Voltage Regulators

1

AN8041S

Liquid crystal backlight control IC

s Overview

The AN8041S is an inverter control IC for liquid

crystal backlight using PWM method. The output

voltage of DC-DC converter and the current of cath-

ode-ray tube can be controlled by using two error

amplifiers, so that the system is designed easily.

Since the n-channel MOSFET can be directly

driven, it is possible to construct a highly effective

power supply.

s Features

• Totem pole output circuit: Output current of ±500 mA

• Built-in bootstrap circuit

• N-channel power MOSFET can be directly driven

• Built-in two error amplifier circuits allow both the

voltage and current control

• Incorporating on/off functions (active-high control input, standby mode current is 5 µA or less)

• Built-in timer latch short-circuit protection circuit

• Maximum oscillation frequency: 500 kHz

Note) *: The voltage is limited to the range of 3.6 V to 17 V if used in a step-down circuit.

s Applications

• LCD displays, digital still cameras, and PDAs

s Block Diagram

SOP016-P-0225A

Unit: mm

0.3

(0

° to 10°)

Seating plane

10.1±0.3

18

16

9

1.27

(0.605)

Seating plane

0.40±0.25

CB

14

Out

13

FB1

8

IN

+1

6

IN

−1

7

S.C.P.

5

Off

16

S.C.P.

comp.

Q

Q

R

S

Bootstrap

Constant

current source

OSC

2.57 V

On/off

active-high

PWM comp.

Error amp. 2

U.V.L.O.

Q

R

S

Latch

Error amp. 1

FB2

9

IN

+2

11

IN

−2

10