ZXSC100

SEMICO NDUC TORS

ISSUE 3 - JANUARY 2004

16

Output voltage ripple

Output voltage ripple is shown in Figure 8. The circuit

is operated with a 1.2V input voltage, 3.3V output

voltage and 100mA load current. Output voltage ripple

will be dependent, to a large extent, on the output

capacitor ESR. (see Applications section for

recommended capacitors).

Figure 8. Output voltage ripple for 3.3V/100mA

output.

Transient response

Transient response to step changes in load is a critical

feature in many converter circuits. The ZXSC100

operates a pulse by pulse regulation scheme and

therefore corrects for changes in the output every

pulse cycle, giving excellent response characteristic.

Measurement with a power supply

When measuring with a power supply it is important

to realise that the impedance is much greater than that

of a secondary battery (NiCd or NiMH). To simulate the

lower impedance of the battery x10 low ESR 1000uF

capacitors where placed in parallel at the input of the

converter.

All

the

dynamic

performance

measurements were taken using this technique.