VINH 0.7 × VDRIVE V VINL +0.3 × VDRIVE V IIN ±0.01 ±1 µA VIN = 0 V
VDRIVE
CIN 3 3 pF
VOH VDRIVE − 0.3 V VDRIVE < 1.8
VDRIVE − 0.2 V VDRIVE ≥ 1.8 VOL 0.4 V ±0.01 ±1 µA 3 8 pF
−40 +125 ±1 ±2 °C TA = −40°C +85°C
±1 ±3 °C TA = +85°C +125°C 0.25 °C LSB
1 t2 + 16 × tSCLK VIN0VIN71
100 TSENSE
10 KSPS TSENSE1
= 0 VVDRIVE VDD 2.8 3 3.6 V VDRIVE 1.65 3 3.6 V ITOTAL
6 VDD = 3.6 V, VDRIVE = 3.6 V () 5.8 6.3 mA () 4.1 4.6 mA 2.7 3.3
mA 1 1.6 TA = −40°C +25°C
10 TA = −40°C +125°C 7
() 17.4 18.9 mW VDD = 3 V, VDRIVE = 3 V 22.7 mW
() 14.8 16.6 mW 9.8 11.9 mW 3.6 5.8 TA = −40°C +25°C
36 TA = −40°C +125°C
1 “” 2 (dB)FSR0.5 dB 3 4 25°CVREF 5 VREF(“”) 6 ITOTALVDDVDRIVE 7
VDD = VDRIVE = 3.6 V
AD7298
VDD = 2.8 V3.6 VVDRIVE = 1.65 V3.6 VVREF = 2.5 VTA =
−40°C125°C
tr = tf = 5 ns1090VDRIVE1.6V
2 TMINTMAX /
tCONVERT t2 + (16 × tSCLK) μs()
820 ns() ADCVIN0VIN7fSCLK = 20 MHz 100 μs()
fSCLK 1 50 kHz()
20 MHz()
t3 1 15 ns() CSDOUT
SCLKt4 1
35 ns() VDRIVE= 1.65 V3 V 28 ns() VDRIVE= 3 V3.6 V t5 0.4 × tSCLK
ns() SCLK
t6 0.4 × tSCLK ns() SCLK
t7 1 14 ns() SCLKDOUT
t8 1 16/34 ns(/
1 DOUT15 pF
3
GND1 −0.3 V 3 V
GND −0.3 V VDRIVE + 0.3 V GND −0.3 V VDRIVE + 0.3 V
VREF GND1 −0.3 V +3 V GND1 GND −0.3 V +0.3 V ±10 mA −40°C +125°C
−65°C +150°C 150°C
260(+0)°C ESD 3.5 kV
ESD
14
13
12
1
3
4
DOUT
NOTES 1. THE EXPOSED METAL PADDLE ON THE BOTTOM
OF THE LFCSP PACKAGE SHOULD BE SOLDERED TO PCB GROUND FOR PROPER
FUNCTIONALITY AND HEAT DISSIPATION.
5.
VIN3, VIN4, VIN5, VIN6, VIN7, VIN0, VIN1, VIN2
AD72988 0 V2.5 VGND1
6 GND1 AD7298GND1 GND1GND( )0.3 VVREF10 μF
7 VREF /2.5 V 10 μFGND1 2.0 V2.5 V
8 DCAP (1 μF)LDO
9 GND AD7298GND ()0.3 VDCAPVDD GND
10 VDD (2.8 V3.6 V)10 μF100 nFGND
11 CS
12 TSENSE_BUSY
13 DIN
2.
16 VDRIVE GND 1.65 V3.6 VVDD0.3 V
17 PD/RST 1 ns 100 nsAD7298 0 V
EPAD EPAD LFCSPPCB
–120
–100
–80
–60
–40
–20
0
FREQUENCY (kHz)
A M
P L
IT U
D E
350 400 450 500
VDD = VDRIVE = 3V fSAMPLE = 1.17647MHz fIN = 50kHz fSCLK = 20MHz
SNR = 72.621 THD = –82.562
08 75
4- 03
TA = 25°C VDRIVE = 3V VREF = 2.5V VDD = 3 V
08 75
4- 01
TA = 25°C VDRIVE = 3V VREF = 2.5V VDD = 3 V
08 75
4- 01
IN L
(L S
INL MAX
INL MIN
08 75
4- 01
IN L
(L S
2
3
4
5
6
7
8
9
10
11
12
E F
F E
C T
IV E
N U
M B
E R
O F
B IT
Rev. B | Page 10 of 24
0
0.5
1.0
1.5
2.0
2.5
3.0
0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
CURRENT LOAD (mA)
T E
M P
E R
A T
U R
E R
E A
D IN
P S
R R
(d B
7
70
75
80
85
90
95
100
105
110
0 50 100 150 200 250 300 350 400 450 500 550
IS O
LA T
IO N
S IN
A D
10. (50°C) 13. (SINAD)
11. (PSRR) 14. SINAD
AD7298
–1.5
–1.0
–0.5
0
0.5
1.0
1.5
2.0
)
–40 –25 –10 0 10 20 25 30 35 45 60 85 105 125
08 75
4- 03
4
10
11
12
13
14
15
16
17
18
19
0 100 200 300 400 500 600 700 800 900 1000
P O
W E
T O
TA L
C U
R R
E N
VDRIVE = 3V+85°C +105°C +125°C
08 75
4- 03
C U
R R
E N
16. (THD) 19.
AD7298
(SINAD)
(fS/2)
( 0 0 … 0 0 0 ) ( 0 0 … 0 0 1 ) (
GND1+1 LSB)
AD7298
D1
1 MSPS
AD7298ADC
2.5 V(DCAP)LDO300mV
10 mA
RC
AD7298
VREF/4096AD7298
111...111
111...110
111...000
011...111
000...010
000...001
000...000
A D
C C
O D
CS
SCLK
DOUT
DIN
CONVERSION RESULT FOR CHANNEL 4
CONVERSION RESULT FOR CHANNEL 1
INVALID DATAINVALID DATA
NO WRITE TO THE CONTROL REGISTER
08 75
4- 00
CS
SCLK
DOUT
DIN
CONVERSION RESULT FOR CHANNEL 1
CONVERSION RESULT FOR CHANNEL 5
CONVERSION RESULT FOR CHANNEL 2
INVALID DATAINVALID DATA
DATA WRITTEN TO CONTROL REGISTER CH 1 AND 2 SELECTED
CS
SCLK
DOUT
DIN
08 75
4- 01
DOUT
1
CS
CS25
AD7298
CS
CS
SCLK
DOUT
DIN
CONVERSION RESULT FOR CHANNEL 0
CONVERSION RESULT FOR CHANNEL 1
INVALID DATAINVALID DATA
NO WRITE TO THE CONTROL REGISTER
NO WRITE TO THE CONTROL REGISTER
DATA WRITTEN TO CONTROL REGISTER CH 0, CH 1, AND CH 2
SELECTED: REPEAT = 1
CONVERSION RESULT FOR CHANNEL 0
CONVERSION RESULT FOR CHANNEL 2
NO WRITE TO THE CONTROL REGISTER
NO WRITE TO THE CONTROL REGISTER
NO WRITE TO THE CONTROL REGISTER
08 75
4- 01
CSVIN1CS
CS
SCLK
DOUT
DIN
11
4 CHANNEL ADDRESS BITS + CONVERSION RESULT
08 75
4- 01
INVALID DATA INVALID DATA
PART IS IN PARTIAL POWER DOWN
WRITE TO CONTROL REGISTER, PPD = 0.
CONTROL REGISTER CONFIGURED TO POWER UP DEVICE.
SELECT ANALOG INPUT CHANNELS FOR CONVERSION. THE NEXT CYCLE WILL
CONVERT THE FIRST CHANNEL
PROGRAMMED IN THIS WRITE OPERATION.
PART BEGINS TO POWER UP ON CS RISING EDGE.
THE PART IS FULLY POWERED UP ONCE THE WRITE TO THE CONTROL REGISTER
IS COMPLETED.
AD7298 CONVERTING CHANNEL 1 NEXT CYCLE HAS CHANNEL 1
RESULT AVAILABLE FOR READING.
28.
29.
AD7298
AD7298PPD1
AD7298
“”16
DINAD7298
CS
tQUIETCS
AD7298
AD7298
CS
DOUT
DIN
t2
t3
ADD2
B
08 75
4- 01
16SCLKCS
CS
SCLK
DOUT
DIN
TEMPERATURE SENSOR RESULTPREVIOUS CONVERSION RESULT
CONFIGURE CONTROL REGISTER FOR NEXT CONVERSION
DATA WRITTEN TO CONTROL REGISTER CH TSENSE SELECTED
TSENSE_BUSY THE TEMPERATURE
CONVERSION IS COMPLETED
08 75
4- 01
CS