8

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 7. ON RESISTANCE vs SUPPLY VOLTAGE

FIGURE 8. ON RESISTANCE vs SWITCH VOLTAGE

FIGURE 9. CHARGE INJECTION vs SWITCH VOLTAGE

FIGURE 10. DIGITAL SWITCHING POINT vs SUPPLY VOLTAGE

V+ (V)

25

15

5

3

4

5

6

7

8

9

10

11

12

13

10

20

0

4

6

8

10

12

2

4

6

8

10

12

14

V+ = 12V

10

15

20

25

V+ = 3.3V

7

9

11

13

15

17

19

V+ = 5V

012

34

5

0

10

20

30

40

50

V+ = 3.3V

V+ = 5V

V+ (V)

25

3.0

2.5

2.0

1.5

1.0

0.5

34

6789

10

11

12

13

ISL84514, ISL84515