Today, system designers must develop enhanced 4-20 mA sensor transmitters with several considerations in mind. These include improved measurement accuracy over a wide temperature range and a smaller size to fit in confined spaces. Furthermore, they are required to meet a tight limit on the total sensor transmitter system current of 4 mA maximum.
The MAX12900 enhances system accuracy with a 10 ppm/°C voltage reference for 3.5 times lower drift compared to traditional solutions. Its small footprint (5 mm x 5 mm housing size) integrates 10 optimized building blocks, resulting in significant space savings of 20%–50% compared to traditional 4–20 mA sensor transmitter implementations. The inclusion of an integrated high-voltage LDO and power-sequencing capability simplifies the 4–20 mA sensor transmitter's power-up. Its low current consumption for low-power operation requires only 250 µA peak current, enabling up to 50% energy savings compared to traditional solutions. The new MAX12900 solution reduces implementation complexity, generating system cost savings by converting pulse-width modulation data from a microcontroller into current in a 4-20 mA loop with two-, three-, or four-wire configurations. The MAX12900 is available in a 32-pin TQFN package and operates in a wide industrial temperature range of -40°C to +125°C.
