AAT3157 Pump Datasheet

AAT3157 Datasheet, PDF, Equivalent


Part Number

AAT3157

Description

High Efficiency 1X/1.5X/2X Charge Pump

Manufacture

Skyworks

Total Page 11 Pages
Datasheet
Download AAT3157 Datasheet


AAT3157
DATA SHEET
AAT3157
High Efficiency 1X/1.5X/2X Charge Pump for White LED Applications
General Description
The AAT3157 is a low noise, constant frequency charge
pump DC/DC converter that uses a tri-mode load switch
(1X), fractional (1.5X), and doubling (2X) conversion to
maximize efficiency for white LED applications. The
AAT3157 is capable of driving up to three channels of
LEDs at 20mA per channel from a 2.7V to 5.5V input.
The current sinks may be operated individually or in par-
allel for driving higher current LEDs. A low external parts
count (two 1µF flying capacitors and two small 1µF
capacitors at IN and OUTCP) make this part ideally
suited for small, battery-powered applications.
Skyworks' S2Cwire™ (Simple Serial Control) serial digital
input is used to enable, disable, and set current for each
LED with 16 settings down to 50µA. The low-current
mode supply current can be as low as 50µA to save
power.
Each output of the AAT3157 is equipped with built-in
protection for output short-circuit and auto-disable for
load short-circuit conditions. Built-in soft-start circuitry
prevents excessive inrush current during start-up. A low-
current shutdown feature disconnects the load from the
input and reduces quiescent current to less than 1µA.
The AAT3157 is available in a Pb-free, space-saving
2.85x3.0mm 12-pin TSOPJW package.
Features
VIN Range: 2.7V to 5.5V
Fully Programmable Current with Single Wire
16 Current Levels
Four Low Current Settings Down to 50µA
Low IQ (50µA) for Low Current Mode
Tri-Mode 1X, 1.5X, and 2X Charge Pump for Maximum
Efficiency and VF Coverage
Drives up to Three Channels of LEDs
No Inductors, Low Noise Operation
1MHz Constant Switching Frequency
Small Application Circuit
Built-In Thermal Protection
Automatic Soft Start
IQ <1µA in Shutdown
2.85x3.0mm TSOPJW-12 Package
Applications
Color (RGB) Lighting
Programmable Current Sinks
White LED Backlighting
White Photo Flash for Digital Still Cameras
Typical Application
C1
1µF
2.7V to 5.5V
CIN
1µF
EN/SET
C1+ C2+
C1- C2-
IN OUTCP
AAT3157
GND
EN/SET
D1
D2
D3
C2
1µF
D1 D2 D3
COUT
1µF
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
202152A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 11, 2012
1

AAT3157
DATA SHEET
AAT3157
High Efficiency 1X/1.5X/2X Charge Pump for White LED Applications
Pin Descriptions
Pin #
1
2
3
4
5
6
7
8
9
10
11
12
Symbol
D3
D2
D1
GND
IN
C2-
C2+
OUTCP
C1-
C1+
EN/SET
N/C
Function
Current sink input #3.
Current sink input #2.
Current sink input #1.
Ground.
Input power supply. Requires 1µF capacitor connected between this pin and ground.
Flying capacitor 2 negative terminal.
Flying capacitor 2 positive terminal. Connect a 1µF capacitor between C2+ and C2-.
Charge pump output to drive load circuit. Requires 1µF capacitor connected between this pin and ground.
Flying capacitor 1 negative terminal.
Flying capacitor 1 positive terminal. Connect a 1µF capacitor between C1+ and C1-.
S2Cwire serial interface control pin.
No connection.
Pin Configuration
TSOPJW-12
(Top View)
D3
D2
D1
GND
IN
C2-
1
2
3
4
5
6
12 N/C
11 EN/SET
10 C1+
9 C1-
8 OUTCP
7 C2+
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com
2 202152A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 11, 2012


Features DATA SHEET AAT3157 High Efficiency 1X/1. 5X/2X Charge Pump for White LED Applica tions General Description The AAT3157 is a low noise, constant frequency char ge pump DC/DC converter that uses a tri -mode load switch (1X), fractional (1.5 X), and doubling (2X) conversion to max imize efficiency for white LED applicat ions. The AAT3157 is capable of driving up to three channels of LEDs at 20mA p er channel from a 2.7V to 5.5V input. T he current sinks may be operated indivi dually or in parallel for driving highe r current LEDs. A low external parts co unt (two 1µF flying capacitors and two small 1µF capacitors at IN and OUTCP) make this part ideally suited for smal l, battery-powered applications. Skywor ks' S2Cwire™ (Simple Serial Control) serial digital input is used to enable, disable, and set current for each LED with 16 settings down to 50µA. The low -current mode supply current can be as low as 50µA to save power. Each output of the AAT3157 is equipped with built-in protection for output.
Keywords AAT3157, datasheet, pdf, Skyworks, High, Efficiency, 1X/1.5X/2X, Charge, Pump, AT3157, T3157, 3157, AAT315, AAT31, AAT3, Equivalent, stock, pinout, distributor, price, schematic, inventory, databook, Electronic, Components, Parameters, parts, cross reference, chip, Semiconductor, circuit, Electric, manual, substitute




@ 2014 :: Datasheetspdf.com :: Semiconductors datasheet search & download site (Privacy Policy & Contact)