Datasheet

MAX391/MAX392/MAX393
Precision, Quad, SPST Analog Switches
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__________Applications Information
Overvoltage Protection
Proper power-supply sequencing is recommended for
all CMOS devices. Do not exceed the absolute maxi-
mum ratings, because stresses beyond the listed rat-
ings may cause permanent damage to the devices.
Always sequence V+ on first, followed by V-, and then
logic inputs. If power-supply sequencing is not possi-
ble, add two small signal diodes in series with supply
pins for overvoltage protection (Figure 1). Adding
diodes reduces the analog signal range to 1V below V+
and 1V below V-, but low switch resistance and low
leakage characteristics are unaffected. Device opera-
tion is unchanged, and the difference between V+ and
V- should not exceed 17V.
______________________________________________________________Pin Description
POSITIVE SUPPLY
COM
NEGATIVE SUPPLY
NO
V
g
V+
V-
Figure 1. Overvoltage Protection Using Two External Blocking
Diodes
Positive Supply-Voltage Input—connected to substrate
V+13
No Connect—not internally connectedN.C.12
GroundGND5
Negative Supply-Voltage InputV-4
PIN
Switch Inputs
NO1–NO4
or
NC1–NC4
3, 14, 11, 6
Analog Switch Common TerminalCOM1–COM42, 15, 10, 7
InputsIN1–IN41, 16, 9, 8
FUNCTIONNAME