High Power Digital Inrush Current Controller

Reference Design

© 2015 IXYS

4

IXRD100102-1015

Service Functions

This reference design displays the capabilities of IXYS power components by featuring a Load ON/OFF

switch U2 (see Figure 8), Overload Protection functionality, and Power Good status output. Load switch

activation is programmable, and is enabled after the capacitor C pre-charge is completed. Load Switch is

activated with Power Good status signal in this reference design.

Overload Protection is an important feature to protect a device from being destroyed when an overload

occurs. The overload threshold is programmable, and is set to 12A in this reference design. If overload is

detected by a comparator, the MCU disconnects the load by turning U2 and U3 off.

Overload protection can be programmed in one of the following ways:

 Immediately shut down the device and wait for user action

 Allow the device to restart after the short circuit is removed, for a predetermined number of

short circuit occurrences.

When the device is allowed to restart, the delay between restarts and the number of restarts is

programmable. In this reference design, delay time is set to 1.5 seconds and the number of restarts is set

to 4.

Power Good status activation is programmable. In this reference design, it is delayed by one AC voltage

period after the capacitor’s pre-charge is completed. The Power Good status is not set if overload is

detected.