MAX4617/MAX4618/MAX4619
High-Speed, Low-Voltage, CMOS Analog
Multiplexers/Switches
9
Maxim Integrated
The logic-level thresholds are TTL/CMOS compatible
when V
CC
is +5V. As V
CC
rises, the threshold increas-
es; as V
CC
falls, the threshold decreases. For example,
when V
CC
= +3V the guaranteed minimum logic-high
threshold decreases to 2.0V
Power Supply
These devices operate from a single supply between
+2.5V and +5.5V. All of the bipolar precautions must be
observed. At room temperature, they actually “work”
with a single supply near or below +2V, although as
supply voltage decreases, switch on-resistance
becomes very high.
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 can cause permanent damage to the devices.
Always sequence V
CC
on first, followed by the logic
inputs and analog signals. If power-supply sequencing
is not possible, add two small signal diodes (D1, D2) in
series with the supply pins for overvoltage protection
(Figure 1).
Adding diodes reduces the analog-signal range to one
diode drop below V
CC
and one diode drop above
GND, but does not affect the devices’ low switch resis-
tance and low leakage characteristics. Device opera-
tion is unchanged, and the difference between V
CC
and GND should not exceed 6V. These protection
diodes are not recommended if signal levels must
extend to ground.
High-Frequency Performance
In 50Ω systems, signal response is reasonably flat up
to 50MHz (see
Typical Operating Characteristics
).
Above 20MHz, the on-response has several minor
peaks that 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 frequen-
cies with less attenuation. At 10MHz, off-isolation is
about -50dB in 50Ω systems, becoming worse (approx-
imately 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.
Pin Nomenclature
The MAX4617/MAX4618/MAX4619 are pin compatible
with the industry-standard 74HC4051/74HC4052/
74HC4053 and the MAX4581/MAX4582/MAX4583. In
single-supply applications, they function identically and
have identical logic diagrams, although these parts dif-
fer electrically.
The pin designations and logic diagrams in this data
sheet conform to the original 1972 specifications pub-
lished by RCA for the CD4051/CD4052/CD4053. These
designations differ from the standard Maxim switch and
mux designations found on other Maxim data sheets
(including the MAX4051/MAX4052/MAX4053) and may
cause confusion. Designers who feel more comfortable
with Maxim’s standard designations are advised that
the pin designations and logic diagrams on the
MAX4051/MAX4052/MAX4053 data sheet may be freely
applied to the MAX4617/MAX4618/MAX4619.
