General Description
The HT46R51A/HT46R52A are 8-bit high performance, RISC architecture microcontroller devices specifically designed for A/D applications that interface directly to analog signals, such as those from sensors. The advantages of low power consumption, I/O flexibility, timer functions, oscillator options, multi-channel A/D converter, Pulse Width Modulation function, HALT and wake-up functions, watchdog timer, as well as low cost, enhance the versatility of these devices to suit a wide range of A/D application possibilities such as sensor signal processing, chargers, motor driving, industrial control, consumer products, subsystem controllers, etc.

Features
Low-power fully static CMOS design
Operating voltage:
   fSYS=4MHz: 2.2V~5.5V
   fSYS=8MHz: 3.3V~5.5V
Program Memory:
   1Kx15 OTP (HT46R51A)
   2Kx15 OTP (HT46R52A)
Data memory:
   96x8 RAM (HT46R51A)
   128x8 RAM (HT46R52A)
A/D converter: 12bitsx5Ch External A/D converter reference voltage input pin
14 bidirectional I/O lines
1 interrupt input shared with an I/O line
8-bit programmable timer/event counter with overflow interrupt and 8-stage prescaler
On-chip crystal and RC oscillator
6-level subroutine nesting
Watchdog Timer
Low voltage reset function
HALT function
Up to 0.5µs instruction cycle with 8MHz system clock at VDD=5V
1-channel 8-bit PWM output shared with an I/O line
PFD function
Bit manipulation instruction
Table read instruction
63 powerful instructions
All instructions in one or two machine cycles
16-pin NSOP, 18-pin DIP, 20-pin SOP/SSOP package