UM2027
Evaluation
board objectives
DocID029048 Rev 1
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Figure 4: Inrush current at STEVAL-IHT008V1 startup on 230 V line (500 µF output DC
capacitor)
1.6
Stand-by consumption
One of the main advantages of using the T_ICL Triac in front of the rectifier bridge is that it
allows full bridge disconnection during standby to suppress losses. This can also be
achieved by adding a front-end relay (like S2 in
Figure 5: "Solution using relays to limit
inrush current and standby losses"
). But, thanks to the T_ICL Triac, this function is already
available by simply turning off this Triac.
Figure 5: Solution using relays to limit inrush current and standby losses
To give an idea of the benefits of such bridge disconnection, we measured the typical
losses of the STEVAL-IHT008V1 board in standby mode. Three cases are tested:
Case 1: STEVAL-IHT008V1 board (unmodified) with T_ICL in OFF state ("HVDC"
switch in OFF position).
Case 2: as above, but with a PTC (EPCOS B59107J0130A020) plugged in place of
the T_ICL Triac to simulate the losses for a classic solution using only one PTC and