DS8500

HART Modem

Fewer External Components and a Small 20-Pin TQFN Package Reduce System Cost and Size


Description

The DS8500 is a single-chip modem with Highway Addressable Remote Transducer (HART®) capabilities and satisfies the HART physical layer requirements. The device integrates the modulation and demodulation of the 1200Hz/2200Hz FSK signal, has very low power consumption, and needs only a few external components due to the integrated digital signal processing. The input signal is sampled by an analog-to-digital converter (ADC), followed by a digital filter/demodulator. This architecture ensures reliable signal detection in noisy environments. The output digital-to-analog converter (DAC) generates a sine wave and provides a clean signal with phase-continuous switching between 1200Hz and 2200Hz. Low power is achieved by disabling the receive circuits during transmit and vice versa. The DS8500 is ideal for low-power process control transmitters.
DS8500: Typical Application Circuit DS8500: Typical Application Circuit Enlarge++

Key Features

  • Single-Chip, Half-Duplex, 1200bps FSK Modulation and Demodulation
  • Digital Signal Processing Provides Reliable Input Signal Detection in Noisy Conditions
  • Sinusoidal Output Signal with Lowest Harmonic Distortion
  • Few External Components Enable a Space-Saving Solution
  • Standard Component 3.6864MHz Crystal
  • Complies to HART Physical Layer Requirements
  • 2.7V to 3.6V Operating Voltage
  • 285µA (max) Current Consumption
  • Space-Saving, 5mm x 5mm x 0.8mm, 20-Pin TQFN Package

Applications/Uses

  • 4-20mA Loop-Powered Transmitters for Temperature, Pressure, Flow, and Level Measurement
  • HART Modem Interface Connectivity
  • HART Multiplexers

DS8500-KIT:  Evaluation Kit for the DS8500
 

Related Resources

Type ID Title
Evaluation Board7196DS8500-KIT Evaluation Kit for the DS8500