Overview
The XTR106P, produced by Texas Instruments, is a monolithic 4mA to 20mA two-wire current transmitter designed for cost-optimized bridge sensor applications. This device integrates complete bridge excitation, an instrumentation amplifier, sensor linearization, and current output circuitry. It is particularly suited for applications requiring high accuracy and low drift over a wide range of temperatures and supply voltages.
The XTR106P operates on loop power supply voltages down to 7.5V and is available in 14-pin plastic DIP and SOIC surface-mount packages. It is specified for the –40°C to +85°C temperature range, with operation possible up to +125°C. The device features second-order correction to the transfer function, significantly improving nonlinearity even with cost-optimized transducers.
Key Specifications
| Parameter | Min | Typ | Max | Units |
|---|---|---|---|---|
| Output Current Range | 4 | 20 | mA | |
| Overscale Limit | 24 | 30 | mA | |
| Underscale Limit | 1 | 2.2 | mA | |
| Zero Output Current | 4 | mA | ||
| Initial Error | ±5 | ±25 | μA | |
| Span Drift | ±3 | ±25 | ppm/°C | |
| Offset Drift | ±0.25 | ±1.5 | μV/°C | |
| PSR (Power Supply Rejection Ratio) | 110 | dB | ||
| CMR (Common Mode Rejection Ratio) | 86 | dB | ||
| Supply Voltage Range | 7.5 | 36 | V | |
| Package Options | 14-pin DIP, 14-pin SOIC |
Key Features
- Low total unadjusted error and low span drift (±25ppm/°C maximum)
- Low offset drift (0.25μV/°C)
- High PSR (110dB minimum) and CMR (86dB minimum)
- Wide supply range (7.5V to 36V)
- 2.5V and 5V bridge excitation references
- 5.1V regulator output
- Second-order correction for bridge nonlinearity
- High input impedance instrumentation amplifier with adjustable gain
- Available in 14-pin DIP and SOIC packages
Applications
- Field transmitter and sensor applications
- Factory automation and industrial process control
- Pressure and temperature bridge transmitters
- SCADA remote data acquisition
- Weighing systems and strain gauge transmitters
- Accelerometers and compatible with HART modem
Q & A
- What is the primary function of the XTR106P?
The XTR106P is a 4mA to 20mA two-wire current transmitter designed for bridge sensor applications, integrating bridge excitation, an instrumentation amplifier, sensor linearization, and current output circuitry.
- What are the available package options for the XTR106P?
The XTR106P is available in 14-pin plastic DIP and 14-pin SOIC surface-mount packages.
- What is the operating temperature range of the XTR106P?
The device is specified for the –40°C to +85°C temperature range, with operation possible up to +125°C.
- What is the minimum supply voltage required for the XTR106P?
The minimum supply voltage is 7.5V.
- How does the XTR106P correct for bridge nonlinearity?
The XTR106P features second-order correction to the transfer function, which can be set using the linearity correction circuit polarity and resistor settings.
- What are the typical applications of the XTR106P?
Typical applications include field transmitter and sensor, factory automation, pressure and temperature bridge transmitters, SCADA remote data acquisition, weighing systems, and strain gauge transmitters.
- How does the XTR106P handle radio frequency interference?
RF interference can be mitigated by using bypass capacitors on the input and ensuring proper wiring and grounding practices.
- Can the XTR106P operate without an external pass transistor?
Yes, but accuracy may be degraded due to internal power dissipation and self-heating. Operation without an external transistor is not recommended for extended temperature ranges.
- What is the significance of the 5.1V regulator output in the XTR106P?
The 5.1V regulator output provides power for additional external input circuitry.
- How does the instrumentation amplifier in the XTR106P contribute to its versatility?
The high input impedance instrumentation amplifier can be configured for differential input voltages from millivolts to a maximum of 2.4V full scale, accommodating a variety of input signal types and sensors.
