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5

IRUH330125AK

IRUH330125AP

Input Capacitance

Input bypass capacitors: Two (0.1

µF and 1µF) ceramics and two 100µF low ESR tantalums (AVX

TPS or equivalent), placed very close to the V

input voltage supply capacitance is more than 4 inches from the device, additional input

capacitance is recommended. Larger input capacitor values will improve ripple rejection further

improving the integrity of the output voltage.

Output Capacitance

achieved with multiple additional 1µF ceramic capacitors. Ceramic capacitors greater than 1µF in

value are not recommended as they can cause stability issues.

Tantalum capacitor values larger than the suggested value are recommended to improve the

transient response under large load current changes. The upper capacitance value limit is

10,000µF without causing the device to latch-off during start-up.

General Layout Rules

Low impedance connections between the regulator output and load are essential. Solid power and

ground planes are highly recommended. In those cases where the board impedances are not kept

very small, oscillations can occur due to the effect of parasitic series resistance and inductance

on loop bandwidth and phase margin.

The V

the connection inside the first bypass capacitor (see Fig. 2a).

Connect ceramic output capacitors directly across the V

design rules allow (see Fig. 2a). Avoid the use of vias for these capacitors and avoid loops. Fig.2

shows the ceramic capacitors tied directly to the regulator output.

Ground plane below layer 1

The input capacitors should be connected as close a possible to the V