AP2004SL-13 - DIODES Incorporated

AP2004

PWM BUCK CONTROLLER

AP2004 Rev. 3 1 of 8 FEBRUARY 2009

www.diodes.com © Diodes Incorporated

Lead-free

• PWM B uck Control Circuitry

• Operating voltage can be up to 27V

• Under voltage Lockout (UVLO) Protection

• Short Circuit Protection (SCP)

• Soft-start circuit

• Variable Oscillator Freque ncy -- 300Khz Max

• 1.25V voltage reference Output

• 8-pin SOP package

• SOP-8L: Available in “Green” Molding Compound

(No Br, Sb)

• Lead Free Finish/ RoHS Compliant (N ote 1)

The AP2004 integrates Pulse-Width-Modulation (PWM) control

circuit into a single chip, mainly designs for power-supply

regulator. All the functions include an on-chip 1.25V reference

output, an error amplifier, an adjustable oscillator, a soft-start,

UVLO, SCP circuitry, and a push-pull output circuit. Switching

frequency is adjustable by trimming CT. During low VCC situation,

the UVLO makes sure that the outputs are off until the internal

circuit operates normally.

• Backlight inverter

• LCD Monitor

• CDROM, XDSL Product

• DC/DC converters in computers, etc.

AP 2004 S X - 13

Package PackingLead Free 13 : Tape & Reel

G : Green

S : SOP-8L L : Lead Free

Device Package

Code Packaging

(Note 2) 13” Tape and Reel

Quantity Part Number Suffix

AP2004SL-13 S SOP-8L 2500/Tape & Reel -13

AP2004SG-13 S SOP-8L 2500/Tape & Reel -13

Notes: 1. EU Directive 2002/95/EC (RoHS). All applicable RoHS exemptions applied. Please visit our website at

http://www.diodes.com/products/lead_free.html.

2. Pad layout as shown on Diodes Inc. suggested pad layout document AP02001, which can be found on our website at

http://www.diodes.com/datasheets/ap02001.pdf.

Features General Description

Applications

Ordering Information

AP2004

PWM BUCK CONTROLLER

AP2004 Rev. 3 2 of 8 FEBRUARY 2009

www.diodes.com © Diodes Incorporated

1

2

3

4

8

7

6

5

OUT

SS

COMP

SCP

VCC

GND

CT

FB

( Top View )

SOP-8L

Pin Assignments

Pin Descriptions

Pin Nam e Description

CT Timing Capacitor

FB Voltage Feedback

SS Soft-Start.

COMP Feedback Loop Compensation

OUT PWM Output

GND Ground

VCC Supply Voltage

SCP Short Circuit Protection

AP2004

PWM BUCK CONTROLLER

AP2004 Rev. 3 3 of 8 FEBRUARY 2009

www.diodes.com © Diodes Incorporated

Block Diagram

Bandgap

Reference

OUT

PWM Amplifier

FB

VCC

SCP

CT

Error Amplifier

COMP

UVLO

GND

0.7V

1.5V +

-

2.5V

Internal use

1.25V

Iss

+

-

VCC

Oscillator

MAX.300KHz

SS

+

-

Absolute Maximum Ratings

Symbol Parameter Rating Unit

PD Power dissipation at 25°C 600 mW

VCC Supply voltage 28 V

VI Ampli

f

ier input volta

g

e 20 V

VO Collector output voltage VCC-1.0V V

ISOURCE Source current 200 mA

ISINK Sink current 200 mA

TOP Operating junction temperature range -20 to +125 oC

TST Storage temperature range -65 to +150 oC

Recommended Operating Conditions

Symbol Parameter Min Max Unit

VCC Supply voltage 3.6 27 V

VI Amplifier input voltage 1.05 1.45 V

VO Collector output voltage Vcc-1.5 V

IFB Current into feedback terminal 45 µA

RF Feedback resistor 100 kΩ

CT Timing capacitor 100 6800 pF

FOSC Oscillator frequency 10 300 KHz

AP2004

PWM BUCK CONTROLLER

AP2004 Rev. 3 4 of 8 FEBRUARY 2009

www.diodes.com © Diodes Incorporated

Electrical Characteristics (TA = 25ºC, VCC = 6V, f = 200 Khz)

Reference (REF)

Symbol Parameter Conditions Min Typ. Max Unit

VREF Comp connect to FB 1.225 1.25 1.275 V

Output voltage change with

temperature TA = -20ºC ~ 25ºC -0.1 ±1 %

TA = 25ºC ~ 85ºC -0. 2 ±1 %

Under voltage lockout (UVLO)

Symbol Parameter Conditions Min Typ. Max Unit

VUT Upper threshold voltage (VCC) IO(REF) = 0.1mA

TA = 25ºC

2.9 V

VLWT Lower threshold vo ltage (VCC) 2.4 V

VHT Hysteresis (VCC) 500 mV

Short-circuit protection (SCP) control

Symbol Parameter Conditions Min Typ. Max Unit

VIT Input threshold voltage TA = 25ºC 0.60 0.67 0.75 V

VSTB Standby voltage No pull up 100 130 160 mV

VLT Latched input voltage No pull up 50 100 mV

ISCP Input (source) current VI = 0.7V, TA = 25ºC -10 -15 -20 µA

VCT Comparator threshold voltage

(COMP) 1.5 V

Oscillator (OSC)

Symbol Parameter Conditions Min Typ. Max Unit

FOSC Frequency CT = 270 pF 200 KHz

ΔFOSC Standard deviation of frequency CT = 270 pF 10 %

Frequency change with voltage VCC = 3.6V ~ 20V 1

Error-amplifier

Symbol Parameter Conditions Min Typ. Max Unit

VIO Input offset voltage VO (FB) = 1.25V ±6 mV

IIO Input offset current VO (FB) = 1.25V ±100 nA

IIB Input bias current VO (FB) = 1.25V 160 500 nA

VCM Common-mode input voltage range VCC = 3.6V ~ 20V 1.05 1. 45 V

AV Open-loop voltage amplification RF = 200 kΩ 70 80 dB

GBW Unity-gain bandwidth 1.5 MHz

CMRR Common-mode rejection ratio 60 80 dB

VOH Max. output voltage Vref-0.1 V

VOL Min. output voltage 1 V

IOI Output (sink) current (COMP) VID = -0.1V, VO = 1.25V 0.5 1.6 mA

IOO Output (source) current (COMP) VID = 0.1V, VO = 1.25V -45 -70 µA

AP2004

PWM BUCK CONTROLLER

AP2004 Rev. 3 5 of 8 FEBRUARY 2009

www.diodes.com © Diodes Incorporated

Electrical Characteristics (Continued) (TA = 25ºC, VCC = 6V, f = 200 Khz)

Output section

Symbol Parameter Conditions Min Typ. Max Unit

ILEAK Leakage current VO = 25V 10 µA

IDRV Sink current VIN = 20V 200 mA

Source current VIN = 20V 200 mA

VSAT Output saturation voltage IO = 10 mA 1.0 1.5 V

ISC Short-circuit output current VO = 6V 120 mA

PWM compar ator

Symbol Parameter Conditions Min Typ. Max Unit

VT0 Input threshold voltage at f = 10 KHz

(COMP) CT 0.6 0.7 V

VT100 Maximum duty cycle 1.2 1.3 V

Total device

Symbol Parameter Conditions Min Typ. Max Unit

ICCA Average supply current CT = 270pF 6 10 mA

Soft Start

Symbol Parameter Conditions Min Typ. Max Unit

VSS Soft-start Voltage 2.3 V

ISS Constant Charge Current 20 µA

Typical Application Circuit

L1

22uH Output

5V/5A

C2

10nF

Optional

Vcc = 12V

P mos

Q1

1

2

3

4FB

C1

470uF

R3 1K~30K

AF9435P

AF4835P

R1

OUT

VCC

COMP

GND

SCP

SS

CT

9K

5A C4

50nF

Optional

R2

C3

470uF

Step-Dow n DC /DC con vert er

8

7

6

5

C6 220nF

C5 50nF

C4 270pF 3K

Vout=Vref ⎟

⎠

⎞

⎜

⎝

⎛+2

1

1R

R

AP2004

PWM BUCK CONTROLLER

AP2004 Rev. 3 6 of 8 FEBRUARY 2009

www.diodes.com © Diodes Incorporated

Typical Characteristics

REFERENCE OUTPUT VOLTAGE

vs.

POWER-SUPPLY VOLTAGE

1.22

1.225

1.23

1.235

1.24

1.245

1.25

1.255

1.26

4 8 12 16 20 24 28

Vcc-Power Supply Voltage (V)

Vref-

Reference

Output Voltage

(V)

A

VERAGE SUPPLY CURRENT

vs.

POWER-SUPPLY VOLTA GE

0

1

2

3

4

5

0 4 8 12 16 20 24 28

Vcc - Power-Supply Voltgae (V)

Icc-Average

Supply Current

(mA)

AVERAGE SUPPLY CURRENT

vs.

AMBIENT T EMPERATURE

2

3

4

5

6

7

-50 -25 0 25 50 75 100

TA - Ambient Temperatrure(℃)

ICC - Average

Supply Current

(mA)

VCT vs. Frequency

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

0 100 200 300

Frequency (KHz)

VCT (V)

VCT(min)

VCT(max)

OSCILLATOR FREQUENCY

vs.

TIMING CAPACITANCE

0

50

100

150

200

250

300

350

100 600 1100 1600 2100 2600 3100 3600 4100 4600 5100 5600 6100 6600

CT-Timing Capacitor (pF)

fosc - Frequency

(KHz)

SCP TIME-OUT PERIOD

vs.

SCP CAPACITANCE

0

5

10

15

20

25

30

35

45 90 135 180 225 270 315 360 405 450 495

Cscp - SCP Capacitance (nF)

tscp-SCP Time-out

Period (ms)

AP2004

PWM BUCK CONTROLLER

AP2004 Rev. 3 7 of 8 FEBRUARY 2009

Typical Characteristics (Continued)

SOFT-START TIME (Ts)

vs.

SOFT-START CAPACITOR (Css)

0

5

10

15

20

25

30

25 50 75 100 125 150 175 200

Css (nF)

Ts (mS)

(1) SOP-8L

( Top View )

AP2004

YY WW

XX

Logo

Part Number

5

8

41

WW : Week : 01~52; 52

YY : Year : 08, 09,10~

G : Green

X : Internal Code

represents 52 and 53 week

L : Lead Free

Marking Information

AP2004

PWM BUCK CONTROLLER

AP2004 Rev. 3 8 of 8 FEBRUARY 2009

Package Information (All Dimensions in mm)

(1) Package Type: SOP- 8L

1.27typ 0.3/0.5

7°~9°

4.85/4.95

3.85/3.95

5.90/6.10

0.15/0.25

7°~9°

0.62/0.82

0.10/0.20

Gauge Plane

0.254

Seating Plane

0.35max. 45°

Detail "A"

1.30/1.50

1.75max.

Land Pattern Recommendation

(Unit: mm)

6x-1.27

8x-1.55

8x-0.60

5.4

0°/8°

IMPORTANT NOTICE

LIFE SU PPOR T

Diodes Incorporated and its subsidiaries reserve the right to make modifications, enhancements, improvements, corrections or other changes without further

notice to any product herein. Diodes Incorporated does not assume any liability arising out of the application or use of any product described herein; neither

does it convey any license under its patent rights, nor the rights of others. The user of products in such applications shall assume all risks of such use and will

agree to hold Diodes Incorporated and all the companies whose products are represented on our website, harmless against all damages.

Diodes Incorporated products are not authorized for use as critical components in life support devices or systems without the expressed written approval of the

President of Diodes Incorporated.