One-Chip HART Modem Saves Space, Cuts Component Count

The DS8500 is a single-chip, HART-compliant modem IC that enables the smallest solution size for modulating and demodulating 1.1-kHz/2.2-kHz FSK signals, according to the company. The device integrates an analog-to-digital converter and state machine to implement the digital filter required to eliminate noise from the HART (Highway-Addressable Remote Transducer) signal. This built-in digital filter minimizes the number of external components needed while ensuring reliable signal detection in noisy industrial environments. A simple, single-pole, lowpass/highpass RC filter is all that is required externally. Additionally, the DS8500 features a low, 285-µA (max) active-mode current for applications in which low power consumption is critical. The modem operates from 2.7 V to 3.6 V and is fully specified over the ?40°C to 85°C extended temperature range. The DS8500 comes in a lead-free, 5- by 5-mm TQFN package, making it well-suited for space-constrained, 4- to 20-mA current-loop applications. Pricing starts at $4.10 in quantities of 1000. MAXIM INTEGRATED PRODUCTS, Sunnyvale, CA. (800) 998-8800.