STSR30

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PIN DESCRIPTION

Pin N°

Symbol

Name and Function

1

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.

A blanking time of 700ns allows operation when some voltage ringing is present

during turn-off of primary switch.

Absolute maximum voltage rating of the pin can be exceeded limiting the current

flowing into the pin to 10mA max.

3

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.

4

PWRGND

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

The supply voltage range from 4.5V 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.

6

DISABLE

This pin allows turning off the device completely when kept to low level. In this

condition the IC power consumption is strongly reduced. When this pin goes to

7

SETANT

The voltage on this pin sets the anticipation in turning off the OUTGATE. It is

possible to choose among three different anticipation times by discrete

partitioning of the supply voltage [ANT].

8

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 Rectifiers avoiding any eventual

shoot-through situation on secondary side at both transitions. Clock revelation

mechanism makes the operation of STSR30 particularly suitable for flyback

adaptors application allowing correct operation during discontinuous mode.

Absolute maximum positive voltage rating of the pin can be exceeded limiting the

current flowing into the pin to 10mA max.