BU34381 Datasheet | ROHM

Optical disc ICs Single-chip 4-bit microcontroller for CD-DA The BU34381 is a 4-bit microputer designed for CD-DA players, and has a wide array of internal I / O ponents, including an 8-bit, 8-channel AD converter, pulse width counter (PWC), two serial I / O, and an LCD controller / driver capable of displaying up to 80 segments. All LCD segments are programmable for CMOS output. These I / O ponents allow for multifunction applications with a low number of pins. FApplications Portable CD-DA players, portable CD stereos FFeatures 1) High speed operations and low voltage. (VDD = 2.7 X 5.5V at 4.4MHz) 2) Internal 8-bit, 8-channel AD converter. 3) Internal pulse width counter. 4) Two internal serial input / outputs. 5) Internal 20-segment, 4-mon LCD controller / driver. (usable with 3 mons) 6) All segments output by the LCD controller / driver are programmable for CMOS output. FAbsolute maximum ratings (Ta = 25_C) FRemended operating conditions (Ta = 25_C) Optical disc ICs FBlock diagram Optical disc ICs FPin assignments FPin descriptions Optical disc ICs Optical disc ICs FInput / output circuits Optical disc ICs FElectrical characteristics (at 5V) (unless otherwise noted, Ta = 25_C, VDD = 5V) Optical disc ICs Optical disc ICs FElectrical characteristics (at 3V) (unless otherwise noted, Ta = 25_C, VDD = 3V) Optical disc ICs FHardware descriptions (1) Operates on a single power supply (VDD = 2.7 X 5.5V) (2) Memory size 8 bits ROM : 12288 4 bits RAM : 512 LCD display RAM : 20 4 bits (3) Instruction execution time (1 cycle instruction) 1.5µsec: (at 4MHz) (4) Subroutine nesting : 8 levels (5) Interrupts : 6 factors External : 3 factors Internal (time counter, serial I / O) : 3 factors (6) ROM data table function (data table area: 12KB) (7) Two energy-saving modes (STOP / HALT) (8) Internal 20-segment LCD driver adaptable for various types of...