Datasheet BA6791FP, BA6790FP Datasheet (ROHM)

Optical disc ICs

4-channel BTL driver for CD players

BA6790FP / BA6791FP

The BA6790FP and BA6791FP are 4-channel BTL drivers for CD player actuators and motors. These ICs have internal
5 V regulators and general purpose operational amplifiers, and are mounted to a 28-pin HSOP package, allowing for
the miniaturization of applications.

Applications
CD players and portable CD

Features

1) 4-channel BTL driver.

2) HSOP 28-pin package allows for miniaturization of
applications.

3) Wide dynamic range. (typically 5.4V when V
and RL = 8Ω)

CC = 8V

4) Internal thermal shutdown circuit.

5) Gain is adjustable with a single attached resistor.

6) Internal 5V regulator. (requires attached PNP tran­sistor)

7) Internal general purpose operational amplifier.

Block diagram

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Optical disc ICs BA6790FP/BA6791FP

FPin descriptions

FAbsolute maximum ratings (Ta = 25_C)

FRecommended operating conditions

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Optical disc ICs BA6790FP/BA6791FP

FElectrical characteristics (unless otherwise noted, Ta = 25_C, VCC = 8V, f = 1kHz, RL = 8Ω)

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Optical disc ICs BA6790FP/BA6791FP

Measurement circuit

351

Optical disc ICs BA6790FP/BA6791FP

Measurement circuit switch table

Input/output circuits

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Optical disc ICs BA6790FP/BA6791FP

Application example

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Optical disc ICs BA6790FP/BA6791FP

FThermal derating curve FOperation notes

(1) The BA6790FP and BA6791FP have an internal
thermal shutdown circuit. Output current is muted when
the chip temperature exceeds 175_C (typically) and re­stored when the chip temperature falls to 150_C (typical­ly).
(2) If the mute pin (pin 7) voltage is opened or lowered
below 0.5V , the output current will be muted. Pin 7 should
be pulled up above 2.0V during normal use.
(3) The bias pin (pin 23) is muted when lowered below

1.4V (typically). Make sure it stays above 1.6V during

normal use.
(4) Muting occurs during thermal shutdown, mute-on
operations or a drop in the bias pin voltage. In each case,
only the drivers are muted. During muting, the output pins
remain at the internal bias voltage, roughly (V
(5) Be sure to connect the IC to a 0.1µF bypass capaci­tor to the power supply, at the base of the IC.
(6) The radiating fin is connected to the packages inter­nal GND, but should also be connected to an external
ground.
(7) The capacitor between regulator output (pin 6) and
GND also serves to prevent oscillation of the IC, so select
one with good temperature characteristics.

CC/2).

FExternal dimensions (Units: mm)

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