1

LTC1408-12

140812f

6 Channel, 12-Bit, 600ksps

Simultaneous Sampling ADC

with Shutdown

The LTC

simultaneously sampled differential inputs. The device

draws only 5mA from a single 3V supply, and comes in a

tiny 32 pin (5mm

× 5mm) QFN package. A SLEEP shut-

down feature further reduces power consumption to

6

µW. The combination of low power and tiny package

makes the LTC1408-12 suitable for portable applications.

The LTC1408-12 contains six separate differential inputs

that are sampled simultaneously on the rising edge of the

CONV signal. These six sampled inputs are then

converted at a rate of 100ksps per channel.

The 83dB common mode rejection allows users to

eliminate ground loops and common mode noise by

measuring signals differentially from the source.

The device converts 0V to 2.5V unipolar inputs differen-

tially, or

±1.25V bipolar inputs also differentially,

depending on the state of the BIP pin. Any analog input

may swing rail-to-rail as long as the differential input

range is maintained.

The conversion sequence can be abbreviated to convert

fewer than six channels, depending on the logic state of

the SEL2, SEL1 and SEL0 inputs.

The serial interface sends out the six conversion results in

96 clocks for compatibility with standard serial interfaces.

Differential Inputs

with External Reference

±1.25V Bipolar Differential

Input Range

µW) Shutdown Mode

■

Multiphase Motor Control

APPLICATIO S

FEATURES

DESCRIPTIO

BLOCK DIAGRA

–

4

5

25

24

–

7

6

9

12

13

16

19

8

10

11

–

14

15

–

17

18

–

20

21

S AND H

S AND H

S AND H

S AND H

S AND H

MUX

10

µF

BIP

SEL2 SEL1 SEL0

GND

2.5V

REFERENCE

600ksps

12-BIT ADC

12-BIT LATCH 5

12-BIT LATCH 4

12-BIT LATCH 3

12-BIT LATCH 2

12-BIT LATCH 1

12-BIT LATCH 0

10

µF3V

26

29

23

22

33

27

28

2

1

SD0

0.1

µF

3

3V

32

SCK

31

DGND

OGND

30

CONV

THREE-

STATE

SERIAL

OUTPUT

PORT

TIMING

LOGIC

235114 TA01

–

S AND H

, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.

All other trademarks are the property of their respective owners.

Protected by U.S. Patents including 6084440, 6522187.