L7590C

Stresses in excess of the absolute maximum ratings can cause permanent damage to the device. These are absolute stress ratings only. Functional operation of the device is not implied at these or any other conditions in excess of those given in the operational sections of this data sheet. Exposure to absolute maximum ratings for extended periods may adversely affect device reliability.

The L7590C Telephone Ringing Driver produces a low-frequency sinusoidal ringing signal for analog telephone loops. L7590Cis accomplished by producing an output pulse stream that is an amplified replica of the digital input. The output is then filtered to produce a sine wave. The peak-to-peak output level is determined by the magnitude of the negative high-voltage dc applied to the device (up to 170 V).

The required input is a 100 kHz CMOS-compatible pulse stream, pulse-width modulated (PWM) at the desired ringing frequency. The output stage consists of one upper and one lower drive transistor with an internal control circuit.

The L7590C IC is optimized for low power dissipation and is available in a 16-pin, surface-mount package.