Optical disc ICs
4-channel BTL driver for CD players
BA6398FP
The BA6398FP is a 4-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) 28-pin HSOP package allows for miniaturization of
applications.
2) Low number of external components.
3) Driver gain is adjustable with a single attached resis-
tor.
FAbsolute
maximum ratings (Ta = 25_C)
4) Internal 5V regulator. (requires attached PNP tran-
sistor)
5) Internal standard operational amplifier.
6) Internal thermal shutdown circuit.
FRecommended
operating conditions (Ta = 25_C)
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Optical disc ICs
FElectrical
characteristics (unless otherwise noted, Ta = 25_C, V
CC
= 8V, f = 1kHz, R
L
= 8Ω)
BA6398FP
FCircuit
operation
(1) Driver
Inputs to the IC are the focus tracking error signal from
the servo preamplifier and the control signal from the mo-
tor. 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 the internal reference
voltage component, the preamplifier output being a sig-
nal centering on the internal reference voltage. Two sys-
tems (positive phase and negative phase) are created
during V / I conversion, generating BTL output via the
driver buffer.
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