DESCRIPTION

Si9113 is a current mode PWM controller for ISDN power supplies. In a 14-pin SOIC package, it provides all necessary functions to implement a single-switch PWM with a minimum of external parts. To maximize the circuit integration, the Si9113 is designed with a 200-V depletion mode MOSFET capable of powering directly off the high input bus without an external start-up circuit. The Start and Stop input voltage thresholds can be programmed within the operating input voltage range by means of a resistor divider, provided +VIN (Start) > +VIN (Stop).

FEATURES

BiC/DMOS Technology

Current Mode Control

Max 50% Duty Cycle Operation

1.3-MHz Error Amp

Up to 500-kHz Internal Oscillator

Soft-Start

0.6-V Fast Over-Current Protection

<5-µA Supply Current for +VIN <18 V

23.5-V to 200-V Input Voltage Range

Programmable Start/Stop Capability

Internal Start-Up Circuit

Power_Good Output