May 14, 2015 – Analog Devices, Inc. (www.analog.com, NASDAQ: ADI), a global leader in high-performance semiconductors for signal processing applications, today introduced a FET input analog front-end (AFE) with integrated A/D converter drivers designed to interface directly with current-mode sensors such as photodiodes and high-output impedance voltage sensors. The ADA4350 integrates the FET input amplifier, switching network, and A/D converter driver into a single package, simplifying design and reducing power consumption and PCB footprint by more than 50% compared to implementing multiple discrete products.

The ADA4350 maximizes the signal-to-noise ratio (SNR) of the sensor output by achieving low wideband noise performance of 90 nV/√Hz and 5 nV/√Hz at low frequencies of 10 Hz and 100 kHz, respectively. Its integrated gain switches enable it to measure small and sensitive signals, such as photons and electrons, over a wide dynamic range. The ADA4350's on-chip programmability allows designers to select optimized external feedback components. Furthermore, a single chip can convert current and voltage signals from single-ended or differential sensors into high-speed, low-noise single-ended or differential output voltages.

For analytical measurement applications, monitoring light intensity may need to be performed over decades. This requires multiple gain switching networks, which typically include multiple external amplifiers and analog switches, increasing the likelihood of system errors. The ADA4350 integrates the switching network and input amplifier to minimize leakage current, and the switching network allows for the selection of up to six externally configurable feedback networks. In test and measurement systems, a high level of measurement accuracy must be maintained across the entire gain level as the user adjusts the input range of the device. The ADA4350, with its high-impedance/low-Ib input amplifier and serial port-controlled switch network, is suitable for measuring a wider dynamic range. The ADA4350 enables a significant increase in channel count without thermal density limitations while reducing PCB footprint.