Diodes AP3154A User Manual

AP3154A

120mA HIGH EFFICIENCY WHITE LED DRIVER

Features

• Up to 88% Max power efficiency

• Wide input voltage range: 2.7V ~ 5.5V

• 1x, 1.5x, and 2x charge-pump modes

• Drive up to 4 white LEDs

• Default maximum current setting: 20mA each channel

• 120mA maximum output current through 4 channels

• Programmable switching frequency, default 1.2MHz

• Spread Spectrum Control with 10% frequency deviatio n

• 1-wire Serial Digital Interface (SDI) or PWM for dimming

control

• Soft-start during power-up and mode switching

• Soft-stop during s hutdown

• Short-circuit protection

• Over-voltage protection and under-voltage lockout

• Low shutdown curr ent < 6

• Industry-leading low profile package

• Lead Free package: DFN3030-12

• DFN3030-12: Available in “Green” Molding Compound

(No Br, Sb)

• Lead Free Finish / RoHS Compliant (Note 1)

µA

Applications

• Mobile Phone

• PDA (Personal Digital Assistant)

• White LED Backlighting

• Camera Flash LED Lighting

• LCD Modules

• Portable Devices

General Description

The AP3154A is a high efficiency charge-pump white LED driver with 1x, 1.5x, 2x operating modes. The AP3154A operates on power supplies from 2.7v to 5.5v. It drives up to four channels of white LEDs while the intensity of each channel is configured by varying the respective current levels. Each channel can supply up to 30mA current. Up to four channels can be ganged together to provide maximum load current of 120mA. By default, all 4 channels are set to the minimum current level after the chip is enabled or back from shutdown mode.

The Serial Digital Interface (SDI) provides the capability to configure the current for each LED channel. Some other key features, such as Up Spread Spectrum Control, different charge-pump switching frequencies (0.6MHz/1.2MHz/1.8MHz), and PWM dimming control, can also be programmed through the interface.

The AP3154A has a built-in soft-start circuit to minimize the inrush current during power-up and mode switching. Various protections such as short-circuit, over-voltage, under-voltage, and thermal shutdown are integrated to ensure system reliability. The quiescent current of AP3154A during shutdown is less than 6

µA.

Typical Application Circuit

8

V

IN

V

IN

1uF

C

IN

AP3154A

2

SDI

GND

9

AP3154A Rev. 1 1 of 14 AUGUST 2009

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V

C2

C2 C1

C1

OUT

D4 D3 D2 D1

6

P

N

P

N

1uF

C

7

2

3

1uF

C

4

1

5

D4

LED

D3

LED

D2

LED

D1

LED

1uF

C

OUT

1 12 11 10

Ordering Information

AP3154A

120mA HIGH EFFICIENCY WHITE LED DRIVER

AP 3154 A F G - 7

Package

F : DFN3030-12

Green

G : Green

Packing

7 : Tape & Reel

Device

Package

Code

Packaging

(Note 2)

Quantity Part Number Suffix

7” Tape and Reel

AP3154AFG-7 F DFN3030-12 3000/Tape & Reel -7

Notes: 1. EU Directi ve 2 002/95/EC (RoHS). All applicable RoHS exemptions applied. Please visit our website at

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

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

Pin Assignment

( Top View )

V

D4

C1

OUT

C2

1

2

3

P

4

N

5

P

Exposed

Pad

12

D3

11

D2SDI

10

D1

9

GND

8

V

IN

76

C2

N

DFN3030-12

AP3154A Rev. 1 2 of 14 AUGUST 2009

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AP3154A

120mA HIGH EFFICIENCY WHITE LED DRIVER

Pin Descriptions

Pin Name Pin # Description

D4 1 Current Sink Input #4. Connect to V SDI 2 1-wire Serial Digital Interface Input / PWM input

C1P 3 Positive Terminal of Flying Capacitor. Connect a 1µF capacitor between C1P and C1N. C1N 4 Negative Terminal of Flying Capacitor.

V

OUT

5

The charge pump output voltage to drive load circuit. Connect a 1µF capacitor

between this pin and ground.

C2P 6 Positive Terminal of Flying Capacitor. Connect a 1µF capa citor between C2P and C2N. C2N 7 Negative Terminal of Flying Capacitor.

VIN 8 Input Power Source. Connect a 1µF capacitor between this pin and ground.

GND 9 Ground.

D1 10 Current Sink Input #1. Connect to V D2 11 Current Sink Input #2. Connect to V D3 12 Current Sink Input #3. Connect to V

GND

EP PAD

Exposed Pad (bottom). Connect to groun d u n d e r n ea th t he package.

when un-used.

OUT

when un-used.

OUT

when un-used.

OUT

when un-used.

OUT

Block Diagram

V

IN

SDI

C2

P

SERIAL

DIGITAL

INTERFACE

BANDGAP

OSCILLATOR

OVER

TEMPERATURE

PROTECTION

UNDER

VOLTAGE

LOCKOUT

C1

C2

N

CHARGE PUMP

SWITCHES

C1

P

DIGITAL

CONTROL

BLOCK

CURRENT CONTROL

N

V

OUT

SHORT

CIRCUIT

PROTECTION

OUTPUT VOLTAGE REGULATION LED SHORT CIRCUIT DETECTION

&

GND

OVER

VOLTAGE

PROTECTION

D1

D2

D3

D4

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AP3154A

120mA HIGH EFFICIENCY WHITE LED DRIVER

Absolute Maximum Ratings (Notes 3)

Symbol Description Value Units

ESD HBM Human Body Model ESD Protection

ESD MM Machine Model ESD Protection 200 V

V

IN

VSDI SDI to GND Voltage -0.3 to VIN + 0.3 V

I

OUT

PD Maximum Power Dissipation 0.85 W

TJ Operating Junction Temperature Range -40 to 150 °C

Notes: 3. Exceeding Absolute Maximum Ratings will cause permanent damage to the device.

Input Voltage -0.3 to 6 V

Maximum DC Output Current 150 mA

2

Recommended Operating Conditions

Symbol Parameter Min Max Units

VIN

TA

Input Voltage 2.7 5.5 V Operating Ambient Temperature

-40 85 °C

KV

AP3154A Rev. 1 4 of 14 AUGUST 2009

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AP3154A

120mA HIGH EFFICIENCY WHITE LED DRIVER

Electrical Characteristics

= C

C

IN

Symbol Description Conditions Min Typ. Max Units

I

V

Notes: 4. Determined by the average current levels of all active channels.

= C1 = C2 = 1.0µF; TA = 25°C, VIN = 3.5V. Unless otherwise stated.

OUT

1X Mode

IQ Quiescent Current

Fosc=1.2MHz,

1.2 mA

SDI=HIGH, no load

I

Shutd own Current SDI = 0 0.3 6 µA

SHDN

I

Current Accuracy

IDX

D-Match

SINK

(Note 4) Current Matching (Note 5)

= 20mA -10 10 %

I

SINK

V

: D1=D2=D3=D4

F

I

= 2, 20mA

D

5 %

TSS Soft-start Time 1 ms

F

Switching Clock Frequency 0.6/1.2/1.8 MHz

CLK

F

Spread Spectrum Enabled +10 %

SSP

SDI Threshold Low VIN = 2.7V to 5.5V 0.4 V

SDI(L)

SDI Threshold High VIN = 2.7V to 5.5V 1.6 V

SDI(H)

T

SDI Low Time 0.05 50 µs

SLO

T

SDI High Time 0.05 50 µs

SHI

f

T

I

PWM

PLO

OFF

SEP

I

SDI

SCP

θ

PWM Frequency (Range 1) 0.2 1.5 KHz PWM Frequency (Range 2) 20 30 KHz

PWM Signal Period

PWM Signal Lo w (LED off) 1 T

PWM Signal High (LED on) 1 T

PHI

Chip Disable (held low)

Interval betw ee n S D I sequences (held high)

PWM 65 100 ms No PWM 512 800 µs PWM 65 100 ms No PWM 512 800 µs

f

PWM

1/

-Max

1/ f

-Min µs

PWM

– 1 µs

PWM

– 1 µs

PWM

SDI Input Leakage -1 1 µA

Short to GND hold

V

OUT

Current Thermal Resistance1 –

JA

Junction to Ambient Maximum Thermal Resistance1 –

JC

Junction to Case

5. Defined as the deviation of any sink current from the average of all active current channels.

6. Device mounted on FR-4 substrate PC board, 2oz copper, with minimum recommended pad layout.

500 mA DFN3030-12

(Note 6) DFN3030-12

(Note 6)

160 °C/W

21 °C/W

AP3154A Rev. 1 5 of 14 AUGUST 2009