VB525SP-E

Application schematic

Doc ID 18022 Rev 1

13/19

4

Application schematic

Figure 8.

Application diagram

4.1

Principle of operation

The VB525SP-E is mainly intended as a high voltage power switch device driven by a logic

level input and interfaces directly to a high energy electronic ignition coil.

VB525SP-E increases current in the coil to the desired, internally set current level.

After reaching this level, the coil current remains constant until the ignition point, that

phase, must have the ability to accommodate an overvoltage.

A maximum overshoot of 20 V is allowed.

4.2

Feedback

When the collector current exceeds 4.5 A, the feedback signal is turned high and it remains

so, until the input voltage is turned-off.

μP

1nF

18K

GND

FLAG

1

μF

100nF

E

LGND

+5V

BD

1K

1K

1K

Note:

ENABLE pin can be alternatively connected to LGND.