June 2016

DocID029452 Rev 1

1/6

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STEVAL-ISF003V1

Low standby losses power front-end with inrush current-limitation

Data brief

Features



Fully electronic solution without the need for

an inrush current limiter resistor and its bulky

bypass electromechanical relay



DC bus disconnection at standby to reduce

losses below 0.3 W



Inrush current compliance with IEC61000-3-

3



Operation allowed with PFC (continuous or

discontinuous)



Compliant with EN 55015, IEC 61000-4-11



Criteria A at 4 kV IEC 61000-4-5 and at 4 kV

IEC 61000-4-4



RoHS compliant

Description

The STEVAL-ISF003V1 evaluation board allows

limitation of the inrush current charging a DC bus

capacitor, to comply with standard IEC 61000-3-

3. This inrush current limitation is based on a

soft-start procedure of the mixed bridge diodes

and SCRs rectifier using progressive phase

control at board start-up.

This solution drastically reduces standby losses

as the DC bus can be totally disconnected from

the AC mains when it does not have to operate.

DC bus deactivation is simply achieved by

turning off SCRs, without requiring an additional

relay to open the circuit in standby.

The steady-state losses are also reduced, thanks

to the removal of the NTC / PTC resistor

traditionally used to limit the inrush current, which

in turn removes the need for a relay to bypass it.