Introduction
Improvement of power density and reliability is a major trend for power supply manufacturers. Moving from passives and
mechanical parts to silicon devices considerably contributes to this progress.
During the startup of an AC-DC power converter, the high current due to the charge of the DC bulk capacitor can rise up to 10
times the nominal steady state current of the system. This inrush current induces a voltage drop on the AC mains that might
affect the operation of other equipment connected to the same power network.
The inrush triggers or damages the serial devices, such as the circuit breaker, the wire fuse, the capacitor, or the bridge rectifier.
To preserve the safety of the electrical installation and the reliability of the power converter, it is necessary to limit this inrush
current.
The
evaluation board introduces a simple and innovative AC-DC front-end circuit. The bridge rectifier
consists of diodes and silicon-controlled rectifiers (SCRs) that are implemented in the bridge low side.
An uninsulated power supply and a few SMD discrete components make the design very compact. The board can be easily
implemented on existing PFC or fly-back converters for plug-and-play tests. The solution, based on the high temperature
Figure 1.
STEVAL-SCR002V1 evaluation board
Getting started with the STEVAL-SCR002V1 SCR based inrush current limiter
board with non-isolated gate driver
UM2948
User manual
UM2948
-
Rev 1
-
July 2022
For further information contact your local STMicroelectronics sales office.
www.st.com
