Diodes AP3612 User Manual

Boost Type LED Driver with 12-Channel Current Source AP3612

Preliminary Datasheet

General Description

The AP3612 is a high efficiency boost controller with
12-string current sources for driving WLED backlight.
It operates over a wide input voltage range from 4.5V
to 33V.

The current of 12 strings are simply programmed
from 20mA to 75mA with an external resistor. The
current matching between each string is 1.5% (Typ).
Its operating frequency can be adjusted from 0.1MHz
to 1MHz.

The AP3612 features Cycle-by-cycle Current Limit,
Soft Start, Under Voltage Lock Out (UVLO)
protection, programmable OVP, Over Temperature
Protection (OTP), open/short LED protection, V
short protection and Schottky diode short-circuit
protection.

The AP3612 is available in HSOP-28 and SOIC-24
packages.

OUT

Features

• Input Voltage Range: 4.5V to 33V

• Drives up to 12 Strings in Parallel, 75mA per
String

• Programmable WLED Current from 20mA to

75mA

• Adjustable Operating Frequency: 100kHz to
1MHz

• String-to-string Current Matching Accuracy:

1.5%

• Built-in OCP, OTP, UVLO

• External PWM Dimming

• Open/Short LED Protection

• Programmable Soft Start

• Programmable OVP

• Schottky Diode/Inductor Short-circuit Protection

• V

Short/Schottky Diode Open Protection

OUT

Applications

• LCD Monitor

• LCD Display Module

• LCD TV

HSOP-28 SOIC-24

Figure 1. Package Types of AP3612

Aug. 2012 Rev. 1. 1 BCD Semiconductor Manufacturing Limited

1

Preliminary Datasheet

Boost Type LED Driver with 12-Channel Current Source AP3612

Pin Configuration

M28 Package M Package

(HSOP-28) (SOIC-24)

CH2
CH3
CH4
CH5
CH6

NC

GND

CH7
CH8

CH9
CH10
CH11

ISET

CH12

1

2

3

4

5

6

7

8

9

10

11

12

13

14

28

27

26

25

24

23

22

21

20

19

18

17

16

15

CH1
DIM
COMP

NC
STATUS

VIN
VCC

NC

GND

OUT
CS
EN
RT
OVP

CH7
CH8

CH9
CH10
CH11

ISET

CH12

OVP

RT

EN
CS

OUT

10
11
12

1

2

3

4

5

6

7

8

9

24
23
22
21
20

19
18

17
16
15
14
13

GND
CH6

CH5
CH4

CH3
CH2
CH1
DIM
COMP
STATUS

VIN
VCC

Figure 2. Pin Configuration of AP3612 (Top View)

Aug. 2012 Rev. 1. 1 BCD Semiconductor Manufacturing Limited

2

µ

Preliminary Datasheet

Boost Type LED Driver with 12-Channel Current Source AP3612

Pin Description

Pin Number

HSOP-28 SOIC-24

28,1,2,3,4,5,

8,9,10,11,12 ,14

6, 21,25

7, 20 24 GND

13

15

16

17 10 EN

18 11 CS

19 12 OUT

22 13 VCC

23 14 VIN

24 15 STATUS
26 16 COMP

27 17 DIM

18,19,20,21, 22,23,

1, 2, 3, 4, 5, 7

6

8 OVP

9

Pin Name Function

CH1 to CH12

NC

ISET

RT

LED current sink. Leave the pin open directly
if not used

No connection

Ground pin

LED current setting pin. The corresponding
maximum current of all strings is set through
connecting a resistor from this pin to GND
Over voltage protection pin. When the OVP
pin voltage exceeds 2.0V, the OVP is triggered
and the power switch is turned off. When the
OVP pin voltage drops below hysteresis
voltage, the OVP is released and the power
switch will resume normal operation

Frequency control pin

ON/OFF control pin. Forcing this pin above

2.4V enables the IC while below 0.5V shuts
down the IC. When the IC is in shutdown
mode, all functions are disabled to decrease
the supply current below 3µA

Power switch current sense input
Boost converter power switch gate output.

This pin output high voltage (5V/V
drive the external N-MOSFET
5V linear regulator output pin. This pin should
be bypassed to GND (recommend to connect
with GND pin) with a ceramic capacitor
Supply input pin. A capacitor (typical 10
should be connected between the VIN and
GND to keep the DC input voltage constant

LED operation status output
Soft-start and control loop compensation
PWM dimming control pin. Adding a PWM

signal to this pin to control LED dimming. If
not used, connect it to the high level

-0.5V) to

IN

F)

Aug. 2012 Rev. 1. 1 BCD Semiconductor Manufacturing Limited

3

Preliminary Datasheet

Boost Type LED Driver with 12-Channel Current Source AP3612

Functional Block Diagram

Figure 3. Functional Block Diagram of AP3612

Aug. 2012 Rev. 1. 1 BCD Semiconductor Manufacturing Limited

4

Preliminary Datasheet

Boost Type LED Driver with 12-Channel Current Source AP3612

Ordering Information

AP3612 -

Circuit Type

Package
M28: HSOP-28
M: SOIC-24

G1: Green

Blank: Tube

Package

HSOP-28

SOIC-24 AP3612M-G1 AP3612M-G1 Tube

Temperature

Range

-40 to 85°C

Part Number Marking ID Packing Type

AP3612M28-G1 AP3612M28-G1 Tube

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

CH1 to CH12 Voltage

EN Pin Voltage

VCC Pin Voltage

CS Pin Voltage

COMP Pin Voltage

ISET Pin Voltage

OUT Pin Voltage

OVP Pin Voltage

RT Pin Voltage

STATUS Pin Voltage

DIM Pin Voltage

GND Pin Voltage

Thermal Resistance
(Junction to Ambient,
Free Air, No Heatsink)

HSOP-28

SOIC-24 100

V

V

V

V

V

V

COMP

V

V

V

V

V

STATUS

V

V

θ

IN

CH

EN

CC

CS

ISET

OUT

OVP

RT

DIM

GND

JA

Aug. 2012 Rev. 1. 1 BCD Semiconductor Manufacturing Limited

5

-0.3 to 42 V

-0.3 to 65 V

-0.3 to 7 V

-0.3 to 7 V

-0.3 to 7 V

-0.3 to 7 V

-0.3 to 7 V

-0.3 to 7 V

-0.3 to 7 V

-0.3 to 7 V

-0.3 to 7 V

-0.3 to 7 V

-0.3 to 0.3 V

59

ºC/W

Preliminary Datasheet

Boost Type LED Driver with 12-Channel Current Source AP3612

Absolute Maximum Ratings (Note 1) (Continued)

Parameter Symbol Value Unit

Operating Junction Temperature

Storage Temperature

Lead Temperature
(Soldering, 10sec)

ESD (Machine Model) 200 V

ESD (Human Body Model) 2000 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: Negative CS 100ns Transient maximum rating voltage reach to -0.4V.

T

T

T

J

STG

LEAD

150 ºC

-65 to 150 ºC

260 ºC

Recommended Operating Conditions

Parameter Symbol Min Max Unit

Input Voltage V

Operating Frequency fO 0.1 1 MHz

LED Channel Voltage V

LED Channel Current I

PWM Dimming Frequency f

Operating Ambient Temperature
Range

IN

60 V

CHX

20 75 mA

CHX

0.1 20 kHz

PWM

-40 85 ºC

T

A

4.5 33 V

Aug. 2012 Rev. 1. 1 BCD Semiconductor Manufacturing Limited

6