MAX4529ESA Maxim Integrated Products, MAX4529ESA Datasheet - Page 8

• Manufacturer Part Number: MAX4529ESA
• Description: IC VIDEO SWITCH SPST 8SOIC
• Manufacturer: Maxim Integrated Products

Specifications of MAX4529ESA

• Function: Video Switch
• Circuit: 1 x SPST- NC
• On-state Resistance: 120 Ohm
• Voltage Supply Source: Single, Dual Supply
• Voltage - Supply, Single/dual (±): 2.7 V ~ 12 V, ± 2.7 V ~ 6 V
• Current - Supply: 50µA
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (0.154", 3.90mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Low-Voltage, Bidirectional
RF/Video Switch
The MAX4529 is a optimized for ±5V operation. Using
lower supply voltages or a single supply increases
switching time, on-resistance (and therefore on-state
attenuation), and nonlinearity.
When the switch is off, MOSFETs N1, N2, P1, and P2
are off and MOSFET N3 is on. The signal path is
through the off-capacitances of the series MOSFETs,
but it is shunted to ground by N3. This forms a high-
pass filter whose exact characteristics depend on the
source and load impedances. In 50Ω systems, and
below 10MHz, the attenuation can exceed 80dB. This
value decreases with increasing frequency and
increasing circuit impedances. External capacitance
and board layout have a major role in determining over-
all performance.
The MAX4529’s construction is typical of most CMOS
analog switches. It has three supply pins: V+, V-, and
GND. V+ and V- are used to drive the internal CMOS
switches and set the limits of the analog voltage on any
switch. Reverse ESD protection diodes are internally
connected between each analog signal pin and both
V+ and V-. If the voltage on any pin exceeds V+ or V-,
one of these diodes will conduct. During normal opera-
tion these reverse-biased ESD diodes leak, forming the
only current drawn from V-.
Virtually all the analog leakage current is through the
ESD diodes. Although the ESD diodes on a given sig-
nal pin are identical, and therefore fairly well balanced,
they are reverse biased differently. Each is biased by
either V+ or V- and the analog signal. This means their
leakages vary as the signal varies. The difference in the
two diode leakages from the signal path to the V+ and
V- pins constitutes the analog signal-path leakage cur-
rent. All analog leakage current flows to the supply ter-
minals, not to the other switch terminal. This explains
how both sides of a given switch can show leakage
currents of either the same or opposite polarity.
When the switch is on, there is no connection between
the analog signal paths and GND. The analog signal
paths consist of an N-channel and P-channel MOSFET
with their sources and drains paralleled and their gates
driven out of phase with V+ and V- by the logic-level
translators.
V+ and GND power the internal logic and logic-level
translators, and set the input logic thresholds. The
logic-level translators convert the logic levels to
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Applications Information
Power-Supply Considerations
Switch Off Condition
Overview
switched V+ and V- signals to drive the gates of the
analog switches. This drive signal is the only connec-
tion between the logic supplies and the analog sup-
plies. All pins have ESD protection to V+ and to V-.
Increasing V- has no effect on the logic-level thresh-
olds, but it does increase the drive to the P-channel
switches, reducing their on-resistance. V- also sets the
negative limit of the analog signal voltage.
The logic-level thresholds are CMOS and TTL compati-
ble when V+ is +5V. As V+ is raised, the threshold
increases slightly; when V+ reaches +12V, the level
threshold is about 3.1V, which is above the TTL output
high-level minimum of 2.8V, but still compatible with
CMOS outputs.
The MAX4529 operates with bipolar supplies between
±2.7V and ±6V. The V+ and V- supplies need not be
symmetrical, but their sum cannot exceed the absolute
maximum rating of 13.0V. Do not connect the
MAX4529 V+ pin to +3V and connect the logic-level
input pins to TTL logic-level signals. TTL logic-level
outputs can exceed the absolute maximum ratings,
causing damage to the part and/or external circuits.
The MAX4529 operates from a single supply between
+2.7V and +12V when V- is connected to GND. All of
the bipolar precautions must be observed. Note, how-
ever, that these parts are optimized for ±5V operation,
and most AC and DC characteristics are degraded sig-
nificantly when departing from ±5V. As the overall sup-
ply voltage (V+ to V-) is lowered, switching speed,
on-resistance, off isolation, and distortion are degraded
(see Typical Operating Characteristics).
Single-supply operation also limits signal levels and
interferes with grounded signals. When V- = 0V, AC sig-
nals are limited to -0.3V. Voltages below -0.3V can be
clipped by the internal ESD-protection diodes, and the
parts can be damaged if excessive current flows.
CAUTION:
The absolute maximum V+ to V- differential
voltage is 13.0V. Typical “±6-Volt” or “12-Volt”
supplies with ±10% tolerances can be as high
as 13.2V. This voltage can damage the
MAX4529. Even ±5% tolerance supplies may
have overshoot or noise spikes that exceed
13.0V.
Bipolar-Supply Operation
Single-Supply Operation