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5-channel BTL driver for CD players

BA6395AFP

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5-channel BTL driver for CD players
BA6395AFP
The BA6395AFP is a 5-channel BTL driver for CD player motors and actuators. This IC has an internal 5V regulator, and is suited to a wide range of applications. FApplications CD players and CD-ROM drives FFeatures 1) Internal drivers for focus coils, tracking coils, spindle motors, feed motors and loading. (The loading and spindle motor output pins are dual-use output pins and are switched between drivers using a control input.) 2) HSOP 28-pin package allows for miniaturization of applications.
3) Low number of external components. 4) Driver gain is adjustable with a single attached resistor. 5) Internal 5V regulator. (requires attached PNP transistor) 6) Internal thermal shutdown circuit.
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BA6395AFP
FBlock diagram
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FPin descriptions
BA6395AFP
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FInput / output circuits
BA6395AFP
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BA6395AFP
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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
BA6395AFP
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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BA6395AFP
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(5) Loading motor driver voltage setting Example : Forward motor
BA6395AFP
Loading driver output voltage cannot be set higher than the maximum output voltage for the power supply. The example above applies only when setting below the maximum output voltage. Maximum output volt-
age for the power supply can be output by opening the loading pin (pin 19).
FApplication example
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BA6395AFP
Optical disc ICs
BA6395AFP
FExternal dimensions (Units: mm)