6

LT1719

TEST CIRCUITS

+

–

–

+

DUT

LT1719

BANDWIDTH-LIMITED TRIANGLE WAVE

LTC203

1/2 LT1112

50

Ω

100k

100k

2.4k

10nF

1

µF

0.15

µF

1/2 LT1638

1/2 LT1638

100k

100k

200k

10k

10k

1000

1000

1000

1000

0.1

µF

50

Ω

50k

+

–

1/2 LT1112

1719 TC01

10nF

1

µF

NOTES: LT1638, LT1112, LTC203s ARE POWERED FROM

±15V.

200k

Ω PULL-DOWN PROTECTS LTC203 LOGIC INPUTS

WHEN DUT IS NOT POWERED

15

3

2

14

16

9

1

8

10

6

7

11

LTC203

2

14

15

3

1

8

16

9

7

11

10

6

Power Supply Configurations

The LT1719 has separate supply pins for the input and

output stages that allow flexible operation, accommodat-

ing separate voltage ranges for the analog input and the

output logic. Of course, a single 3V/5V supply may be used

The minimum voltage requirement can be simply stated as

both the output and the input stages need at least 2.7V and

The following rules must be adhered to in any

configuration:

2.7V

2.7V

Although the ground pin need not be tied to system

ground, most applications will use it that way. Figure 1

shows three common configurations. The final one is

uncommon, but it will work and may be useful as a level

translator; the input stage is run from – 5.2V and ground

while the output stage is run from 3V and ground. In this

case the common mode input voltage range does not

as long as the above rules are not violated.

Input Voltage Considerations

The LT1719 is specified for a common mode range of

–100mV to 3.8V when used with a single 5V supply. A

more general consideration is that the common mode

for this common mode limit is that the output still