Date: 07/01/2009

8 bit microcontroller for telephones

The HT95R22 is an 8-bit MCU for use in telephones. The device features include 4Kx16 of program memory, 576 bytes of RAM data memory, 20 I/O pins, an 8-level stack, two 16-bit timers, RTC timer and an external interrupt function. The device is packaged in a 28-pin SOP package. Additional features are an internal Programmable Frequency Divider, PFD, which can generate a range of fixed frequencies and if used in conjunction with suitable audio generators, can generate a range of audio sounds in addition to being suitable for use in infrared carrier signal generation.

The HT95R22 also includes an internal DTMF generator function, which is suitable for use in related telecommunication products such as multi-function telephones, cordless phones, answering machines, household burglar alarms etc. Present burglar alarm products are seeing increasing widespread use and if such products use this device, they can be used to easily implement auto-dialing functions.