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4-channel BTL driver for CD players

BA6793FP

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4-channel BTL driver for CD players
BA6793FP
The BA6793FP is a 4-channel BTL driver for CD player actuators and motors. This IC has an internal 5V regulator and a standard operational amplifier, making it suitable for a wide spectrum of applications.
FApplications CD players, CD-ROM drives
FFeatures 1) 28-pin HSOP power package allows for application miniaturization. 2) Minimum attached components. 3) Driver gain is adjustable with a single attached resistor.
4) Internal 5V regulator. (requires attached PNP transistor) 5) Internal standard operational amplifier. 6) Internal thermal shutdown circuit. 7) Three separate power supplies.
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FBlock diagram
BA6793FP
FPin descriptions
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FPin equivalent circuit diagrams
BA6793FP
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BA6793FP
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FMeasurement circuit
BA6793FP
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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. 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
BA6793FP
passed through a resistor and into the internal reference voltage component, the preamplifier output being a signal centering on the internal reference voltage. Two systems (positive phase and negative phase) are created during V / I conversion, generating BTL output via the driver buffer.
(2) Regulator This is a typical series regulator that generates a reference voltage internally. A PNP low saturation transistor must be connected.
(3) Operational amplifier A standard 4558 type.
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FApplication example
BA6793FP
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BA6793FP
FElectrical characteristic curves
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BA6793FP
FExternal dimensions (Units: mm)