IC BA5979S Datasheet

BA5979S Optical disc ICs

4-channel BTL driver for CD players BA5979S The BA5979S is 4-channel BTL actuator and motor driver IC for CD-ROM players. It has three interface filters and a pulse control PWM driver, while the spindle driver is separately controlled. The small BA5979S footprint includes a 5V regulator (external PNP Tr required) and a built-in reset circuit for maximum miniaturization of applications. zApplications CD players, CD-ROM drives, MD players and other optical disc devices zFeatures 1) Four-channel BTL driver 2) Three channels are PWM input direct-coupled type (built-in primary filter) 3) Wide dynamic range (5.6V (typical) at PreVCC=8V, PowVCC=8V, and RL=8) 4) Internal thermal shut-down circuit 5) Internal 5V regulator (requires external PNP transistor) 6) Reset output pin 7) Output current can be muted using an external mute pin zAbsolute maximum ratings (Ta = 25C)

Parameter Symbol Limits Unit

Power supply voltage

Power dissipation

Operating temperature

Storage temperature

VCC

Pd

Topr

Tstg

13.5

1.7*

-35~+85

-55~+150

V

W

* Values when the IC is unmounted

C

C

zRecommended operating conditions (set the power-supply voltage according to the power dissipation)

Parameter Symbol Limits Unit

Pre-block power supply voltage

Power-block power supply voltage

PreVCC

PowVCC

6.0~13.2

6.0~PreVCC

V

V


zBlock diagram

INTERFACE

F R

INTERFACE

INTERFACE

REGULATORT. S. D

MONITOR

THERMALSHUTDOWN

LEVELSHIFT

F R

F R

POWVCC

PreVCC POWVCC

POWVCC

50k

50k

50k

50k

R

R

F

10k

10k

19k

100

10k

MUTE

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

25 24 23 22 21 2032 31 30 29 28 27 26 19 18 17

F

Vref

D D D D

F

R

D D DD

+ |+ -

T.S.D. : Thermal Shut DownD: Drive Buffer: The unit of resistance:

zPin description

Pin. No Pin Name Function

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

CH1FIN

CH1RIN

CH2FIN

CH2RIN

GND

VrefOUT

VrefIN

CAPAIN1

CAPAIN2

POWVCC

RESET

CH2OUTR

CH2OUTF

CH1OUTR

CH1OUTF

GND

CH 1 PWM forward input

CH 1 PWM reverse input



GND

Internal reference voltage output

Internal reference voltage input

External capacity for CH 1


Power stage power supply voltage (CH 1,2)

Reset output

CH 2 reverse output

CH 2 forward output

CH 1 reverse output

CH 1 forward output

Substrate GND

Pin. No Pin Name Function

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

CH4OUTF

CH4OUTR

CH3OUTF

CH3OUTR

MUTE

POWVCC

PreVCC

CAPAIN3

CH3RIN

CH3FIN

CH4IN

CH4IN

CH4BIAS

REG-B

REGOUT

SUB

CH 4 forward output

CH 4 reverse output

CH 3 forward output

CH 3 reverse output

Mute

Power-stage power supply voltage (CH 3,4)

Pre-stage power supply voltage




CH 4 input

CH 4 gain control

CH 4 bias input

Regulater ext. Tr base connection

Constant voltage output(ext. Tr collector)

Substrate GND

Note: Positive output and negative output are the polarities with respect to the input


zElectrical characteristics (unless otherwise noted, Ta=25C, VCC=8V, and RL=8

Parameter Symbol Min. Typ. Max. Unit Conditions

Circuit current

Bias pin voltage

Bias voltage fluctuation

Mute off voltage

Mute on voltage

H level input voltage

L level input voltage

H level input current

L level input current

Output offset voltage

Maximum output amplitude

Constant current value

Capacitance for internal integration

Current pulse delay time 1

Current pulse delay time 2

Current pulse delay time difference

Driver block linearity

Input bias current

Output offset voltage

Maximum output amplitude

Voltage gain

Output voltage

Output load variation

Reset ON threshold voltage

Reset ON output voltage

IQ

VBIAS

VBIAS

VMON

VMOFF

VIH

VIL

IIH

IIL

VOO

VOM

ICONST

C

tr

tr

tr-f

LIN

IB

VOO4

VOM4

GVC

VreSg

VRL

VTHR

VRON

-

3.70

-30

2.0

-

2.4

-

170

-20

-30

4.4

17

-

-

-

-160

90

-

-50

5.0

8.5

4.75

-50

-

-

17.0

4.00

-

-

-

-

-

310

-

-

5.0

25

25

0.30

0.30

-

100

10

-

5.6

11.0

5.00

0

4.0

-

25.0

4.30

30

-

0.5

-

0.5

450

10

30

5.6

33

-

1

1

160

110

300

50

-

13.5

5.25

10

-

0.5

mA

V

mV

V

V

V

V

A

A

mV

V

A

pF

s

s

ns

%

nA

mV

V

dB

V

mV

V

V

No load

1mA Source, Sink

VIN=5V

VIN=0V

FIN=5V, RIN=0V

Rise time

Rise time

VIN=Vref0.5, 1, 1.5V *1

IL=100mA

IL=0~200mA

By regulator voltage

Connect to 5V at 10k

Not designed for radiation resistance * 1 When VIN=Vre0.5, V0=V01, when VIN=Vref1.0V, V0=V02, and when VIN=Vref1.5V, V0=V03, then LIN=(V03-V02)/(V02-V01) x 100[%]


zI/O circuit

ch1~3

1,3,26pin

17k

ch1~3

2,4,25pin

17k

7.3k

17~20pin

12~15pin

20k

10k

10k

7pin50k

50k

21pin

50k

50k6pin

ch1~3 8,9,24pin

17k 31pin

30pin

50k

20k

10k10k

10k23k

36k

28pin

27pin29pin

100

10k

75k

11pin

F-side driver-input pin

R-side driver input pin

Driver-output pin

Mute pin

External C

APA pin

CH

4 input pin

Inter.reference.voltage pinInter.ref.voltage output pin

Tr base connction to regulater output-pin

CH

4 bias pin reset output pin


zMeasurement circuit

F

REGULATORT. S. D

MONITOR

THERMALSHUTDOWN

LEVELSHIFT

F R

F R

POWVCC

Vo

RL

PreVCC

PreVCC

PowVCC

POWVCC

POWVCC

50k

50k

R

R

F

10k

ILVreg

Fig.1

10k

19k

100

10k

MUTE

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

25 24 23 22 21 2032 31 30 29 28 27 26 19 18 17

F

D D D

F

R

D D DD

R

Vref

D

Vo

RL10k

5V

VrefVrefVref

Iref

1 F

+

IC IC

IN INPF PR

Vf Vr

Ir

PR

F

F R INTFOUT

ch1 F R INTFOUT

ch2

PF

A

R

A

IPIL

SW

ICON

Vref

Vref

100Moni

INTFOUT

A

PreVCC

Vb

Vb4

VsinIb1

M

ch3

F RINTFOUT Ipow VM RL

VoIpre A ARL

Vo4

VV

V V V V

V VV

V

V

V

-+

+ -+ |

INTERFACE

INTERFACE

INTERFACE


zCircuit operation

1. Ch 1 ~ CH 3 driver (all drivers except spindle driver)

I2

Fig.2

I1

100k

SW1

SW2

BUF2

BUF125pF

OUT1

OUT2

INTERFACEF

R

A

F

L

L

H

H

R

L

H

L

H

SW1

OFF

OFF

ON

OFF

SW2

OFF

ON

OFF

OFF

H: More than 2.4VL: Less than 0.5V

Fig.3

5V

0V

0V

Input

F (R)

R (F)

OUT2(1)

OUT1(2)

1V /s

Fig.4

VrefOutput

0V

Fig. 3 shows the input from the digital servo IC. When the IC receives a forward signal (H level greater than 2.4V), SW1 turns on. When the IC receives a reverse signal, SW2 turns on. (Fig. 2) When a switch is on, constant current I1 flows into the RC and an integrated waveform is generated based on the DUTY of the input waveform. BTL output is then gained through BUF1 and BUF2. (Fig. 4) When H level is kept with forward or reverse inputs, the DC voltage at point A is: I1xR 2.5V 2.5V (-2.5V for reverse side) The voltage is measured with respect to Vref and the voltage between output pins is 5V. The time constant is set to: RC=2.5s To increase the time-constant value, connect an external capacitor between point A (pins 8, 9, and 24) and Vref. In Fig. 2, I1 and I 2 show the constant current value (ICONST) listed in the electrical characteristics table.

2. Channel 4 driver (Spindle driver) The input signal is expected to be an oscillation around the BIAS point. The output of the pre-stage amplifier centered at the BIAS voltage applied to pin 29 is converted by the level-shift circuit to positive and negative oscillations centered at Vref. The output of the level-shift circuit is BTL through the buffer amplifier. The gain can be varied by connecting an external resistor to pin 28.


3. The relationship between mute and reset output

Function

Regulator voltage drop

Thermal shut down

Mute (21pin)

Mute operation

Turns on for all

conditions

Reset output

"H" "L"

"H" "L"

No change

a) Regulator voltage drop If the regulator voltage falls to or below 4.0V (typical), the remaining output turns Low and muting occurs. If the voltage then rises to 4.2V (typical), the remaining output turns High and muting is disabled.

b) Thermal shutdown When the chip temperature exceeds 175C (typical), muting occurs and the reset output turns Low. When the chip temperature falls below150C (typical), muting is disabled and the remaining output turns High.

c) Mute (pin 21) If the voltage of the MUTE pin (pin 21) is open or falls to 0.5V or below, muting occurs and the remaining output remains unchanged.


zApplication example

DIGITAL

SERVO

Fig.5

TRACKINGERROR

OUT

FOCUSERROR

OUT

FR

THE

RM

AL

SH

UTD

OW

N

RE

GU

LATO

RT.

S.D

MO

NIT

OR

LEV

EL

SH

IFT

FR

FR

50k

50k

R

R

F

10k

10k

19k

100

10k

MU

TERESET OUT

12

34

56

78

910

1112

1314

1516

2524

2322

2120

3231

3029

2827

2619

1817

F

DD

DD

FR

DD

DD

TRACKINGCOIL

FOCUSCOIL

10k 5VPOWVCC1

0.1 F

FOR

WA

RD

RE

VE

RS

E

FOR

WA

RD

RE

VE

RS

E

SLEDOUT

MU

TE

FOR

WA

RD

RE

VE

RS

E

BIA

S2.

5VS

PIN

DLE

OU

T

M

M

POWVCC2

SPINDLEMOTOR

SLEDMOTOR

0.1 F

PreVCC0.1 F

PreVCC

2SB1132

5VOUT

22 F

|

+

-+

+

INTE

RFA

CE

INTE

RFA

CE

INTE

RFA

CE


zMeasurement circuit switch table

SymbolSwitch

ConditionMeasurementRL

OFF

ON

-

-

OFF

ON

OFF

-

ON

OFF

ON

OFF

OFF

IB

OFF

-

OFF

ON

OFF

OFF

OFF

IC

IN

PR

PF

-

IN

-

-

-

-

-

-

-

-

SW

OPEN

ICON

IP

-

IL

OPEN

OPEN

OPEN

IQ

VBIAS

VBIAS

VMOFF

VMON

VIH

VIL

IIH

IIL

VOO

VOM

ICONST

tr

tf

tr-f

LIN

IB

VOO4

VOM4

GVC

Vreg

VRL

VTHR

VRON

Ipre + Ipow

Vref

Vref

VM

VM

Vf, Vr

Vf, Vr

If, Ir

If

Vo

Vo

Icon

Moni

Moni

Vo

Vb4 / 1M

VO4

VO4

VO4, Vsin

Vreg

Vreg

Vreg

Vres

Vf = Vr = 5 [V]

Vf = Vr = 0 [V]

tr - tf

Vf = Vr = 0V

Vb = Vsin = 2.5V

IL = 100mA

IL = 0~200mA

-

-

-

-

-

-

-

-

-

-

-

-

-

-

-

-

- zOperation note

1. The BA5979S has an internal thermal shut-down circuit. If the IC chip temperature exceeds 175C (typical), the thermal shut-down circuit is enabled and mutes the output current.

2. Thermal shut-down, mute ON, and a decrease of regulator voltage will mute the driver block. The output pin voltage becomes the internal reference voltage (approximately Vcc/2).

3. Connect a by-pass capacitor (approximately 0.1F) between the bases of the power supply pins of this IC.

4. Connect pin 32 (SUB) to an external GND while connecting it to substrate inside the package. 5. The capacitor connected between the Constant Voltage Output (pin 31) and GND should have

excellent thermal characteristics, because the capacitor has the functionality for preventing oscillation. 6. If the regulator is not used, short the regulator output pin (pin 31) to Vcc and open the external

transistor base connection pin (pin 30). 7. Pin 5 is the only GND pin not connected to the substrate of IC. Exercise care when designing PC board

patterns to prevent the potential of the pin 5 from falling below the substrate GND (SUBGNS) at any time, including during transient states.


zElectrical characteristics curves


zExternal dimensions (Unit: mm)

SDIP32

4.7

0.3 0.51

Min

.

8.4

0.3

3.2

0.2

32

1 16

17

0.50.1

0.30.1

28.00.3

0 ~ 15

10.16

1.778

Documents

IC BA5979S Datasheet