XTR108 4-20mA, TWO-WIRE TRANSMITTER
“Smart” Programmable with Signal Conditioning
- COMPLETE TRANSMITTER + RTD
- TWO-WIRE, 4-20mA OUTPUT
- VOLTAGE OUTPUT (0.5V to 4.5V)
- ELIMINATES POTENTIOMETERS AND
- DIGITALLY CALIBRATED
- 5V SUB-REGULATOR OUTPUT
- SERIAL SPI
- BUS INTERFACE
- SSOP-24 PACKAGE
The XTR108 is a “smart,” programmable, 4-20mA, two-wire transmitter designed for temperature and bridge sensors.
Zero, span, and linearization errors in the analog signal path can be calibrated via a standard digital serial interface,
eliminating manual trimming. Non-volatile external EEPROMstores calibration settings.
The all-analog signal path contains an input multiplexer, autozeroed programmable-gain instrumentation amplifier, dual
programmable current sources, linearization circuit, voltage reference, sub-regulator, internal oscillator, control logic, and
an output current amplifier. Programmable level shifting compensates for sensor DC offsets.
Selectable up- and down-scale output indicates out-of-range and burn-out per NAMUR NE43. Automatic reset is initiated when
supply is lost. Current sources, steered through the multiplexer, can be used to directly excite RTD temperature sensors, pressure
bridges, or other transducers. An uncommitted op amp can be used to convert current into a voltage. The XTR108 is
specified for –40°C to +85°C.