ISL43120, ISL43121, ISL43122

9

FN6033.6

August 17, 2015

Submit Document Feedback

Leakage Considerations

Reverse ESD protection diodes are internally connected between

each analog-signal pin and both V+ and GND. One of these diodes

conducts if any analog signal exceeds V+ or GND.

Virtually all the analog leakage current comes from the ESD

diodes to V+ or GND. Although the ESD diodes on a given signal

pin are identical and therefore fairly well balanced, they are

reverse biased differently. Each is biased by either V+ or GND and

the analog signal. This means their leakages will vary as the

signal varies. The difference in the two diode leakages to the V+

and GND pins constitutes the analog-signal-path leakage current.

All analog leakage current flows between each pin and one of the

supply terminals, not to the other switch terminal. This is why both

sides of a given switch can show leakage currents of the same or

opposite polarity. There is no connection between the analog

signal paths and V+ or GND.

FIGURE 9. ON-RESISTANCE vs SUPPLY VOLTAGE

FIGURE 10. ON-RESISTANCE vs SWITCH VOLTAGE

FIGURE 12. CHARGE INJECTION vs SWITCH VOLTAGE

V+ (V)

35

25

15

5

3

4

5

67

89

10

11

12

13

+25°C

-40°C

+85°C

10

20

30

40

15

5

0

468

10

12

10

20

2

20

15

25

10

25

20

30

15

40

45

V+ = 3.3V

V+ = 5V

V+ = 12V

+25°C

-40°C

+85°C

+25°C

-40°C

+85°C

+25°C

-40°C

+85°C

30

35

-40°C

0.10

0

0

4

6

8

10

12

0.05

0.15

2

V+ = 3.3V

V+ = 5V

V+ = 12V

+25°C

-40°C

+85°C

0.10

0.05

0.15

0

0.20

0.25

+25°C

-40°C

+85°C

0.20

0.10

0.30

0

0.40

0.50

+25°C

-40°C

+85°C

+85°C

+25°C

60

40

20

0

-20

0

4

6

8

10

12

-10

10

30

50

V+ = 3.3V

2

V+ = 5V

V+ = 12V