1

AAT2689

PMIC Solution for 12V Adapter Systems

with 2-Output High Performance Step-Down Converters

DATA SHEET

Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

202035A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • June 8, 2012

General Description

The AAT2689 provides two independently regulated DC

outputs, consisting of a high voltage step-down (Buck)

regulator and a low input voltage low dropout (LDO) regu-

lator. The PMIC is optimized for low cost 12V adapter

inputs, making the device the ideal system-on-a-chip

power solution for consumer communications equipment.

Channel 1 is a step-down (Buck) regulator with an input

voltage range of 6V to 24V providing up to 2500mA out-

put current. 490kHz fixed switching frequency allows

small L/C filtering components. Channel 1 utilizes volt-

age mode control configured for optimum performance

across the entire output voltage and load range.

Channel 2 is a low-dropout (LDO) regulator providing up

to 600mA output current. The device provides extremely

low output noise, low quiescent current and excellent

transient response.

The controller includes integrated cycle-by-cycle over-

current protection, soft-start and over-temperature dis-

able features. Independent input and enable pins pro-

vide maximum design flexibility.

The AAT2689 is available in the Pb-free 3x4mm 16-pin

TDFN package. The rated operating temperature range is

-40°C to 85°C.

Features

• 2-Output Step-Down Converters:

• V

• I

• High Switching Frequency

• Voltage Mode Control

• PWM Fixed Frequency for Low-Ripple

• I

• 1V Dropout Voltage at 600mA

• High Accuracy ±1.5%

• Small Solution Size

• Shutdown Current <35μA

• Independent Enable Pins

• Adjustable Over-Current Protection

• Over-Temperature Protection

• Internal Soft Start

• 3x4mm 16-Pin TDFN Low Profile Thermally Enhanced

Package

• -40°C to 85°C Temperature Range

Applications

• DSL and Cable Modems

• Notebook Computers

• Satellite Settop Box

• Wireless LAN Systems

Typical Application

C10

2.2µF

C4

0.1µF

R2

2k

C7

220nF

C2 470pF

C3 56pF

R1 24.3K

R3

27.4k

R4

6.04k

D1

C9,C11

2x22µF

L1 4.7µH/5.3A

+

C1

220µF

25V

C8

330pF

R5

499

EN1

C5

2.2µF

D2

C6

2.2µF

C15

1µF

25V

1

6.0V -24.0V

3.3V/2.5A

1.8V/600mA

OS1

FB1

COMP1

OUT2

RS1

IN2

EN1

EN2

BST1

VL1

IN1

LX1

TDFN34-16

AAT2689

GND