569

Optical disc ICs

Single-chip 4-bit microcontroller for
CD-DA

BU34675

The BU34675 is a compact 4-bit, single-chip microcontroller that includes all the I / O required for CD system control.
Circuits on the chip include a pulse width measurement counter (PWC), SIO, and an LCD controller / driver for a 28-seg-
ment display. The LCD segments can all be switched in software to CMOS output, and the extensive I / O allows many
functions with a low pin count.

Applications

Portable CD-DA, CD / radio / cassette players

Features

1) Low-voltage, high-speed operation (V

= 2.3 to 5.5V

at 4.4MHz).

2) Pulse width measurement counter on chip (for re-

mote control reception).

3) SIO provided for communication with the DSP.

4) Seven-segment, four-common LCD controller / driv-

er on chip.

5) All segments of the LCD controller / driver output can