GENERAL DESCRIPTION
The W91550DN series are Si-gate CMOS IC tone/pulse switchable dialers containing 13 number memories and a 10-digit LCD driver for displaying telephone numbers and calling time, including a 16-digit ´ 3 one-touch memory, 16-digit ´ 10 two-touch memory dialing, and 32-digit ´ 2 redial and save memory. These dialers also provide a secrecy key, flash, two-way handfree dialing, one-key redial, hold and lock functions.

FEATURES
• Tone/pulse switchable dialer
• Two by 32-digit redial and save memory (or mercury memory)
• Three by 16-digit one-touch direct repertory memory
• Ten by 16-digit two-touch indirect repertory memory
• Memory check function
• Save/mercury function selected by pin option
• Typical interdigit pause (IDP): 800 msec (10 ppS) in pulse mode
• Uses 4 ´ 7 keyboard
• Mute key for secrecy control
• Minimum tone output duration/inter-tone pause: 87/87 mS
• Flash pause time: 1.2 sec.
• Flash break time (98, 300, 600 msec) selectable by keypad
• Pause time (2.0, 3.6, 4.0 sec.) selectable by mask option
• Pulse-to-tone (*/T) keypad for long distance call operation
• 0 or 9 dialing inhibition pin for PABX system or long distance dialing lock out
• Make/break ratio selected by pin option
• Built-in 10-digit LCD driver for telephone number display and calling time (1/3 duty, 1/2 bias)
• Built-in calling time from (00:00) to (59:59)
• On-chip power-on reset and clear LCD
• On hook debounce: 250 msec in normal mode (20 msec in lock mode)
• First key-in delay: 300 msec in lock mode
• Uses 3.579545 MHz crystal or ceramic resonator
• Packaged in 64-pin QFP