Semiconductor Group

2

The PSB 2121 Contains the Following Functional Blocks

q

Undervoltage lockout

q

Temperature compensated voltage reference

q

Sawtooth oscillator

q

Error amplifier

q

Pulse width modulator

q

Digital current limiting

q

Soft start

q

Double pulse inhibit

q

Power driver

Together with few external components it provides a stable 5 V DC-supply for subscriber terminals

(TEs) or network terminations (NTs). It can also be programmed for higher output voltages, e.g. to

supply S-lines with 40 V.

Pin Configurations

(top view)

P-DIP-16

P-DSO-20

PSB 2121