Board architecture

UM1491

12/25

Doc ID 022479 Rev 1

7

Board architecture

The STEVAL-IHM021V2 can be schematized as shown in

Figure 5.

Figure 5.

STEVAL-IHM021V2 block diagram

7.1

Power supply

The power supply can address an AC input voltage ranging from 30 Vac up to 270 Vac. The

alternating current input is rectified by a diode bridge and a bulk capacitor to generate a

direct current bus voltage approximately equal to

√2 Vac (neglecting the voltage drop across

the diodes and the bus voltage ripple). A VIPer12A-E is then used in a buck converter

configuration to generate the +15-V supply voltage of the gate drivers. Finally, a linear

regulator (L78L33ABUTR) is used to generate the 3.3 V used to pull up the low-side gate

driver inputs so as to prevent the undesired turn-on of low-side switches when the J5

connector is unplugged.

Figure 6 shows a block diagram of the power supply.

Figure 6.

Power supply block diagram