Complete Bias and White LED Power Supplies

for Small TFT Displays

6

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-5.0

-3.5

-4.0

-4.5

-3.0

-2.5

-2.0

-1.5

-1.0

POS

NEG

-0.5

0

040

20

60

80

100

POS AND NEG LOAD REGULATION

LOAD CURRENT (

µA)

-0.6

-0.4

-0.5

-0.2

-0.3

-0.1

0

025

MAIN OUTPUT LOAD REGULATION

LOAD CURRENT (mA)

10

515

20

PIN

NAME

FUNCTION

1

MAIN

with a 1µF capacitor. Output is internally discharged with a 1k

2

CU1

POS Charge-Pump Capacitor Connection 1. Connect a 1µF capacitor between CU1 and PMP.

3

CU2

POS Charge-Pump Capacitor Connection 2. Connect a 1µF capacitor between CU2 and PMPB.

4

CU3

POS Charge-Pump Capacitor Connection 3. Connect a 1µF capacitor between CU3 and GND.

5

POS

Output of Positive (3x) Charge Pump. Bypass POS to GND with a 1µF capacitor. POS is internally

discharged with a 3k

6PMP

Charge-Pump Capacitor Connection. Connect a 1µF capacitor between PMP and CU1 and another

1µF capacitor between PMP and CD1.

7

PMPB

Charge-Pump Capacitor Connection. Connect a 1µF capacitor between PMPB and CU2 and another

1µF capacitor between PMPB and CD2. PMPB is 180

° out of phase with PMP.

8

CD1

NEG Charge-Pump Capacitor Connection 1. Connect a 1µF capacitor and a 200

Ω ±5% resistor in

series between CD1 and PMP.

9

CD2

NEG Charge-Pump Capacitor Connection 2. Connect a 1µF capacitor and a 200

Ω ±5% resistor in

series between CD2 and PMPB.

10

NEG

Output of Inverting (-2x) Charge Pump. Bypass NEG to GND with a 1µF capacitor. Output is internally

discharged with a 1.5k

Pin Description

Typical Operating Characteristics (continued)

°C, unless otherwise noted.)