MP1531 – LOW POWER, TRIPLE OUTPUT STEP-UP PLUS CHARGE PUMP FOR TFT BIAS

MP1531 Rev. 1.2

www.MonolithicPower.com

3

5/22/2006

MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.

© 2006 MPS. All Rights Reserved.

ELECTRICAL CHARACTERISTICS

Parameter

Symbol Condition

Min

Typ

Max

Units

Oscillator

Switching Frequency

200

250

300

KHz

Maximum Duty Cycle

85

90

%

Soft-Start Period

C4 = 10nF

6

ms

Turn-Off Delay

3

µs

Error Amplifier

Error Amplifier Voltage Gain

400

V/V

Error Amplifier Transconductance

1000

µA/V

COMP Maximum Output Current

±100

µA

FB1, FB3 Regulation Voltage

1.22

1.25

1.28

V

FB2 Regulation Voltage

–25

0

+25

mV

FB1, FB3 Input Bias Current

±100

nA

FB2 Input Bias Current

±100

nA

Reference (REF)

REF Regulation Voltage

1.22

1.25

1.28

V

REF Load Regulation

1

1.2

%

Output Switch (SW)

250

mΩ

SW On Resistance

400

mΩ

SW Current Limit

0.5

0.65

A

SW Leakage Current

0.5

1

µA

GL Dropout Voltage

(5)

0.15

V

GH Dropout Voltage

(5)

0.5

V

GL Leakage Current

1

µA

GH Leakage Current

1

µA

Thermal Shutdown

160

°C

Notes:

4) Typical values are guaranteed by design, not production tested.

5) Dropout voltage is the input to output differential at which the circuit ceases to regulate against further reduction in input voltage.

TYPICAL PERFORMANCE CHARACTERISTICS

Circuit of Figure 3, unless otherwise noted.

100

90

80

70

60

50

40

30

20

0

100 200 300 400 500 600

LOAD CURRENT (mA)

Efficiency vs Load Current

Delivered by Step-Up Converter

Power-Up Sequencing

50mA/div

50mV/div

5V/div

Load Transient

5V/div

10V/div

10V/div

10ms/div