AIM AT1741 Datasheet

AT1741

2-Channel PWM Controller for CCFL Backlight

Features

• High-accuracy reference voltage circuit (±2%).

• Built-in short-circuit protection circuit.

• Built-in Undervoltage Lockout protection.

• Internal 2.5V Reference supply.

• Variable Dead time provides control over total
Range.

Applications

• LCD CCFL Backlight

• Portable equipment

Block Diagram

General Description

The AT1741 is 2-channel PWM switching
regulator controllers that contains an on-chip 2.5V
reference, two error amplifier, an adjustable
oscillator, two dead-time comparators, under­voltage lockout circuitry and 2 common-emitter
output. It is idea for step-up, step-down, and
inverting converter.

2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: [phone] WWW: http://www.aimtron.com.tw
Fax: [phone] Email: [e-mail]

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AT1741

2-Channel PWM Controller for CCFL Backlight

Pin Configuration

Ordering Information

Part number Package Marking

AT1741 SOP16 AT1741S

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Pin Description

Pin No. Symbol I/O Description

1 CT -- External timing capacitor
2 RT -- External timing resistor
3 NON1 I Positive input for error amplifier 1
4 INV1 I Negative input for error amplifier 1
5 FB1 O Error amplifier 1 output
6 DT1 I Output 1 dead time / soft start setting
7 OUT1 O Output 1
8 GND -- Ground

9 Vcc -- Power supply
10 OUT2 O Output 2
11 DT2 I Output 2 dead time / soft start setting
12 FB2 O Error amplifier 2 output
13 INV2 I Negative input for error amplifier 2
14 NON2 I Positive input for error amplifier 2
15 SCP -- Time latch setting
16 Vref O

Reference voltage output（2.5V）

2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: [phone] WWW: http://www.aimtron.com.tw
Fax: [phone] Email: [e-mail]

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AT1741

2-Channel PWM Controller for CCFL Backlight

Absolute Maximum Ratings

(Ta=+250C)

Parameter Symbol

Power supply voltage Vcc 30 V
Power dissipation Pd 500*
Operating temperture Topr -30~+85

Storage temperture Tstg -55~+125
Output current Io 120*

Output voltage Vo 30

＊1 When mounted on 70mm×70mm×1.6mm glass epoxy board. Reduced by 6.5mw for each increase in Ta of 1℃ over 25℃.
＊2 Should not exceed Pd and values.

Limits

Unit

1

mW

℃
℃

2

mA

V

Recommended Operating Conditions

(Ta=+250C)

Va lu esParameter Symbol

Min. Typ. Max.

Power supply voltage V

CC

3.6 6.0 25

Output current Io -- -- 100 mA
Output voltage Vo -- -- 25 V
Error amplifier input voltage V
Timing capacitor C
Timing resistor
Oscillator frequency F

OM

CT

R

RT

OSC

0.3 -- 1.6 V

100 -- 15000 pF

5.1 -- 50
10 -- 800 kHz

Unit

Ｖ

kΩ

Timing chart

2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: [phone] WWW: http://www.aimtron.com.tw
Fax: [phone] Email: [e-mail]

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