AN2600 datasheet(21/30 Pages) STMICROELECTRONICS

21 / 30 page

AN2600

Test description

21/30

Figure 14.

High frequency ripple of output voltages at full load at 230 V

3.3

Measurement of RMS current of output capacitors

Table 15 shows the RMS current values flowing into the output capacitors at 230Vac, full

load. All the RMS currents are within the rating of the capacitor type indicated. This avoids

any component overstress that could affect the reliability and the expected lifetime of the

SMPS.

3.4

Dynamic load test

The dynamic load tests have been performed by varying the load on 3.3 V and 5 V outputs,

keeping the other outputs at full load. Varying the load on 3.3 V output, the following results

have been obtained:

CH1: +23 Vout (brown)

CH2: +16 Vout (blue)

CH3: +12 Vout (purple)

CH4: +5 Vout (green)

CH1: -25 Vout (brown)

CH3: +33 Vout (purple)

CH4: +3.3 Vout (green)

Table 15.

Measurement of RMS current of output capacitors at Vin= 230 V and full

load

ICapC77 (16Vout)ICapC91 (3.3Vout)ICapC81 (23Vout)ICapC102 (5Vout)

0.850

1.9

0.550

AN2600 Datasheet(PDF) 21 Page - STMicroelectronics