Diodes AP3608E User Manual

Data Sheet

EIGHT-CHANNEL CONSTANT CURRENT SINK WITH CURRENT MATCH AP3608E

General Description

The AP3608E is an eight-channel constant current sink
with current match used for LED driver. It uses an
external resistor to set the current for eight LED strings
with an accuracy of ±1.5%. The full scale LED current
can be adjusted from 10mA to 100mA for each chan­nel. The LED light can be adjusted by PWM dimming
function.

The device can keep working when LED opens with­out damage. It features under voltage lockout protec­tion and over temperature protection.

The AP3608E has four interface terminals (FB, SDB,
FBX and SDBX pins). The first two terminals allow
the device to work with a DC/DC converter to drive
LED arrays for good performance. And the other two
enable the device to be connected in parallel.

The AP3608E is available in QFN-4
20(EDP) and SOIC-20 packages.

×4-24, TSSOP-

Features

· Input Voltage Range: 4.2V to 5.5V

· Typical Output Current: 480mA (60mA/1V per

Channel)

· Maximum Output Current: 800mA (100mA/1.5V

per Channel)

· Current Match Accuracy: ±1.5%

· PWM Dimming Control

· Open LED Self-check and Protection

· Under Voltage Lockout Protection

· Over Temperature Protection

· FBX and SDBX Pins Enable Parallel Application

Applications

· Notebook

· LCD Display Modules

· LCD Monitor

· LCD TV

QFN-4×4-24 TSSOP-20(EDP) SOIC-20

Figure 1. Package Types of AP3608E

Mar. 2011 Rev. 1. 5 BCD Semiconductor Manufacturing Limited

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Data Sheet

EIGHT-CHANNEL CONSTANT CURRENT SINK WITH CURRENT MATCH AP3608E

Pin Configuration

FN Package

(QFN-4×4-24)

Pin 1 Dot by Marking

CH2 CH3 CH4 CH5 CH6

1

CH1

2

NC

3

NC

NC

PWM

NC

4

5

6

NC

Exposed

Pad

78 9101112

ISET FB SDB

G/M Package

(TSSOP-20(EDP)/SOIC-20)

CH1

1

CH2

2

CH3

3

CH4

4

PGND

1920212224 23

18

CH7

17

CH8

16

EN

15

VCC

AGND

14

NC

13

SDBXFBX

EN

20

VCC

19

AGND

18

SDBX

17

PGND

PGND

Note: AGND must be quiet and directly connected to total C

CH5

CH6

CH7

CH8

5

6

7

8

9

10

16

15

14

13

12

11

SDB

FB

ISET

FBX

NC

PWM

IN

Figure 2. Pin Configuration of AP3608E (Top View)

Mar. 2011 Rev. 1. 5 BCD Semiconductor Manufacturing Limited

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Data Sheet

EIGHT-CHANNEL CONSTANT CURRENT SINK WITH CURRENT MATCH AP3608E

Pin Description

Pin Number

QFN-4

1, 24, 23, 22,

20, 19, 18, 17

2 ,3 ,4, 6, 7, 13 12 NC No connection

511PWM

813FBX

914ISET

10 15 FB

11 16 SDB

12 17 SDBX

14 18 AGND

TSSOP-20(EDP)/

×4-24

SOIC-20

1, 2, 3, 4, 7, 8, 9, 10 CH1to CH8 White LED cathode connection pin. These pins should be connected to

Pin Name Function

GND if not used

PWM dimming control pin. Adding a PWM signal to this pin to control
LED dimming (see Figure 10 for detail dimming control mode). If not
used, connect it to the high level

This pin is an interface terminal. Connecting it with FB pin can achieve
parallel application. If not used, leave it unconnected

LED current set pin. An external resistor is connected to this pin to set
each channel current according to I

Feedback pin. This pin is an interface terminal, which samples the volt­age of each channel, and outputs the lowest voltage of the string to DC/
DC converter

This pin is an interface terminal. SDB pin outputs low logic to DC/DC
converter under the conditions such as AP3608E receives shutdown sig­nal from EN pin or all channels are inactive. When AP3608E is on
PWM dimming mode, the signal in SDB pin is synchoronous with PWM
signal

This pin is an interface terminal. Connecting it with SDB pin can
achieve parallel application. If not used, connect it to GND

Ground pin. It would be useful when connected with PGND and
exposed pad

CHANNEL

=1.194*400/R

ISET

15 19 VCC Input voltage pin

16 20 EN Enable pin. Logic high enables the IC and logic low disables the IC

21 5, 6 PGND

EP

Ground pin. It would be useful when connected with AGND and
exposed pad

Exposed pad. It would be useful when connected with AGND and
PGND

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Data Sheet

EIGHT-CHANNEL CONSTANT CURRENT SINK WITH CURRENT MATCH AP3608E

Functional Block Diagram

EN

SDB

SDBX

ISET

PWM

16

(20)

11

(16)

12

(17)

9 (14)

5 (11)

VCC

EN

Logic

Disable

or

All STG

or

Synchronous

with PWM

Signal

V

REF

PWM Dimming

Bandgap

OPA

+

100mV

100mV

4

CH1...CH8

Test

DFF

V

CC

OTP

8

EN

GND

14, 21 (5, 6, 18)15 (19)

EN

UVLO

V

REF

Time

Out

STG

(Short To GND)

3V

COMP

Max.(CH1...CH8)

Min.(CH1...CH8,FBx)

CH3CH4CH5CH6CH7CH8

8

100:1

EN

V

CC

1

6

8

CH1...CH8

8 (13)

(15)

CH2

CH1

1 (1)

FBX

10

FB

CH1

Current Sink

24
(2)

Current Sink

Current Sink

Current Sink

Current Sink

Current Sink

Current Sink

Current Sink

23
(3)

22
(4)

20
(7)

19
(8)

18
(9)

17

(10)

CH2

CH3

CH4

CH5

CH6

CH7

CH8

A (B)
A for QFN-4

×4-24

B for TSSOP-20(EDP)/SOIC-20

Figure 3. Functional Block Diagram of AP3608E

Mar. 2011 Rev. 1. 5 BCD Semiconductor Manufacturing Limited

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Data Sheet

EIGHT-CHANNEL CONSTANT CURRENT SINK WITH CURRENT MATCH AP3608E

Ordering Information

AP3608E -

Circuit Type

Package

FN: QFN-4

×4-24

G1: Green

TR: Tape and Reel
Blank: Tube

G: TSSOP-20(EDP)
M: SOIC-20

Package Temperature Range Part Number Marking ID Packing Type

QFN-4×4-24

TSSOP-20(EDP) AP3608EGTR-G1 AP3608EG-G1 Tape & Reel

SOIC-20

-40 to 85

o

C

AP3608EFNTR-G1 B3B Tape & Reel

AP3608EM-G1 AP3608EM-G1 Tube

AP3608EMTR-G1 AP3608EM-G1 Tape & Reel

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

Absolute Maximum Ratings (Note 1)

Parameter Symbol Value Unit

Input Voltage V

ISET Pin Voltage V

EN Pin Voltage V

Feedback Pin Voltage V

SDB Pin Voltage V

PWM Pin Voltage V

Voltage per Channel (Note 3) V

CC

ISET

EN

FB

SDB

PWM

CHX

QFN-4×4-24 60
Thermal Resistance
(Junction to Ambient, No Heat Sink)

θ

JA

TSSOP-20(EDP) 35 (Note 2)

SOIC-20 87

Operating Junction Temperature T

Storage Temperature Range T

Lead Temperature (Soldering, 10sec) T

J

STG

LEAD

ESD (Machine Model) 200 V

ESD (Human Body Model) 6000 V

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.

Note 2: The chip is soldered to 60mm2 (4mm×15mm) copper (top side solder mask) of 1oz. on PCB with 8×0.5mm vias.
Note 3: Breakdown voltage.

-0.3 to 6 V

-0.3 to 6 V

-0.3 to 6 V

-0.3 to 6 V

-0.3 to 6 V

-0.3 to 6 V

-0.3 to 40 V

o

150

-65 to 150

260

C/W

o

C

o

C

o

C

Mar. 2011 Rev. 1. 5 BCD Semiconductor Manufacturing Limited

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