Description

The M-991 is a call progress tone generator integrated circuit for use in telephone systems. The circuit uses low-power CMOS techniques to generate tones which are digitally controlled and highly linear. The M-991 is designed to permit operation with almost any system. The use of integrated circuit techniques allows the M-991 to incorporate the control, tone generating, and power output buffer into a single 14-pin DIP or a 16-pin SOIC. A 3.58-MHz (color burst) crystal-controlled time base guarantees accuracy and repeatability.

Features

• Generates standard call progress tones

• Digital input control

• Linear (analog) output

• Power output capable of driving standard line

• 14-pin DIP and 16-pin SOIC package types

• Single supply 5V CMOS (low power)

• Inexpensive 3.58 MHz time base

• Temperature range from -25ºC to 70ºC (-01 version)

• Temperature range from -40ºC to 85ºC (-02 version)

Applications

• Telephone systems

• Test equipment

• Callback

• Security systems

• Billing systems