Optical disc ICs
FApplication example
BA6798S
FOperation notes
(1) The BA6798S has an internal thermal shutdown cir-
cuit. Output current is muted when the chip temperature
exceeds 175_C (typically).
(2) If the mute pin (pin 6) voltage is opened or lowered
below 0.5V, the output current will be muted. Pin 6 should
be pulled up above 2.0V during normal use.
(3) The bias pin (pin 17) 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 or supply volt-
age. In each case, only the drivers are muted. During
muting, the output pins remain at the internal bias volt-
age, roughly (VCC*VF / 2).
(5) The driver circuit shuts down when the supply volt-
age drops below 4.5V (typically), and starts up again
when the voltage rises above 4.7V (typically).
(6) Be sure to connect the IC to a 0.1µF bypass capaci-
tor to the power supply, at the base of the IC.
(7) The capacitor between regulator output (pin 7) and
GND also serves to prevent oscillation of the IC, so select
one with good temperature characteristics.
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