TFT-LCD Power-Supply Controllers

8

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Pin Description

NAME

PIN

MAX1513

MAX1514

FUNCTION

1

REF

REF

Internal Reference. Connect a 0.22µF ceramic capacitor from REF to the analog ground plane,

which is connected to GND. External load capability is at least 100µA.

2

SDFR

SDFR

LCD Shutdown and Frequency-Select Input.

SDFR = GND, LCD shutdown, REF, buffer amplifier and the logic regulator (REG L) output stay on

SDFR = IN, 1.5MHz switching frequency

SDRF = REF, 750kHz switching frequency

SDFR = unconnected, 430kHz switching frequency

3

FBPB

N.C.

Buffer-Amplifier Noninverting Input for the MAX1513. Not internally connected for the MAX1514.

4

OUTB

N.C.

Buffer-Amplifier Output for the MAX1513. Not internally connected for the MAX1514.

5

SUPB

N.C.

Buffer-Amplifier Supply Input for the MAX1513. Bypass to GND with a 0.1µF capacitor. Not internally

connected for the MAX1514.

6

FBN

FBN

Gate-Off Linear Regulator (REG N) Feedback Input. FBN regulates to 125mV nominal. Connect to

the center tap of a resistive voltage-divider between the REG N output and the reference voltage

(REF) to set the output voltage. Place the resistive-divider close to this pin.

7

DEL

DEL

Delay-Control Timing Capacitor. Connect a capacitor from DEL to GND to set the gate-on linear-

regulator startup delay. See the Power-Up Sequence and Delay Control Block section.

BUFFER-AMPLIFIER LARGE-SIGNAL

STEP RESPONSE

MAX1513/14 toc10

1

µs/div

5V/div

AC-COUPLED

5V/div

AC-COUPLED

BUFFER-AMPLIFIER

LOAD-TRANSIENT RESPONSE

MAX1513/14 toc11

1

µs/div

1V/div

AC-COUPLED

50mA/div

0mA

Typical Operating Characteristics (continued)

wise noted.)