HOLTEK
HT47C20
8-Bit R-F Type Mask MCU
 Features
Operating voltage: 2.4V~3.6V LCD bias C type
Eight bidirectional I/O lines One LCD driver with 20x3 or 19x4 segments
Four input lines One 38kHz or 40kHz IR carrier output
One interrupt input ---(455kHz or 480kHz system clock only)
One 16-bit programmable timer/event counter Two channels RC type A/D converter
---with PFD (programmable frequency divider) Four-level subroutine nesting
---function Bit manipulation instruction
Watchdog Timer 16-bit table read instruction
2Kx16 program memory ROM Up to 8.3us instruction cycle with 480kHz
64x8 data memory RAM --- system clock
One Real Time Clock (RTC) All instructions in one or two machine
One 8-bit prescaler for RTC ---cycles 63 powerful instructions
HALT function and wake-up feature reduce One buzzer output
---power consumption  
 General Description
The HT47C20 is an 8-bit high performance RISC-like microcontroller. Its single cycle instruction
and two-stage pipeline architecture make high speed applications. The device is suited for use in
multiple LCD low power applications among which are calculators, clock timers, games, scales, toys,
thermometers, hygrometers, body thermometers, capacitor scaler, other hand held LCD products,
and battery systems in particular.