The AD7490 is a 12-bit high speed， low power， 16-channel， successive approximation ADC. The part operates from a single 2.7 V to 5.25 V power supply and features throughput rates up to 1 MSPS. The part contains a low noise， wide bandwidth track-and-hold amplifier that can handle input frequencies in excess of 1 MHz. The conversion process and data acquisition are controlled using CS and the serial clock signal， allowing the device to easily interface with microprocessors or DSPs. The input signal is sampled on the falling edge of CS， and conversion is also initiated at this point. There are no pipeline delays associated with the part. The AD7490 uses advanced design techniques to achieve very low power dissipation at high throughput rates. For maximum throughput rates， the AD7490 consumes just 1.8 mA with 3 V supplies， and 2.5 mA with 5 V supplies. By setting the relevant bits in the control register， the analog input range for the part can be selected to be a 0 V to REFIN input or a 0 V to 2 × REFIN input， with either straight binary or twos complement output coding. The AD7490 features 16 single-ended analog inputs with a channel sequencer to allow a preprogrammed selection of channels to be converted sequentially. The conversion time is determined by the SCLK frequency because this is also used as the master clock to control the conversion. The AD7490 is available in a 32-lead LFCSP and a 28-lead TSSOP package.