SN55107A, SN75107A, SN75107B, SN75108A

DUAL LINE RECEIVERS

SLLS069D – JANUARY 1977 – REVISED APRIL 1998

17

POST OFFICE BOX 655303

APPLICATION INFORMATION

window detector

The window detector circuit in Figure 21 has a large number of applications in test equipment and in determining

upper limits, lower limits, or both at the same time, such as detecting whether a voltage or signal has exceeded

its window limits. Illumination of the upper-limit (lower-limit) indicator shows that the input voltage is above

(below) the selected upper (lower) limit. A mode selector is provided for selecting the desired test. For window

detecting, the upper-and-lower-limits test position is used.

Mode

Selector

1

2

3

4

500

Ω

500

Ω

5 V – 5 V

1 k

Ω

1 k

Ω

Set

Upper

Limit

Set

Lower

Limit

5 k

Ω

1 k

Ω

Upper-Limit

Indicator

Lower-Limit

Indicator

MODE SELECTOR LEGEND

POSITION

CONDITION

1Off

2

Test for Upper Limit

3

Test for Lower Limit

4

Test for Upper and Lower Limits

5 V

Input From

Test Point

4.7 k

Ω

4.7 k

Ω

4.7 k

Ω

Figure 21. Window Detector Using SN75108A