GENERAL DESCRIPTION
The W91540N series are tone/pulse switchable telephone dialers with 10 memories, keytone or lock function, and handfree dialing control. These chips are fabricated using Winbonds high-performance CMOS technology and thus offer good performance in low-voltage and low-power operations.

FEATURES
• DTMF/pulse switchable dialer
• Two by 32-digit redial and save memory
• Ten by 16 digit two-touch indirect repertory memory
• Pulse-to-tone (*/T) keypad for long distance call operation
• Cascaded 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
• 0 or 9 dialing inhibition pin for PABX system or long distance dialing lock out
• Dialing rate (10 ppS or 20 ppS) selected by bonding option
• Minimum tone output duration: 93 mS (W91544AN: 87 mS)
• Minimum intertone pause: 93 mS (W91544AN: 87 mS)
• Pause time: 3.6 sec
• 300 mS off-hook delay in lock mode (DP remains low for 300 mS while off-hook)
• 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
• Key tone output for valid keypad entry recognition
• On-chip power-on reset
• Uses 3.579545 MHz crystal or ceramic resonator
• Packaged in 18 or 20-pin DIP