Optical disc ICs
FElectrical characteristics (unless otherwise noted, Ta = 25_C, VCC = 8V, f = 1kHz, RL = 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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