UC3704
Bridge Transducer Switch
DESCRIPTION
FEATURES
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Dual Matched Current Sources
This integrated circuit contains a complete signal conditioning sys-
tem to interface low-level variable impedance transducers to a
digital system. A pair of matched, temperature-compensated cur-
rent sources are provided for balanced transducer excitation fol-
lowed by a precision, high-gain comparator. The output of this
comparator can be delayed by a user-selectable duration, after
which a second comparator will switch complementary outputs
separately activated for diagnostic operation and has an optional
latch with external reset capability. An added feature is a high cur-
rent power source useful as a heater driver in differential tempera-
ture sensing applications. The UC3704 is designed for 0°C to
+70°C environments.
High-gain Differential Sensing Circuit
Wide Common-mode Input Capability
Complementary Digital Open-collector
Outputs
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Externally Programmable Time Delay
Optional Output Latch with Reset
Built-in Diagnostic Activation
Wide Supply Voltage Range
High Current Heater Power Source Driver
UC3704 COMPATIBLE SENSORS
SENSOR TYPE
ACTIVATION SOURCE
Temperature
Pressure
Force
X
Position
Displacement
Velocity
Shock
Thermistor
X
X
X
X
X
X
Sensistor
Thermocouple
Semiconductor
Photo Voltaic
Photo Resistive
Strain Gage
Piezoelectric
Magneto Resistive
Inductive
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Hall Effect
Capacitive
BLOCK DIAGRAM
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