Quintuple/Triple-Output TFT LCD Power Supplies

with Fault Protection and VCOM Buffer

6

_______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (continued)

(Note 3)

PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

NEGATIVE LINEAR-REGULATOR CONTROLLER (REG N)

FBN Regulation Voltage

95

155

mV

FBN Fault Trip Level

325

475

mV

FBN Effective Load Regulation Error

(Transconductance)

30

mV

DRVN Source Current

1

mA

VCOM BUFFER (MAX1997 only)

4.5

13

V

900

µA

Input Offset Voltage

-5

+5

mV

Input Bias Current

1

µA

Input Common-Mode Range

1.2

1.2

V

Out Current Drive

±150

mA

LOGIC SIGNALS (SHDN, ONDC)

Input Low Voltage

100mV typ hysteresis

0.4

V

Input High Voltage

1.6

V

CONTROL INPUTS AND OUTPUTS

FREQ, PFLT Input Low Voltage

1V

FREQ, PFLT Input High Voltage

V

FREQ, PFLT Input Current

FREQ, PFLT = GND or IN

-50

+50

µA

Note 1: Quiescent current does not include switching losses.

Note 2: Guaranteed by design, not production tested.

Note 3: Specifications to -40

°C are guaranteed by design, not production tested.

Note 4: The VCOM buffer load transient settling time is measured with the following circuit:

MAX1997

20k

Ω

20k

Ω

25

Ω

10nF

FBPB

GND

1

µF

1

µF

OUTB

FBNB

8.6V

9V

8V