FEATURES: AY-5-9151A
.
2.5V to 5V and 200μA operation, plus standby mode
Frequency of on-chip clock set by external RC network
Selectable break: make ratio and interdigital pause
Uses 3 x 4 matrix keyboard with no keyboard ground or
common contact
Keyboard inputs have antibounce protection
Input pull-up or pull-down resistors on-chip
Redial and access pause controlled from keyboard
22 digit capacity including access pauses
Dialer reset for line power breaks>200ms.
FEATURES: AY-5-9151B. Same as AY-5-9151A except:
18 Pin package
FEATURES: AY-5-9152. Same as AY-5-9151A except:
■ Break: Make fixed at 60:40 plus:
■ Two antiphase mask outputs for driving bistable relay
FEATURES: AY-5-9152/B. Same as AY-5-9152 except:
■18 Pin package
FEATURES: AY-5-9153A. Same as AY-5-9151A when in 3 x 4
matrix keyboard mode plus:
Π Pin selectable options of 1 of 12 keyboard, 2 of 7 keyboard
wired to produce 4-bit code with common
■8 bit output for displaying number in digit store
■Simple call-barring facility using display outputs
FEATURES: AY-5-9153B. Same as AY-5-9153A except:
■Keyboard is binary input with common
FEATURES: AY-5-9154A. Same as AY-5-9153A except:
Break: Make fixed at 60:40 plus:
Two antiphase mask outputs for driving bistable relay

DESCRIPTION
This range of CMOS Pushbutton Dialers consists of seven devices
AY-5-9151A to AY-5-9154A, all of which perform the function of
converting input data (e.g. from a keyboard) into a series of
pulses suitable for loop disconnect dialing. The series is based
on two devices: a simple, basic dialer circuit and a more complex
and versatile device which accepts a variety of data entry codes
and has a display facility.
The use of CMOS technology results in low voltage and current
requirements, enabling easy interfacing with a variety of
telephones. The versatility of the devices and the low external
component count enables the building of sophisticated, reliable
telephones at low cost.