High Efficiency Dual Output

Power Supply Controller

ADP3025

Rev. A

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FEATURES

Wide input voltage range: 5.5 V to 25 V

High conversion efficiency > 96%

Integrated current sense—no external resistor required

Low shutdown current: 19 µA (typical)

Voltage mode PWM with input feed-forward for fast line

transient response

Dual synchronous buck controllers

Built-in gate drive boost circuit for driving external high-side

N-channel MOSFET

2 independently programmable output voltages:

Fixed 3.3 V or adjustable (800 mV to 6.0 V)

Fixed 5 V or adjustable (800 mV to 6.0 V)

Programmable PWM frequency

Integrated linear regulator controller

Extensive circuit protection functions

APPLICATIONS

Portable instruments

General-purpose dc-to-dc converters

GENERAL DESCRIPTION

The ADP3025 is a highly efficient, dual synchronous buck

switching regulator controller optimized for converting a

battery or adapter input into the supply voltage required in

portable products and industrial systems. The oscillator

frequency can be programmed for 200 kHz or 300 kHz

operation, or can be synchronized to an external clock signal of

up to 350 kHz.

The ADP3025 provides accurate and reliable short-circuit

protection by using an internal current sense circuit that

reduces cost and increases overall efficiency. Other protection

features include programmable soft start, UVLO, and integrated

output undervoltage/overvoltage protection. The ADP3025

contains a linear regulator controller designed to drive an

external N-channel MOSFET. The linear regulator output is

adjustable and can be used to generate auxiliary supply voltages.

The ADP3025 is specified over the 0°C to 70°C commercial

temperature range and is available in a 38-lead TSSOP package.

SIMPLIFIED FUNCTIONAL BLOCK DIAGRAM

POWER-ON

RESET

LINEAR

CONTROLLER

5.5V TO 25V

3.3V

2.5V

SS3

Q1

Q2

Q3

SS5

Q4

5V

L1

L2

PWRGD

ADP3025

REF

5V LINEAR

REGULATOR

3.3V

SWITCHING

CONTROLLER

5V

SWITCHING

CONTROLLER

800mV

PFO

3.3V

SWITCHING

CONTROLLER

Q5

Figure 1.