AN4382 datasheet(21/70 Pages) STMICROELECTRONICS

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AN4382

ZVS LC resonant stage description

of the peak is therefore dependent on the propagation delay (~200 ns) generated by the

driver and the MOSFET gate capacitance. An internal fixed STLUX385A delay shall be also

considered (< 50 ns).

Given that the propagation time depends from the final board construction, the use shall

measure the final propagation time and use the “dt” command to program the application

specific propagation time.

4.1.4

Transformer output voltage

Transformer XF can be realized using a center tapped secondary side winding or a single

ended secondary side. The structure of this component and the relevant rectifiers are

shown in Figure 10.

Figure 10. ZVS output circuits

The transformer used in the STEVAL385LEDPSR demonstration board is configured as

center tapped.

In order to change the output from the default 100 V (max 1 A) to 200 (max 0.5 A), the user

shall perform the following steps:

•

Mount the D42 and D43 with the 2 x STTH3R06S (SMC package)

•

Remove the R102.

Note:

The STTH3R06S component are not included in the STEVAL385LEDPSR demonstration

board.

AN4382 Datasheet(PDF) 21 Page - STMicroelectronics