MAX4525 Maxim, MAX4525 Datasheet - Page 8

• Manufacturer Part Number: MAX4525
• Description: The MAX4524/MAX4525 are low-voltage, single-supply CMOS analog switches configured as a 4-channel multiplexer/demultiplexer (MAX4524) and a double-pole/double-throw (DPDT) switch (MAX4525)
• Manufacturer: Maxim

There is no connection between the analog signal
paths and GND. V+ and GND power the internal logic
and logic-level translators, and set both the input and
output logic limits. The logic-level translators convert
the logic levels into switched V+ and GND signals to
drive the gates of the analog signals. This drive signal
is the only connection between the logic supplies (and
signals) and the analog supplies. V+ has an ESD-pro-
tection diode to GND.
These devices operate from a single supply between
+2V and +12V. At room temperature, they actually
“work” with a single supply at near or below +1.7V,
although as supply voltage decreases, switch on-resis-
tance and switching times become very high.
Low-Voltage, Single-Supply
Multiplexer and Switch
_________________________________Test Circuits/Timing Diagrams (continued)
Figure 2. Inhibit Switching Times
8
_______________________________________________________________________________________
REPEAT TEST FOR EACH SECTION.
V
V
INH
INH
50
50
ADD
ADDA
INH
ADDB
INH
MAX4525
MAX4524
Low-Voltage Operation
GND
GND
V+
V+
V+
V+
NO1–NO3
COM_
COM
NO_
NC_
NO0
300
300
V+
V+
35pF
35pF
V
V
OUT
OUT
In 50
to 50MHz (see Typical Operating Characteristics).
Above 20MHz, the on-response has several minor
peaks, which are highly layout dependent. The problem
is not turning the switch on, but turning it off. The off-
state switch acts like a capacitor, and passes higher
frequencies with less attenuation. At 10MHz, off-isola-
tion is about -50dB in 50
(approximately 20dB per decade) as frequency
increases. Higher circuit impedances also degrade off-
isolation. Adjacent channel attenuation is about 3dB
above that of a bare IC socket, and is entirely due to
capacitive coupling.
V
V
V
V
OUT
INH
INH
OUT
V
systems, signal response is reasonably flat up
V
NO_
NO0
V+
0V
V+
0V
0V
0V
t
t
ON
ON
High-Frequency Performance
50%
50%
90%
90%
systems, becoming worse
90%
90%
t
t
OFF
OFF