Optical disc ICs
FThermal
derating curve
BA6790FP/BA6791FP
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
remain at the internal bias voltage, roughly (V
CC
/ 2).
(5) Be sure to connect the IC to a 0.1µF 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.
FExternal
dimensions (Units: mm)
354
ROHM [ ROHM ]
