GENERAL DESCRIPTION
This data sheet details the specific properties of the PCD3350A. The shared properties of the PCD33xxA family of microcontrollers are described in the “PCD33xxA family” data sheet, which should be read in conjunction with this publication.
The PCD3350A is a microcontroller designed primarily for telephony applications. It includes 8 kbytes ROM, 256 bytes RAM, 34 I/O lines, and an on-chip generator for dual tone multifrequency (DTMF), modem and musical tones. In addition to dialling, the generated frequencies can be made available as square waves for melody generation, providing ringer operation.

FEATURES
• 8-bit CPU, ROM, RAM, EEPROM, real-time clock and I/O; all in a 44-lead quad flat package
• 8 kbytes ROM
• 256 bytes RAM
• 256 bytes Electrically Erasable Programmable Read Only Memory (EEPROM)
• 32 kHz crystal oscillator for Real-Time Clock (RTC)
• EEPROM programmable RTC
• Over 100 instructions (based on MAB8048) all of 1 or 2 cycles
• 34 quasi-bidirectional I/O port lines
• 8-bit programmable Timer/event counter 1
• 8-bit reloadable Timer 2
• Three single-level vectored interrupts:
   – external
   – 8-bit programmable Timer/event counter 1
   – derivative; triggered by reloadable Timer 2
• Two test inputs, one of which also serves as the external interrupt input
• DTMF, modem, musical tone generator
• Reference for supply and temperature-independent tone output
• Filtering for low output distortion (CEPT compatible)
• Melody output for ringer application
• Programmable DTMF clock divider
• Power-on-reset
• Stop and Idle modes
• Supply voltage: 1.8 to 6 V (DTMF tone output and EEPROM erase/write from 2.5 V)
• CPU clock frequency: 1 to 16 MHz (3.58 MHz or 10.74 MHz for DTMF)
• Operating ambient temperature: −25 to +70 °C
• Manufactured in silicon gate CMOS process.