CS5161, CS5161H

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10

Figure 8. CS5161/5161H Peak−to−Peak Ripple on

M 1.00 μs

Trace 1− Regulator Output Voltage (10 mV/div.)

Trace 2− Inductor Switching Node (5.0 V/div.)

Transient Response

time provides unprecedented transient response to changes

in input voltage or output current. Pulse by pulse adjustment

of duty cycle is provided to quickly ramp the inductor

current to the required level. Since the inductor current

cannot be changed instantaneously, regulation is maintained

by the output capacitor(s) during the time required to slew

the inductor current.

For best transient response, a combination of a number of

high frequency and bulk output capacitors are usually used.

If the maximum on time is exceeded while responding to

a sudden increase in load current, a normal off time occurs

to prevent saturation of the output inductor.

Output Voltage Response to a 12 A Load Pulse.

100 μs/div.

Trace 2− Regulator Output Voltage (output set for 1.55 V, 20 mV/div.)

Output Voltage Response to a 0 to 12 A Load Increase

10 μs/div.

Trace 2− Regulator Output Voltage (output set for 1.55 V, 20 mV/div.)

Trace 1− Inductor Switching Node (5.0 V/div.)

Voltage Response to a 12 to 0 A Load Decrease

10 μs/div.

Trace 2− Regulator Output Voltage (output set for 1.55 V, 20 mV/div.)

Trace 1− Inductor Switching Node (5 V/div.)

PROTECTION AND MONITORING FEATURES

To maintain predictable startup and shutdown

prevent the part from operating below 8.70 V minimum

and guarantees a 8.55 V minimum shutdown threshold.

Short Circuit Protection

A lossless hiccup mode short circuit protection feature is

provided, requiring only the Soft Start capacitor to

implement. If a short circuit condition occurs