85.663031905979.598076340577.9812477403
85.21004543275.839812323275.4504327493
83.6541987908
82.4467392497
79.934176861
VIN = 4.2V
VIN = 3.6V
VIN = 3.2V
Load (A)
Efficiency (%)
15VOUT Efficiency
Sheet1
MIC2288 Bench test report
Fig.1 Transit load test for MIC2288 Load current from 50mA to
150mA For 12V output
Ch1= Vout; CH2=Load current ( L=10uH; Cout=10uF)
Vout =12VL=10uHCout=10uFRb=11K
For Vout=12V and Vin=3.3V, 3.6V and 4.2V, there is stability
limit.
VinIinVoutIoutEff
3.30.67611.990.1509481.1265285996
3.3080.54511.990.1254583.431076179
3.3040.3555711.990.0837285.4443307308
3.30810.2564211.98560.0607285.7948101337
3.30340.1633411.98370.0380884.5734704998
3.3010.1052611.98210.02368781.6834570366
3.60930.09559511.97920.02368182.2185275111
3.60540.1514711.97870.0386584.7772074421
3.6050.2401211.980.0624586.4282375687
3.60730.3425711.98160.0891886.4670605417
3.60340.472511.98370.1214285.4607834517
3.60030.602711.98640.1513883.6213906017
4.2070.4965811.98040.151386.7657869918
4.20310.4005411.97930.1229287.4658208825
4.20150.2883111.97760.0886187.6170179802
4.2040.2055311.97550.062786.9006983083
4.20630.1324411.97410.0394384.7520558414
4.20390.08320911.98870.02396682.1381596968
Vout=15VL=10uHCout=10uF
For 15V, there is no stability limitationRb=11K
VinIinVoutIoutEff
3.30360.8921115.1560.1452774.7058597407
3.30670.536215.1560.0963882.385335293
3.30360.3231115.1590.0595884.6122404888
3.30670.172115.160.0312583.2479518324
3.30190.1071515.1620.01865179.9286582788
3.60790.1151915.1610.02224281.1395162559
3.60070.2558215.1650.051985.4453315294
3.60790.445915.1690.0899684.8231573458
3.30370.7815415.1660.1476886.7442949452
4.20630.629715.1560.1475884.4458215692
4.20140.3468915.1530.0834686.7743146251
4.20260.2335515.1520.0558586.2174574358
4.20090.1098415.1530.02512482.5058114953
For Vout =12V or less, Inductor L looks low value to stability
system
L=4.7uHCout=10uFRb=11K
VinIinVoutIoutEff
5.00980.8763512.0940.300482.75074515160.300412.094
5.00670.6620312.0940.23686.10982920880.23612.094
5.0010.3669812.0940.13286.98505543860.13212.094
5.00120.2179612.1090.07785.53581201810.07712.109
5.00760.09517312.1720.03384.28154604850.03312.172
5.00520.0531289.07490.02585.31727064090.0259.0749
5.00360.132079.09280.06386.68649160930.0639.0928
5.0060.238819.05720.11687.88375267880.1169.0572
5.00620.430599.05550.21188.63857280710.2119.0555
5.00010.871939.05550.4185.16006437180.419.0555
CH1=FB CH2=Inductor Current CH3= SW
Shutdown input current
VinIin
0.0430.9
0.9420.9
1.51
2.11
2.741
3.041
3.41.5
3.842
4.32
VinIin
0.60.003
1.240.23
1.841.485
2.44.9
3.25.334
4.25.8162
L=10uH Cout=30uF Vin=7.6V Vout=15.1V Iout=0.2A
L=10uH Cout=30uF Vin=4.26V Vout=6V Iout193mA System is
stable.
L=10uH Cout=30uF Vin=5.7V Vout=9V Iout230mA System is
stable.
L=10uH Cout=30uF Vin=6.8V Vout=12V Iout203mA System is
stable.
TF
-501.042
01.163
501.205
1001.235
Vin=3.6V
IswVcesat
1.116584
0.924468
0.672336
0.464234
0.264140
TVfb
-501.2157
01.2181
501.217
1001.2135
In Bench test, we found that there is another kind of stability
issue.
So far we have no answer. The unstability looks independent
of the inductor value and load current. This kind unstability
can be
avoid as the Input and the output voltage satisfies as follows
relation:
Rb=11.3K case
VoutVinIout
14.9667.398136
13.1746.533726
11.9515.975124
8.90274.901418
6.31532.97847
Rb=1.02K
VoutVinIout
15.1128.514418.5
13.1547.682116.798
11.0876.641312.82
9.00425.69210.4
7.22644.75658.361
5.72863.89586.628
100 Ohm
VoutVinIout
15.1710Stable
12.0289.862613.916
10.2338.4862611.839
8.15837.00479.44
6.55575.92827.581
5.1334.6395.94
Cout=20uF Rb=1.02K
VoutVinIout
5.76473.95576.68
7.3624.71248.518
9.16395.790710.602
11.79527.071613.644
13.7827.970315.945
15.1578.495817.53
To compare two plots, It looks that to increase the output
capacitor, there is no big improvement.
VinIfb (uA)
30.616
3.80.627
4.310.65
5.210.683
6.510.721
7.610.749
8.710.777
9.410.795
9.90.806
Vin=3.6V
TIfb (uA)
-501.002
00.75
500.579
1000.475
Summary
For MIC2288, there is unstability issue as the input voltage is
closed to
the output voltage. The bench test data gives serveral stable
area plots
All plots give this kind of information that as the feedback
resistor Rb value goes low,
the stable area increases. In the report, there are three group
plots for three values of Rb,
that is, Rb=11K, Rb=1K and Rb=100. We need to base on the
marketing requirment and three group
plots to determine if we need more work on the MIC2280.
L=10uHCout=10uFRb=1K
VinIinVoutIoutEff
3.60490.8646915.0890.1590676.99593165070.1590615.089
3.60420.5988715.1070.1169581.85345491880.1169515.107
3.60170.3715415.1160.0743383.96299147040.0743315.116
3.59910.2327215.1220.04601383.07343369780.04601315.122
3.60810.145515.1310.02761779.59807634050.02761715.131
3.59820.09504615.150.0171275.83981232320.0171215.15
3.20660.1061515.1440.01711776.15588421180.01711715.144
3.20820.1618515.1430.0272879.55768733410.0272815.143
3.20880.2671715.140.04674682.55435535580.04674615.14
3.20550.4512615.1350.07851682.15196793850.07851615.135
3.19940.7104215.1220.1172177.98124774030.1172115.122
3.20490.8162715.1020.130775.45043274930.130715.102
4.20940.08408315.1510.01792876.74405566930.01792815.151
4.2080.125915.1490.02835781.08542316610.02835715.149
4.20520.1834615.1440.04227282.97845646430.04227215.144
4.20570.2898215.1420.06870185.34530954160.06870115.142
4.20460.3626515.140.08627485.66303190590.08627415.14
4.20660.482415.1360.1142485.2100454320.1142415.136
4.20780.639215.1290.1487283.65419879080.1487215.129
4.19940.724915.1220.1659782.44673924970.1659715.122
4.20820.8674615.090.1933779.9341768610.1933715.09
VinIinVoutIoutEff
4.20070.0517112.080.01310172.85765289730.01310112.08
4.20220.0834712.0630.02286278.62531824470.02286212.063
4.20490.1844212.0360.05459984.74287189420.05459912.036
4.20840.3217412.0450.09743486.67528275860.09743412.045
4.2020.4916412.0430.1474985.97931958280.1474912.043
4.19950.8465312.0320.2406381.44185464320.2406312.032
3.60040.06414512.0620.0142174.21639235670.0142112.062
3.60450.1122712.050.02690180.10261956560.02690112.05
3.60430.21655812.0490.05467284.39579374620.05467212.049
3.60830.2980712.0480.0760985.23572058650.0760912.048
3.6090.3820312.0460.09744585.1369461910.09744512.046
3.60970.4689712.0440.1187784.50089951710.1187712.044
3.60960.5738312.0420.1432183.25870279150.1432112.042
3.60550.701612.0340.1709381.31547804750.1709312.034
3.19960.06953312.0650.01353373.38963918530.01353312.065
3.20210.1519812.0620.03271981.09573514480.03271912.062
3.20820.2800612.060.06257983.99692892230.06257912.06
3.20580.4403412.0570.0975383.30151931750.0975312.057
3.20960.6429612.050.137680.347175470.137612.05
3.20320.7925912.0420.1628477.23729795990.1628412.042
VinIinVoutIoutEff
3.20880.0465369.03320.01177671.23734468050.0117769.0332
3.20530.111349.02960.03196480.87415080460.0319649.0296
3.20430.182939.02830.05470584.2587282680.0547059.0283
3.20.310699.02660.09383285.19182416560.0938329.0266
3.20270.429259.02440.1284784.33221307030.128479.0244
3.20770.541779.0220.1597182.91368849590.159719.022
3.20270.741489.01810.2092179.44778346820.209219.0181
3.60130.0354329.04070.009822569.59357191030.00982259.0407
3.60450.0562789.03870.0170375.88167958250.017039.0387
3.60780.1057499.03490.03452181.75004387740.0345219.0349
3.60350.184099.03370.06261585.26863775520.0626159.0337
3.60870.263369.03230.09077186.26703681350.0907719.0323
3.60110.432269.02950.1478785.77555652190.147879.0295
3.60950.697539.02320.229782.32119038710.22979.0232
4.20720.0325379.04550.01048869.3034079890.0104889.0455
4.20760.0663159.04130.02452879.47797566850.0245289.0413
4.20080.118439.03870.04608283.72276392010.0460829.0387
4.20730.177099.03770.07114186.29395391770.0711419.0377
4.20490.287129.03610.1170787.62086364950.117079.0361
4.20820.473229.03250.1918287.00463584990.191829.0325
4.20510.704759.02650.2777884.60751652860.277789.0265
Sheet1
Load Current (A)
Efficiency (%)
Vin=3.3V Efficiency vs Load
Sheet2
Load Current (A)
Efficiency (%)
Vin=3.6V Efficiency vs Load
Sheet3
Load Current (A)
Efficiency (%)
Vin=4.2V Efficiency vs Load
Load Current (A)
Efficiency (%)
Vin=3.3V Efficiency vs Load
Load Current (A)
Efficiency (%)
Vin=3.6V Efficiency vs Load
Load Current (A)
Efficiency (%)
Vin=4.2V Efficiency vs Load
Load (A)
Efficiency (%)
Vin=5, Vout=12V Efficiency
Load (A)
Efficiency (%)
Vin=5, Vout=9V efficiency
Vin(V)
Iin (uA)
Shutdown current vs Vin
Vin(V)
Quiescent Current (mA)
Quiescent Current vs Vin
Temperature (C)
Frequency (MHz)
Frequency vs. Temperature
Switch Current (A)
Vcesat (mV)
Switch saturation Voltage (Vin=3.6V)
Temperaturre (C)
Feedback voltage (V)
Feedback Voltage vs. Temperature
Stable Area
Vout (V)
Vin
Stable area is below the curve
Stable Area
Vout(V)
Vin(V)
Stable area is below the curve
Stable Area
Vout (V)
Vin (V)
Stable area is below the curve
Stable Area
Vout (V)
Vin (V)
Stable area is below the curve (C=20uF; Rb=1K)
Stable area
Vout (V)
Vin (V)
Stable area is below the curve (C=10uF; Rb=1K)
Vin (V)
Ifb (uA)
Ifb vs. Vin
Temperature (C)
Ifb (uA)
Ifb vs Temperature
Load (A)
Efficiency (%)
Efficiency vs Load (Vin=3.6; Vout=15V)
Load (A)
Efficiency (%)
Efficiency vs Load (Vin=3.2V; Vout=15V)
Load (A)
Efficiency (%)
Efficiency vs load (Vin=4.2V; Vout=15V)
Load (A)
Vout (V)
Load line regulation (Vin=3.6V)
Load (A)
Vout (V)
Load line regulation (Vin=3.2V)
Load (A)
Vout (V)
Load line regulation (Vin=4.2V)
Load (A)
Efficiency (%)
Efficiency vs load (Vin=4.2V; Vout=12V)
Load (A)
Efficiency (%)
Efficiency vs Load (Vin=3.6V; Vout=12V)
Load (A)
Efficiency (%)
Efficiency vs load (Vin=3.2V; Vout=12V)
Load (A)
Vout (V)
Load line regulation Vin=4.2V
Load (A)
Vout (V)
Load line regulation Vin=3.6V
Load (A)
Vout (V)
Load line regulation (Vin=3.2V)
Load (A)
Efficiency (%)
Efficiency vs load (Vin=3.2V; Vout=9V)
Load (A)
Efficiency (%)
Efficiency vs load (Vin=3.6V; Vout=9V)
Load (A)
Efficiency (%)
Efficiency vs Load (Vin=4.2V; Vout=9V)
Load (A)
Vout (V)
Load line regulation Vin=3.2V
Load (A)
Vout (V)
Load line regulation Vin=3.6V
Load (A)
Efficiency (%)
Load line regulation (Vin=4.2V)
Load (A)
Vout (V)
Load line regulation Vin=5V; Vout=12V
Load (A)
Vout (V)
Load line regulation Vin=5V; Vout=9V
VIN = 4.2V
VIN = 3.6V
VIN = 3.2V
Load (A)
Efficiency (%)
15VOUT Efficiency
- MIC2288 Boost RegulatorVOUT
- MIC2288 Load Transient Performance12VOUT50mA150mAL = 10mHCOUT =
10mFVOUT
-
MICREL DC to DC ConvertersFor Small Simple Efficient DC to DC
Converters
Think MICREL
