GENERAL DESCRIPTION
The PCD3310 and PCD3310A are single-chip silicon gate CMOS integrated circuits. They are dual-standard diallers for pulse or dual tone multi-frequency (DTMF) dialling, with on-chip oscillators suitable for use with 3.58 MHz crystals.

FEATURES
• Pulse, DTMF and ‘mixed mode’ dialling
• Mixed mode dialling: start with pulse dial, end with DTMF dial (e.g. for control of DTMF user equipment via a pulse network)
• 23-digit memory stores last number dialled, or number noted during conversation (notepad)
• Redial of both PABX and external calls
• Supports 16 dial keys: 0 to 9,∗, # A, B, C, and D
• Supports 4 function keys:
– Program (P) used to input notepad numbers
– Flash (FL) allows re-dialling without on-hook
– Redial (R) recalls and redialls stored number
– Change from pulse dial to DTMF dial in mixed mode (>)
• DTMF timing:
– for manual dialling, maximum duration burst/pause intervals are user-determined, but at least minimum duration burst/pause intervals are ensured
– for redial, minimum duration burst/pause intervals are used
• On-chip voltage reference for supply and temperature independent tone output
• On-chip filtering for low output distortion (CEPT compatible)
• On-chip oscillator uses low-cost 3.58 MHz (TV colour burst) crystal or piezo resonator
• Uses standard single-contact or double-contact (common left open) keyboard
• Keyboard entries fully debounced
• Flash (register recall) output.