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Date: 9/13/04

SP6123 Low Voltage, Synchronous Step Down PWM Controller

© Copyright 2004 Sipex Corporation

A more detailed description of the waveform is shown below.

Internal SSTART

pops to ~ internal

SSTART voltage +0.7V

Internal SSTART rises until

to attempt RESTART

COMP Clamps

~ 3V

After pop, COMP

retains internal

SSTART slope

ENABLE

Part

Attempt

RESTART

5µA PULLUP slope to 0.3V;

35µA PULLUP to 0.7V

Overcurrent Detected

(Fault Mode Enabled)

COMP

SP6123 OVER CURRENT (HICCUP MODE)

Test Conditions

V

V

BST = 5.0V

SWN - tied to GND through 1k Resistor

COMP – released from GND

OPERATION