Diodes AP3202 User Manual

380kHz, 2A Asynchronous DC-DC Buck Converter AP3202

Preliminary Datasheet

General Description

The AP3202 is a 380kHz fixed frequency, current
mode, PWM buck (step-down) DC-DC converter,
capable of driving a 2A load with high efficiency,
excellent line and load regulation. The device
integrates N-channel power MOSFET switch with
low on-resistance. Current mode control provides fast
transient response and cycle-by-cycle current limit.

A standard series of inductors are available from
several different manufacturers optimized for use
with the AP3202. This feature greatly simplifies the
design of switch-mode power supplies.

This IC is available in SOIC-8 package.

Features

• Input Voltage Range: 4.75V to 18V

• Fixed 380kHz Frequency

• High Efficiency: up to 93%

• Output Current: 2A

• Current Mode Control

• Built-in Over Current Protection

• Built-in Thermal Shutdown Function

• Built-in UVLO Function

• Built-in Over Voltage Protection

• Built-in Soft-start

Applications

• LCD TV

• Set Top Box

• Portable DVD

• Digital Photo Frame

Figure 1. Package Type of AP3202

SOIC-8

Mar. 2011 Rev. 1. 2 BCD Semiconductor Manufacturing Limited

1

Preliminary Datasheet

380kHz, 2A Asynchronous DC-DC Buck Converter AP3202

Pin Configuration

M Package
(SOIC-8)

Figure 2. Pin Configuration of AP3202 (Top View)

Pin Description

Pin Number Pin Name Function

Bootstrap pin. A bootstrap capacitor is connected between the BS pin

1

2

3

4

5

6

7

8

BS

IN

SW

GND Ground pin

FB

COMP

EN

NC No Connection

and SW pin. The voltage across the bootstrap capacitor drives the
internal high-side power MOSFET
Supply input pin. A capacitor should be connected between the IN pin
and GND pin to keep the input voltage constant
Power switch output pin. This pin is connected to the inductor and
bootstrap capacitor

Feedback pin. This pin is connected to an external resistor divider to
program the system output voltage. When the FB pin voltage exceeds
20% of the nominal regulation value of 1.222V, the over voltage
protection is triggered. When the FB pin voltage is below 0.6V, the
oscillator frequency is lowered to realize short circuit protection
Compensation pin. This pin is the output of the transconductance
error amplifier and the input to the current comparator. It is used to
compensate the control loop. Connect a series RC network from this
pin to GND. In some cases, an additional capacitor from this pin to
GND pin is required
Control input pin. Forcing this pin above 1.5V or set this pin floating
enables the IC. Forcing this pin below 0.5V shuts down the IC. When
the IC is in shutdown mode, all functions are disabled to decrease the
supply current below 1µA

Mar. 2011 Rev. 1. 2 BCD Semiconductor Manufacturing Limited

2

Preliminary Datasheet

380kHz, 2A Asynchronous DC-DC Buck Converter AP3202

Functional Block Diagram

2

IN

Current

Sense

Amplifier

S

R

PWM

Comparator

1.8V

8

NC

EN

INTERNAL

PULL
HIGH

7

0.5/1.5V

Short

Protection

Comparator

Internal Bias

And Regulator

Oscillator

90k/380k

Shutdown

Comparator

0.6

5

FB

1.222

CLK

Error

Amplifier

SLOP

COMP

6

COMP

Figure 3. Functional Block Diagram of AP3202

Ordering Information

AP3202 -

Circuit Type

Package

Package

M: SOIC-8

Temperature

Range

Part Number Marking ID Packing Type

5V

1

BS

M1

Q

Q

0.22

M2
10

3

SW

4

GND

G1: Green

TR: Tape & Reel
Blank: Tube

SOIC-8

-40 to 85°C

AP3202M-G1 3202M-G1 Tube

AP3202MTR-G1 3202M-G1 Tape & Reel

BCD Semiconductor's Pb-free products, as designated with "G1" suffix in the part number, are RoHS compliant
and green.

Mar. 2011 Rev. 1. 2 BCD Semiconductor Manufacturing Limited

3

Preliminary Datasheet

380kHz, 2A Asynchronous DC-DC Buck Converter AP3202

Absolute Maximum Ratings (Note 1)

Parameter Symbol Value Unit

IN Pin Voltage VIN -0.3 to 20 V

EN Pin Voltage VEN -0.3 to VIN V

SW Pin Voltage VSW 20 V

BS Pin Voltage VBS -0.3 to VSW+6 V

FB Pin Voltage VFB -0.3 to 6 V

COMP Pin Voltage V

Thermal Resistance

Operating Junction Temperature TJ 150 ºC

Storage Temperature T

Lead Temperature (Soldering, 10sec) T

ESD (Machine Model) 200 V

ESD (Human Body Model) 2000 V

-0.3 to 6 V

COMP

θJA

-65 to 150 ºC

STG

260 ºC

LEAD

105 ºC/W

Note 1: Stresses greater than those listed under “Absolute Maximum Ratings” 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 under “Recommended Operating Conditions” is not implied. Exposure to “Absolute
Maximum Ratings” for extended periods may affect device reliability.

Recommended Operating Conditions

Parameter Symbol Min Max Unit

Input Voltage VIN 4.75 18 V

Maximum Output Current I

Operating Ambient Temperature TA -40 85 ºC

OUT(Max)

2 A

Mar. 2011 Rev. 1. 2 BCD Semiconductor Manufacturing Limited

4

Preliminary Datasheet

380kHz, 2A Asynchronous DC-DC Buck Converter AP3202

Electrical Characteristics

VIN=VEN=12V, V

o

=25

T

C, and those in boldface type apply over the full operating temperature range (T

A

Parameter Symbol Conditions Min Typ Max Unit

Input Voltage VIN 4.75 18 V

Quiescent Current IQ VFB=1.4V, VEN=2V 1.0 1.5 mA

=3.3V, unless otherwise specified. Specification with standard typeface are for

OUT

=-40oC to 85oC)

A

Shutdown Supply Current I

Feedback Voltage VFB

Feedback Over Voltage
Threshold

Feedback SCP Voltage Threshold V

Feedback Bias Current IFB VFB=1V -0.1 0.1

High-side Switch On-resistance (Note 2) R

Low-side Switch On-resistance (Note 2) R

High-side Switch Leakage Current I

High-side Switch Current Limit I

Low-side Switch Current Limit I

EN Pin Threshold

EN Pull-up Current I

Input UVLO Threshold V

Input UVLO Hysteresis V

Oscillator Frequency F

Short Circuit Oscillator
Frequency

Maximum Duty Cycle D

Minimum Duty Cycle D

VEN=0V 1 10

SHDN

1.185 1.222 1.258

1.48 V

V

FBOV

FBSCP

0.6 V

µA

V

µA

ISW=0.5A

DSONH

ISW=0.05A

DSONL

=18V, VEN=0V

V

IN

LEAKH

2.8 3.8 A

LIMH

From drain to source 0.15 A

LIML

V

1.5

ENH

V

0.5

ENL

VEN=0V 1.0

EN-PH

VIN Rising 3.5 3.9 4.4 V

UVLO

0.3 V

HYS

380 kHz

OSC1

90 kHz

F

OSC2

VFB=1.0V 90 %

MAX

VFB=1.5V 0 %

MIN

=0V

V

SW

0.1 10

0.22

10

Ω

Ω

µA

V

µA

Error Amplifier Voltage Gain (Note 3) AEA 400 V/V

Error Amplifier Transconductance GEA 700

COMP to Current Sense
Transconductance

Thermal Shutdown (Note 3) T

Thermal Shutdown Hysteresis (Note 3) T

Soft-start Time (Note 3) tSS I

V-V

Note 2: R

DSON

=

SW2SW1

SW2SW1

I-I

2.4 A/V

G

CS

160 ºC

OTSD

30 ºC

HYS

=0A 500

OUT

µA/V

µs

Note 3: Not tested, guaranteed by design.

Mar. 2011 Rev. 1. 2 BCD Semiconductor Manufacturing Limited

5

Preliminary Datasheet

380kHz, 2A Asynchronous DC-DC Buck Converter AP3202

Typical Performance Characteristics

o

TA=25

C, V

=12V, V

IN

=3.3V, unless otherwise noted.

OUT

100

90
80

70
60
50
40

Efficiency (%)

30
20
10

0

0.00.20.40.60.81.01.21.41.61.82.0

Output Current (A)

VIN=5V
VIN=12V

375
350
325
300
275

250
225

200
175
150

High-side Switch On-resistance (mΩ)

125

-40 -20 0 20 40 60 80 100 120 140

Case Temperature (oC)

Figure 4. Efficiency vs. Output Current Figure 5. R

vs. Case Temperature

DSONH

20

18

16

14

12

10

8

Low-side Switch On-resistance (Ω)

6

4

-40 -20 0 20 40 60 80 100 120 140

Case Temperature (oC)

1.30

1.25

1.20

1.15

1.10

Feedback Voltage (V)

1.05

1.00

-60 -40 -20 0 20 40 60 80 100 120 140

Case Temperature (oC)

Figure 6. R

vs. Case Temperature Figure 7. Feedback Voltage vs. Case Temperature

DSONL

Mar. 2011 Rev. 1. 2 BCD Semiconductor Manufacturing Limited

6

Preliminary Datasheet

380kHz, 2A Asynchronous DC-DC Buck Converter AP3202

Typical Performance Characteristics (Continued)

o

T

=25

C, V

A

=12V, V

IN

=3.3V, unless otherwise noted.

OUT

1.5

1.4

1.3

1.2

1.1

1.0

0.9

0.8

Quiescent Current (mA)

0.7

0.6

0.5

-60 -40 -20 0 20 40 60 80 100 120 140

Case Temperature (oC)

Figure 8. Quiescent Current vs. Figure 9. Output Voltage vs.

Case Temperature Output Current

3.50

3.45

3.40

3.35

3.30

3.25

3.20

Output Voltage (V)

3.15

3.10

3.05

3.00

0.0 0.5 1.0 1.5 2.0

Output Current (A)

V

V

EN

2V/div

V

OUT

1V/div

IL

1A/div

VSW

10V/div

Figure 10. Enable Turn on Characteristic Figure 11. Enable Turn off Characteristic

(I

Time (10ms/div)

=2A, CC Mode) (I

OUT

EN

2V/div

V

OUT

1V/div

I

1A/div

V

SW

10V/div

L

Time (10ms/div)

=2A, CC Mode)

OUT

Mar. 2011 Rev. 1. 2 BCD Semiconductor Manufacturing Limited

7

Preliminary Datasheet

380kHz, 2A Asynchronous DC-DC Buck Converter AP3202

Typical Performance Characteristics (Continued)

o

T

=25

C, V

A

=12V, V

IN

=3.3V, unless otherwise noted.

OUT

V

V

OUT

2V/div

I

L

1A/div

VEN

2V/div

V

SW

5V/div

Figure 12. Enable Turn on Characteristic Figure 13. Enable Turn off Characteristic

Time (800µs/div)

(I

=2A, Resistance Load) (I

OUT

OUT

2V/div

1A/div

V

2V/div

V

SW

5V/div

I

L

EN

Time (400µs/div)

=2A, Resistance Load)

OU T

V

OUT

2V/div

V

OUT

2V/div

1A/div

I

L

1A/div

I

L

V

V

SW

5V/div

SW

5V/div

Time (100µs/div)

Time (100µs/div)

Figure 14. Short Circuit Protection Figure 15. Short Circuit Recovery

=2A) (I

(I

OUT

OUT

=2A)

Mar. 2011 Rev. 1. 2 BCD Semiconductor Manufacturing Limited

8

Preliminary Datasheet

380kHz, 2A Asynchronous DC-DC Buck Converter AP3202

Typical Application

Figure 16. Typical Application of AP3202

Mar. 2011 Rev. 1. 2 BCD Semiconductor Manufacturing Limited

9

Preliminary Datasheet

380kHz, 2A Asynchronous DC-DC Buck Converter AP3202

Mechanical Dimensions

SOIC-8 Unit: mm(inch)

4.700(0.185)

5.100(0.201)

7

°

7

°

1.270(0.050)
TYP

0.100(0.004)

0.300(0.012)

1.350(0.053)

1.750(0.069)

0.675(0.027)

0.725(0.029)

D

2

D

1

:

0

0.320(0.013)

5.800(0.228)

6.200(0.244)

0.800(0.031)

°

8

°

8

0.200(0.008)

0

°

8

°

1°
5°

0.450(0.017)

0.800(0.031)

)

6

0

0

.

0

(

0

5

1

.

0

R

1.000(0.039)

0.330(0.013)

0.510(0.020)

R0.150(0.006)

3.800(0.150)

4.000(0.157)

0.190(0.007)

0.250(0.010)

0.900(0.035)

Note: Eject hole, oriented hole and mold mark is optional.

Mar. 2011 Rev. 1. 2 BCD Semiconductor Manufacturing Limited

10

BCD Semiconductor Manufacturing Limited

IMPORTANT NOTICE

IMPORTANT NOTICE

BCD Semiconductor Manufacturing Limited reserves the right to make changes without further notice to any products or specifi-

BCD Semiconductor Manufacturing Limited reserves the right to make changes without further notice to any products or specifi-

cations herein. BCD Semiconductor Manufacturing Limited does not assume any responsibility for use of any its products for any

cations herein. BCD Semiconductor Manufacturing Limited does not assume any responsibility for use of any its products for any

particular purpose, nor does BCD Semiconductor Manufacturing Limited assume any liability arising out of the application or use

particular purpose, nor does BCD Semiconductor Manufacturing Limited assume any liability arising out of the application or use

of any its products or circuits. BCD Semiconductor Manufacturing Limited does not convey any license under its patent rights or

of any its products or circuits. BCD Semiconductor Manufacturing Limited does not convey any license under its patent rights or

other rights nor the rights of others.

other rights nor the rights of others.

http://www.bcdsemi.com

MAIN SITE

MAIN SITE

- Headquarters

BCD Semiconductor Manufacturing Limited

BCD Semiconductor Manufactur ing Limited

- Wafer Fab

No. 1600, Zi Xing Road, Shanghai ZiZhu Science-based Industrial Park, 200241, China

Shanghai SIM-BCD Semiconductor Manufacturing Limited

Tel: [phone], Fax: [phone]

800, Yi Shan Road, Shanghai 200233, China
Tel: [phone], Fax: [phone]

REGIONAL SALES OFFICE

Shenzhen Office

REGIONAL SALES OFFICE

Shanghai SIM-BCD Semiconductor Manufacturing Co., Ltd., Shenzhen Office

Shenzhen Office

Unit A Room 1203, Skyworth Bldg., Gaoxin Ave.1.S., Nanshan District, Shenzhen,

Shanghai SIM-BCD Semiconductor Manufacturing Co., Ltd. Shenzhen Office

China

Advanced Analog Circuits (Shanghai) Corporation Shenzhen Office

Tel: [phone]

Room E, 5F, Noble Center, No.1006, 3rd Fuzhong Road, Futian District, Shenzhen 518026, China

Fax: [phone]

Tel: [phone]
Fax: [phone]

- Wafer Fab

BCD Semiconductor Manufacturing Limited

Shanghai SIM-BCD Semiconductor Manufacturing Co., Ltd.

- IC Design Group

800 Yi Shan Road, Shanghai 200233, China

Advanced Analog Circuits (Shanghai) Corporation

Tel: [phone], Fax: [phone]

8F, Zone B, 900, Yi Shan Road, Shanghai 200233, China
Tel: [phone], Fax: [phone]

Taiwan Office
BCD Semiconductor (Taiwan) Company Limited

Taiwan Office

4F, 298-1, Rui Guang Road, Nei-Hu District, Taipei,

BCD Semiconductor (Taiwan) Company Limited

Tai wan

4F, 298-1, Rui Guang Road, Nei-Hu District, Taipei,

Tel: [phone]

Taiwan

Fax: [phone]

Tel: [phone]
Fax: [phone]

USA Office
BCD Semiconductor Corp.

USA Office

30920 Huntwood Ave. Hayward,

BCD Semiconductor Corporation

CA 94544, USA

30920 Huntwood Ave. Hayward,

Tel : [phone]

CA 94544, U.S.A

Fax: [phone]

Tel : [phone]
Fax: [phone]