Fast SAR ADC serves instrumentation, communications, and medical applications
AUGUST 3--Analog Devices Inc. (Wilmington, MA; products.analog.com/products/info.asp?product=AD7484) has announced the availability of the AD7484, reportedly the fastest 14-bit SAR (successive approximation register) ADC available.
AUGUST 3--Analog Devices Inc. (Wilmington, MA; products.analog.com/products/info.asp?product=AD7484) has announced the availability of the AD7484, reportedly the fastest 14-bit SAR (successive approximation register) ADC available; it offers a parallel interface with throughput rates up to 3 Msamples/s. A 12-bit version--the AD7482--is also available. Interfacing is via standard control lines, making the converters directly compatible with microcontrollers and digital-signal processors. These ADCs contain a low-noise, wide-bandwidth track/hold amplifier that can handle input frequencies in excess of 50 MHz. Factory trimming ensures high dc accuracy resulting in very low INL, offset, and gain errors. The converters use advanced circuit-design techniques to achieve very low power dissipation (80 mW) at a high throughput rate of 3 Msamples/s.
There are two power-saving modes. NAP mode keeps reference circuitry active for quick power up and consumes 5 mW. STANDBY mode reduces power consumption to a mere 5 uW. The AD7484 features an on-board +2.5-V reference and accommodates an external +2.5-V reference source. If the analog input range strays outside the nominal voltage or drops to as low as 200 mV below ground, the designer can still accurately resolve the signal.
Applications include precision data-acquisition modules and process-control subsystems, medical instrumentation, wired communications (optical-fiber EDFA, MEMS-based switching), spectrum analyzers, and a wide range of high-speed, high-accuracy applications requiring functionally complete performance in a small footprint.