Analog Devices introduced a dc-coupled VGA (variable-gain amplifier) that supports an extended industrial temperature range of –55 degrees C to 125 degrees C and a power supply range from +/–3 V to +/–12 V .

The AD8336 includes a voltage feedback op-amp at its input that allows the gain to be externally adjusted. The nominal preamp gain is 4× (12 dB); a gain of 20× (26 dB) can be obtained at a reduced bandwidth. The AD8336 operates at a maximum gain range of 0 dB to 60 dB with the preamp gain set to 26 dB. The low input refered noise of 3.2 nV/root-Hz allows the VGA to process very small signals while the large usable supplies expand the dynamic range by a factor of four (12 dB) from +/–3 V to +/–12 V, since the noise level stays the same for all supplies.

The AD8336 features low power of 150 mW at a +/–3 V supply, low noise of 3.2 nV/ root-Hz, low output offset of less than 50 mV at maximum gain and a slew rate of 450 V/microsecond for a 2-V step. The inclusion of a voltage feedback op-amp at its input allows the AD8336 to accommodate both inverting and non-inverting topologies, and thereby, a dual polarity VGA. The preamp gain can be set from 12 dB to 26 dB.

The AD8336 is sampling now and available in a 4 mm x 4 mm, 16-lead LFCSP (lead-frame chip-scale package) and will be available in volume production in October 2006. The VGA is priced at $4.59 in 1,000-piece quantities.