Optical disc ICs
4-channel BTL driver for CD players
BA6897S / BA6897FP
The BA6897S and BA6897FP are a 4-channel BTL dr...
Optical disc ICs
4-channel BTL driver for CD players
BA6897S / BA6897FP
The BA6897S and BA6897FP are a 4-channel BTL driver for CD player motors and actuators. It has an internal 5V
regulator and standard operational amplifier, and is suited to a wide range of applications. FApplications CD players, CD-ROM drives FFeatures 1) Minimal number of external components. 2) Driver gain is adjustable with just one attached resistor. 3) Internal 5V
regulator (attached
PNP transistor necessary).
4) Internal standard operational amplifier. 5) Internal thermal shutdown circuit.
FAbsolute maximum ratings (Ta = 25_C)
FRecommended operating conditions (Ta = 25_C)
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Optical disc ICs
FBlock diagram
BA6897S/BA6897FP
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Optical disc ICs
FPin descriptions BA6897S
BA6897S/BA6897FP
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Optical disc ICs
BA6897FP
BA6897S/BA6897FP
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Optical disc ICs
FInput / output circuits
BA6897S/BA6897FP
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Optical disc ICs
BA6897S/BA6897FP
FElectrical characteristics (unless otherwise noted, Ta = 25_C, VCC = 8V, f = 1kHz, RL = 8Ω)
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Optical disc ICs
FMeasruement circuit (BA6897S)
BA6897S/BA6897FP
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Optical disc ICs
FCircuit operation (1) Driver Inputs to the IC are the focus tracking error signal from the servo preamplifier and the control signal from the motor.
BA6897S/BA6897FP
The input signals, which normally center on 2.5V, are V / I converted by the preamplifier, generating a current corresponding to the input voltage. This current is passed through a resistor and into th...