ADI introduces a highly integrated analog front end with a 24-bit converter core

     Analog Devices, Inc. introduced two analog front-end (AFE) devices with integrated 24-bit sigm-δ converter cores that offer the industry's best low-power, low-noise, and signal-chain integration performance. The AD7124-4 and AD7124-8 AFE connect directly to all standard industrial signal sources and sensor inputs while requiring 40% less power than comparable devices. Its best-in-class power performance is suitable for the new AFE and can be used in a range of industrial and instrumentation applications, including low-power portable devices.

     The high integration of the AD7124-4 (4 differential and 7 pseudo-differential inputs) and the AD7124-8 AFE (8 differential and 15 pseudo-differential inputs) easily and flexibly supports multiple types of sensor inputs, including resistance temperature detectors, thermocouples, voltage/current inputs, and current Bridges, simplifying the design architecture while shortening the design cycle. The new AFE has the highest system channel density in its class, allowing designers to reduce the size of the PCB or use the space saved on the same board area to expand monitoring and connection functions.

     The AD7124-4 and AD7124-8 integrate a complete signal chain, with 24-bit sigma-δ ADCs, programmable gain amplifiers (PGA), precision reference voltage sources, reference voltage buffers, current sources, temperature sensors, and excitation sources built into a single chip. The integrated diagnostic function supports SIL compatibility, reducing the need for discrete diagnostic components and saving valuable PCB area.

     The AD7124-4 and AD7124-8 offer three user-selectionable power modes that allow system designers to optimize throughput rates for desired noise performance. In the lowest power mode (255 µA), the converter has a 21.7 bit noise-free resolution at low sampling rates. User-selectable power modes allow designers of programmable logic controllers, process controllers, transmission systems, and other industrial and instrumentation equipment to develop a single platform by precisely matching the power/performance requirements of each use case.