The AD5700/AD5700-1 are single-chip solutions, designed and specified to operate as a HART® FSK half-duplex modem, complying with the HART physical layer requirements. The AD5700/AD5700-1 integrate all of the necessary filtering, signal detection, modulating, demodulating and signal generation functions, thus requiring few external components. The 0.5% precision internal oscillator on the AD5700-1 greatly reduces the board space requirements, making it ideal for line-powered applications in both master and slave configurations. The maxi- mum supply current consumption is 115 μA, making the AD5700/ AD5700-1 an optimal choice for low power loop-powered applica- tions. Transmit waveforms are phase continuous 1200 Hz and 2200 Hz sinusoids. The AD5700/AD5700-1 contain accurate carrier detect circuitry and use a standard UART interface.