Advanced Monolithic Systems, Inc.

www.advanced-monolithic.com

Phone (925) 443-0722 Fax (925) 443-0723

Advanced

AMS4122

Monolithic

SINGLE 4A/DUAL 2A BUCK CONVERTER IN SO8

Systems

RoHS compliant

FEATURES

APPLICATIONS

• 2 Independent Asynchronous Buck Converters in SO-8

• Audio Power Amplifiers

• Internally compensated

• Portable (Notebook) Computers

• Built in soft start

• Point of regulation for high performance electronics

• Enable with Zero current shut down

• Consumer Electronics

• 400KHz switching per output

• Desktop Computers

• Interleaved oscillator to reduced supply ripple

• LCD TVs and LCD monitors

• Simply re-configures to 2 phase single output

• Distributed Power Systems

• Up to 4A output in 2 phase mode

• Battery Chargers

• Independent hiccup current limit

• Pre-Regulator for Linear Regulators

GENERAL DESCRIPTION

AMS4122 is a dual switching regulator capable to deliver up to 2A for each channel. Internally Compensated internal Soft Start

makes AMS4122 one of the simplest and easiest switching regulators to use with the minimum external components. Each

regulator has independent hiccup current limit. The Enable pin turns both devices on when a voltage of 2.5V or higher it is

applied to EN pin. Since both devices share one single package the thermal protection turns off both devices when the die

temperature exceeds approximately 135°C. Both regulators are adjustable using a 0.600V reference for low output voltage

settings. The oscillators are 180° phase to each other to reduce the ripples on the input power supply and minimize the power

dissipation on the package. The device can be easily configured for Two Phase single output switching regulator capable of 5A

output load. By applying a 2.5V or greater on feedback pin of the second switching regulator the device enters in Two Phase

Mode. The first benefit of having a Two Phase device is reducing the output ripples by a factor of four as the single phase. The

second benefit is higher output current capability at overall low cost. AMS4122 combined with AMS4123 (2A Switching

Regulator + 1A LDO in SO-8) makes complete solution for LCD TV power requirements.

ORDERING INFORMATION

PINCONNECTIONS

TYPICAL APPLICATION

Package Type

SOIC EDP

TEMP. RANGE

AMS4122S

-25°C to 125°C

8L SOIC

SO Package (S)

2

8

3

4

7

6

5

EN

F/ B 1

F/ B 2

P1+AVIN

P2VIN

GND

1

SW 1

SW 2

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