Reference Design  For 4- to 20-mA Loop-Powered RTD Temperature Transmitter

This reference design is extremely appropriate for manufacturing unit automation and course of management functions, sensors and area transmitters, constructing automation, and take a look at and measurement environments. 

In industrial and scientific functions, correct and dependable temperature measurements guarantee optimum efficiency, security, and effectivity. An RTD (Resistance Temperature Detector) temperature transmitter is important on this context. By changing the resistance adjustments of an RTD sensor right into a standardised electrical sign, these transmitters present exact and constant temperature readings. This functionality is indispensable for sustaining course of management in numerous sectors, together with manufacturing, vitality manufacturing, and environmental monitoring. The significance of RTD temperature transmitters lies of their skill to ship high-accuracy measurements, resilience in harsh environments, and integration with trendy digital methods, thus enabling enhanced operational oversight and high quality management.

The Texas Devices (TI) reference design TIDM-01000 gives an environment friendly, low-component, and cost-effective resolution for a 4- to 20-mA loop-powered RTD temperature transmitter. Using the on-chip Sensible Analog Combo (SAC) module throughout the MSP430FR2355 microcontroller (MCU) to handle loop present, it eliminates the necessity for a standalone DAC, attaining exact 12-bit output decision with a 6 µA present decision. It options reverse-polarity safety, complies with IEC61000-4-2 and IEC61000-4-4 requirements, and helps 2-, 3-, or 4-wire RTD probes throughout -200°C to 850°C with lower than 1°C error. The compact design (60mm x 8mm) operates effectively from -40°C to 105°C, leveraging the ultra-low-power MCU’s built-in SAC modules for a dependable and versatile industrial and industrial resolution.

The reference design is structured into three most important blocks, that includes three built-in circuits that type the entire transmitter sign chain. The ADS1220, a high-precision analog-to-digital converter (ADC) from TI, interfaces with the RTD probes, whether or not 2-wire, 3-wire, or 4-wire. The MSP430FR2355 MCU executes the applying firmware, which incorporates algorithms for system calibration and knowledge processing. The on-chip SAC module within the MCU controls the output present, starting from 4 to twenty mA and proportional to the RTD temperature readings. The low-dropout regulator (LDO) TPS7A16 offers loop energy to the system. Notably, the TPS7A16 gadget helps an enter voltage vary of three V to 60 V, options ultra-low quiescent present (5 µA), and is available in excessive thermal-performance packaging, making it a sturdy part for this design.

Texas Devices (TI) has completely examined this reference design, which features a invoice of supplies (BOM), schematics, meeting drawing, and printed circuit board (PCB) format. The corporate’s web site offers further details about this reference design. To study extra, click on right here.