STSR3

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PIN DESCRIPTION

Pin N°

Symbol

Name and Function

1

NC

No internally connected

The supply voltage range from 4.0V to 5.5V allows applications with logic gate

threshold mosfets. UVLO feature guarantees proper start-up while it avoids

undesirable driving during eventual dropping of the supply voltage.

3

possible to choose among three different anticipation times by discrete

partitioning of the supply voltage.

4

CK

This input provides synchronization for IC’s operations, being the transitions

between the two output conditions based on a positive threshold, equal for the

two slopes. A smart internal control logic mechanism using a 15MHz internal

oscillator generates proper anticipation timing at the turn-off of each output. This

feature allows safe turn-off of Synchronous Rectifier avoiding any eventual

shoot-through situation on secondary side at both transitions. Smart clock

revelation mechanism makes these operations independent by false triggering

pulses generated in light load conditions. Absolute maximum voltage rating of the

pin can be exceeded limiting the current flowing into the pin to 10mA max.

5

INHIBIT

possible to turn off the synchronous MOSFET when the current through it tends to

reverse, allowing discontinuous conduction mode and providing protection to the

converter from eventual sinking current from the load.Absolute maximum voltage

rating of the pin can be exceeded limiting the current flowing into the pin to 10mA

max.

6

SGLGND

Reference for all the control logic signals. This pin is completely separated from

the PWRGND to prevent eventual disturbances to affect the control logic.

level.

8

PWRGND

Reference for power signals, this pin carries the full peak currents for the two

outputs.