FExternal dimensions (Units: mm)

354

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 re-

stored when the chip temperature falls to 150

_C (typical-

ly).

(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

(5)

Be sure to connect the IC to a 0.1

µF bypass capaci-

tor to the power supply, at the base of the IC.

(6)

The radiating fin is connected to the packages inter-

nal 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.