25˚C, unless otherwise noted) (Continued)

R

(Bypass FET)

Dropout Voltage vs Output Current

(Bypass Mode)

20126134

20126141

Block Diagram

20126135

Operation Description

The LM3200 is a simple, step-down DC-DC converter with a

bypass switch, optimized for powering RF power amplifiers

(PAs) in mobile phones, portable communicators, and similar

battery powered RF devices. It is designed to allow the RF

PA to operate at maximum efficiency over a wide range of

power levels from a single Li-Ion battery cell. It is based on

current-mode buck architecture, with synchronous rectifica-

tion for high efficiency. It is designed for a maximum load

capability of 300 mA in PWM mode and 500 mA in bypass

mode. Maximum load range may vary from this depending

on input voltage, output voltage and the inductor chosen.

The device has three-pin selectable operating modes re-

quired for powering RF PAs in mobile phones and other

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