MAX4644
High-Speed, Low-Voltage, 4
Ω
,
SPDT CMOS Analog Switch
_______________________________________________________________________________________ 7
Applications Information
The MAX4644 operates from a single supply ranging
from +1.8V to +5.5V. The device is guaranteed to be
functional over that supply range, but TTL/CMOS com-
patibility is only valid for operation using a +5V supply.
All voltage levels are referenced to GND. Positive and
negative DC analog inputs or AC signals can be
accommodated by shifting V+ and GND.
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 (Figure 1). Virtually all of the ana-
log 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 consti-
tutes 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 cur-
rents of the same or opposite polarity.
There is no normal current path between the analog-
signal paths and V+ or GND. V+ and GND also power
the internal logic and logic-level translators. The logic-
level translators convert the logic level into switched V+
and GND signals to drive the analog signal gates.
Chip Information
PROCESS: BiCMOS
Package Information
For the latest package outline information and land patterns
(footprints), go to www.maxim-ic.com/packages
. Note that a
“+”, “#”, or “-” in the package code indicates RoHS status only.
Package drawings may show a different suffix character, but
the drawing pertains to the package regardless of RoHS status.
V+
N0, NC
GND
COM
Figure 1. Overvoltage Protection Using External Blocking
Diodes
PACKAGE
TYPE
PACKAGE
CODE
OUTLINE
NO.
LAND
PATTERN NO.
6 SOT23 U6+4
21-0058 90-0175
8 μMAX U8+1
21-0036 90-0092
