ROHM BA5973FP

Optical disc ICs
3-channel BTL driver for CD, CD-ROM,
DVD, and DVD-ROM
BA5973FP
The BA5973FP is a 3-channel BTL driver developed for use as the actuator and loading motor driver for CD and DVD
players. Since the gain and frequency characteristics for the actuator can be set to any desired value with external components, it is can be used in a wide range of applications.
FFeatures
1) 3-channel BTL driver for CD players.
2) The HSOP-28 package allows for the design of
smaller sets.
3) Internal thermal shutdown circuit with hysteresis.
〈Actuator driver〉
4) Gain is adjustable with external resistor.
5) Contains both positive and negative input systems
for compatibility with a variety of input formats such
as reverse phase input.
〈Loading driver〉
6) Internal brake function.
7) Internal back-rush voltage protection diode.
FAbsolute maximum ratings (Ta = 25_C)
FRecommended operating conditions
701
Optical disc ICs
Block diagram
Pin descriptions
702
BA5973FP
Optical disc ICs
BA5973FP
FElectrical characteristics (unless otherwise noted, Ta = 25_C, VCC = 12V, PVCC = 5V, f = 1kHz, RL = 8Ω)
703
Optical disc ICs
Measurement circuit
704
BA5973FP
Optical disc ICs
Circuit operation
The analog switch pin 10, the mute pin 1, and the loading
driver input logic operate as shown below.
(1) Mute input (pin 1) truth table
(2)
BA5973FP
(3) Loading driver logic input (pins 13 and 17) truth
table
Analog switch input (pin 10) truth table
Application example
705
Optical disc ICs
FOperation notes
(1) The BA5973FP contains a thermal shutdown circuit.
When the chip temperature reaches 175_C (Typ.), the
output current is muted. If the chip temperature then
drops below 150_C (Typ.), then the driver circuits start
up.
FElectrical characteristic curves
706
BA5973FP
(2) Connect a bypass capacitor (approx. 0.1µF) between the bases of the power supply pins of this IC.
(3) Be sure to connect the radiation fins to an external
ground.
Optical disc ICs
BA5973FP
External dimensions (Units: mm)
707