6

LTC1451

LTC1452/LTC1453

GND: Ground.

REF: The Output of the Internal Reference and the Input

to the DAC Resistor Ladder. An external reference with

(LTC1451), 2.7

quires a bypass capacitor to ground.

CLK: The TTL Level Input for the Serial Interface Clock.

edge of the serial clock.

CS/LD: The TTL Level Input for the Serial Interface Enable

and Load Control. When CS/LD is low the CLK signal is

enabled, so the data can be clocked in. When CS/LD is

pulled high, data is loaded from the shift register into the

DAC register, updating the DAC output.

Valid on the Rising Edge of the Serial Clock.

B11

MSB

B10

B1

B0

LSB

B11

CURRENT WORD

CLK

CS/LD

1451/2/3 TD

B0

PREVIOUS WORD

B11

PREVIOUS WORD

B10

B1

B0

DAC

REGISTER

LD

+

–

REFERENCE

LTC1451: 2.048V

LTC1453: 1.22V

12-BIT

SHIFT

REGISTER

POWER-ON

RESET

11451/2/3 BD

CLK 1

7

REF

6

GND

5

8

3

CS/LD

12-BIT DAC

PI FU CTIO S

BLOCK DIAGRA

TI I G DIAGRA