AiT A7525E6R-ADJ Schematic [ru]

AiT Semiconductor Inc.

www.ait-ic.com

A7525

500mA, 1.2MHz HIGH EFFICIENCY

SYNCHRONOUS STEP-UP DC-DC CONVERTER

DESCRIPTION

FEATURES

The A7525 is synchronous, fixed frequency,

step-up DC/DC converters delivering high

efficiency in a 6-lead SOT package. Capable of

supplying 3.3V at 100mA from a single AA cell

input, the device contain an internal NMOS switch

and PMOS synchronous rectifier. A switching

frequency of 1.2MHz minimizes solution footprint

by allowing the use of tiny, low profile inductors

and ceramic capacitors. The current mode PWM

design is internally compensated, reducing

external parts count.

The A7525 features continuous switching at light

loads. Anti-ringing control circuitry reduces EMI

concerns by damping the inductor in discontinuous

mode, and the device features low shutdown

current of under 1uA.

The A7525 is available in SOT-26 package.

 High Efficiency: Up to 92%
 1.2MHz Constant Switching Frequency
 3.3V Output Voltage at I

OUT

=100mA from a Single

AA Cell; 5.0V Output Voltage at I

OUT

=500mA from

one Li battery.

 Low Start-up Voltage: 1.0V
 Integrated main switch and synchronous rectifier.
 No Schottky Diode Required
 2.5V to 5V Output Voltage Range
 Automatic Pulse Skipping Mode Operation
 Tiny External Components
 <1μA Shutdown Current
 Anti-ringing Control Reduces EMI
 Available in SOT-26 Package

APPLICATION

 Cellular and Smart Phones
 Microprocessors and DSP Core Supplies
 Wireless and DSL Modems
 MP3 Player
 Digital Still and Video Cameras
 Portable Instruments

TYPICAL APPLICATION CIRCUIT

ORDERING INFORMATION

Package Type

Part Number

SOT-26

E6

A7525E6R-ADJ

A7525E6VR-ADJ

Note

V: Halogen free Package
R : Tape & Reel

AiT provides all RoHS products
Suffix “ V “ means Halogen free Package

REV1.0 - JAN 2012 RELEASE - - 1 -

AiT Semiconductor Inc.

www.ait-ic.com

A7525

500mA, 1.2MHz HIGH EFFICIENCY

SYNCHRONOUS STEP-UP DC-DC CONVERTER

PIN DESCRIPTION

Top View

Pin #

Symbol

Function

1

CE

Chip Shutdown Signal Input. Logic high is normal operation mode, Logic Low is Shutdown

2,3

GND

Ground 4 LX

Power Switch Pin. It is the switch node connection to Inductor

5

VDD

Power Output Pin

6

FB

Feedback Input Pin. Connect FB to the center point of the external resistor divider.

The feedback threshold voltage is 1.23V

REV1.0 - JAN 2012 RELEASE - - 2 -

AiT Semiconductor Inc.

www.ait-ic.com

A7525

500mA, 1.2MHz HIGH EFFICIENCY

SYNCHRONOUS STEP-UP DC-DC CONVERTER

ABSOLUTE MAXIMUM RATINGS

Input Voltage

-0.3V～+6V

FB, CE Voltage

-0.3V～+6V

VDD Voltage

-0.3V～+6V

Operating Temperature, T

OPR

NOTE1

-40℃～＋85℃

Storage Temperature Range

-65℃～＋150℃

Lead Temperature (Soldering, 10sec)

＋300℃

Package

θJA

θJC

SOT-26

250℃/W

110℃/W

Stresses above may cause permanent damage to the device. These are stress ratings only and functional operation of the device at
these or any other conditions beyond those indicated in the Electrical Characteristics are not implied. Exposure to absolute maximum
rating conditions for extended periods may affect device reliability.
NOTE1: TJ is calculated from the ambient temperature TA and power dissipation PD according to the following formula:

TJ = TA + (PD) x (250°C/W)

THERMAL RESISTANCE

REV1.0 - JAN 2012 RELEASE - - 3 -

AiT Semiconductor Inc.

www.ait-ic.com

A7525

500mA, 1.2MHz HIGH EFFICIENCY

SYNCHRONOUS STEP-UP DC-DC CONVERTER

ELECTRICAL CHARACTERISTICS

Parameter

Condition

Min.

Typ.

Max.

Unit

Minimum Start-Up Voltage

I

OUT

=1mA

- 1 -

V

Minimum Operating Voltage

VCE = VIN

－

0.8 - V

Output Voltage Range

2.5 - 5

V

Feedback Voltage

-40 ℃≤TA≤ 85℃

1.192

1.230

1.268

V

Quiescent Current(Shutdown)

V

SHDN

= 0V

0.01 1 μA

Quiescent Current(Active)

Measured on V

OUT

300

500

μA

NMOS Switch Leakage

VSW = 5V

-

0.1 5 μA

PMOS Switch Leakage

VSW = 0V

-

0.1 5 μA

NMOS Switch ON Resistance
V

OUT

= 3.3V

0.40 - Ω

V

OUT

= 5V

-

0.35 - Ω

PMOS Switch ON Resistance
V

OUT

= 3.3V

-

0.70 - Ω

V

OUT

= 5V

-

0.60 - Ω

Output Voltage

V

OUT

= 3.3V, I

OUT

= 1mA

3.201

3.300

3.399

V

V

OUT

= 5V , I

OUT

= 1mA,

VIN = 2.4V

4.850

5.000

5.150

V

Line Regulation

V

IN

= 0.8V to 3.0V,

I

OUT

= 10mA

- 1 -

%/V

Load Regulation

I

OUT

= 1mA to 100mA

-

0.02

-

%/mA

NMOS Current Limit

600

850 - mA

Current Limit Delay to Output

Note 2

-

40 - ns

Max Duty Cycle

VFB = 1.15V,

-40℃ ≤TA≤ 85℃

80

85 - %

Switching Frequency

0.95

1.2

1.5

MHz

-40℃ ≤TA ≤85℃

0.85

1.2

1.5

MHz

CE Input Threshold

0.35

0.60

1.50

V

CE Input Current

VCE = 5.5V

0.01 1 μA

VIN =1.2V, V

=3.3V, TA=25°C, unless otherwise specified

OUT

NOTE2: Guaranteed by design

REV1.0 - JAN 2012 RELEASE - - 4 -

AiT Semiconductor Inc.

www.ait-ic.com

A7525

500mA, 1.2MHz HIGH EFFICIENCY

SYNCHRONOUS STEP-UP DC-DC CONVERTER

TYPICAL PERFORMANCE CHARACTERISTICS

1. Efficiency vs. Output Current

V

OUT

=3.3V, TA = 25°C

2. Input current vs. Output current

V

OUT

=5.0V, TA = 25°C

3. Output Voltage vs. Output Current

V

OUT

=3.3V, TA = 25°C

4. Output Voltage vs. Output Current

V

OUT

=5.0V, TA = 25°C

5. Minimum Start-Up Voltage vs. Output Current

V

OUT

=3.3V, TA = 25°C

6. Maximum Output Current vs. Input Voltage

L=4.7uH, TA = 25°C

REV1.0 - JAN 2012 RELEASE - - 5 -