GENERAL DESCRIPTION

The W91820N is a series of tone/pulse switchable telephone dialers with 13 memory, keytone, hold, lock, and handfree dialing control features. These chips are fabricated using Winbonds high-performance CMOS technology and thus offer good performance in low-voltage, low-power operations.

FEATURES

• Tone/pulse switchable dialer

• Two by 32 digits redial and save memory

• Three by 32 digits one-touch direct repertory memory

• Ten by 32 digits two-touch indirect repertory memory

• Pulse-to-tone (*/T) keypad for long distance call operation

• Chain dialing

• Uses 5 x 5 keyboard

• Easy operation with redial, flash, pause, and */T keypads

• Pause, P->T (pulse-to-tone) can be stored as a digit in memory

• Dialing rate:10 ppS or 20 ppS by mask option

• Minimum tone output duration: 93 mS (unless W91824N/AN is 87 mS)

• Minimum intertone pause: 93 mS (unless W91824N/AN is 87mS)

• Pause time: 3.6 sec. (unless W91824N/AN is 2.0 sec.)

• Flash break time (73 mS, 100 mS, 300 mS, or 600 mS) selectable by keypad; pause time is 1.0 S

• Make/break ratio (2:3 or 1:2) selectable by MODE pin

• Mute key for speech network mute

• No key will be accepted except the HOLD key when in the Hold mode

• Key tone output for valid keypad entry recognition

• On-chip power-on reset

• Uses 3.579545 MHz crystal or ceramic resonator

• 20, or 22-pin dual-in-line plastic package