10

LTC1040

1040fa

TYPICAL APPLICATIO S

Figure 10. The LTC1040 as a Linear Amplifier

LTC1040 • TA07

–

–

+

+

1/2 LTC1040

C

R

0V

LTC1040 • TA08

The LTC1040 as a Linear Amplifier

With a simple RC filter, the LTC1040 can be made to

function as a linear amplifier. By filtering the logic output

and feeding it back to the negative input, the loop forces

The RC time constant is set to keep the ripple on the output

small. The maximum output ripple is:

should be set to 0.5mV to 1mV for best results. Notice that

This is important because the RC filter also sets the loop

under all conditions is to connect a 100k resistor to pin 16

(OSC) with no capacitance to ground.

2-Wire 0

°C to 100°C Temperature Transducer with 4mA to 20mA Output

LTC1040 • TA09

6

5

7

8

10

9

18

4 1M

16

††

+

+

–

–

1/2

LTC1040

†

6

4

1k

ZERO

ADJUST

100k

3200

18k

LT1019-5

6250

YELLOW SPRINGS INSTRUMENT

PART NO. 44201

1

µF

10

µF

FULL-SCALE

ADJUST

ACCURACY =

+

=

±0.3°C

±0.1°C

CIRCUIT ERROR

AT 25

°C

±0.2°C

TRANSDUCER

ERROR

5k

182

Ω

50

Ω

2N6657

1N914

LM134

430

Ω

43

R

12V TO 40V

0

°C = 4mA

100

°C = 20mA

RETURN

+

+