HT95R22 -- I/O Type Phone 8-Bit MCU

General Description
The HT95R22 MCU is an 8-bit high performance, RISC architecture microcontroller device specially designed for telephone applications. Device flexibility is enhanced with its internal special features such as power-down and wake-up functions, DTMF generator, etc. These features combine to ensure applications require a minimum of external components and therefore reduce overall product costs.
Having the advantages of low-power consumption, high-performance, I/O flexibility as well as low-cost, the device has the versatility to suit a wide range of application possibilities such as deluxe feature phones, cordless phones, fax and answering machines, etc.
The device is best suited for phone products that comply with versatile dialer specification requirements for different areas or countries. The device is fully supported by the Holtek range of fully functional development and programming tools, providing a means for fast and efficient product development cycles.

Features
Operating voltage at fSYS= 3.58MHz: 2.2V~5.5V
4Kx16 OTP type Program Memory
576x8 Data Memory
18 bidirectional I/Os with pull-high options
2 NMOS output-only lines
External interrupt input
Dual 16-bit timers with interrupts
Timer external input
8-level stack
32768Hz system oscillator
32768Hz to 3.58MHz frequency-up PLL circuit
Real time clock function
Watchdog timer function
PFD driver output
DTMF generator
Power-down and wake-up feature for power-saving
operation: Idle mode, Sleep mode, Green mode and normal mode
Up to 1.117us instruction cycle with 3.58MHz system clock at VDD=2.2V~5.5V
Bit manipulation instructions
Table read function
63 powerful instructions
All instructions executed in 1 or 2 machine cycles
Supported by comprehensive suite of hardware and software tools
28-pin SOP package