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Optical disc ICs BA5937AFP
(2) Voltage setting for loading motor driver (ex: forward mode)
∗When setting the output voltage from the loading driver,
even if an output voltage is set that exceeds the maxi-
mum output voltage with respect to the power supply
voltage, the output will not exceed the maximum output
voltage.
If a voltage is set that is under the maximum output volt-
age, the example above is applicable. Also, by having the
loading input (pin 19) open, the maximum output voltage
with respect to the power supply voltage is output.
(3) The BA5937AFP contains a thermal shutdown cir-
cuit.
When the chip temperature reaches 175C (Typ.), the
output current is muted. If the chip temperature then
drops below 150C (Typ.), then the mute is released.
(4) If the voltage of the bias pin (pin 23) drops below
1.0V (Typ.), outputs are muted.
For normal conditions, have the voltage above 1.4V and
below 6.5V.
(5) By having the mute pin (pin 7) voltage pulled up to
2.0V or greater, you can mute the output current for chan-
nels 1 and 4. For normal conditions, have pin 7 open or
at 0.5V or below.
(6) If the voltage of the thermal shutdown, mute ON, or
bias pin drops, the mute is activated; however, in these
situations, only the drivers are muted. Also, the output pin
voltage becomes the internal bias voltage (approx.
(V
CC*VF)/2).
(7) Connect a bypass capacitor (approx. 0.1µF) be-
tween the bases of the power supply pins of this IC.
(8) Even though the radiation fins are connected to
ground within the package, be sure to also connect them
to a ground externally as well.
