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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
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Optical disc ICs
FBlock diagram
BA5973FP
FPin descriptions
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Optical disc ICs
BA5973FP
FElectrical characteristics (unless otherwise noted, Ta = 25_C, VCC = 12V, PVCC = 5V, f = 1kHz, RL = 8Ω)
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Optical disc ICs
FMeasurement circuit
BA5973FP
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Optical disc ICs
FCircuit 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
BA5973FP
(3) Loading driver logic input (pins 13 and 17) truth table
(2)
Analog switch input (pin 10) truth table
FApplication example
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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.
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.
FElectrical characteristic curves
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Optical disc ICs
BA5973FP
FExternal dimensions (Units: mm)
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