UM0984

Measurements

Doc ID 17812 Rev 2

17/25

4.2

Standby

Figure 8.

Standby power vs. input voltage

The standby behavior of the board is displayed in Figure 8. The blue line is the standby input

power of the fully assembled board. The red line is the standby input power of the board

without linear regulator L78L33 and with a 15 V Zener diode applied as a bleeder. The

typical input current of L78L33 is 3.5 mA which is approximately 40 mW of load present on

the secondary side.

The standby input power was directly measured by power analyzer NORMA 4000. The

output connection was kept open during the measurement.