The AD7273/AD7274 are 10-/12-bit， high speed， low power， successive approximation ADCs， respectively. The parts operate from a single 2.35 V to 3.6 V power supply and feature throughput rates of up to 3 MSPS. Each part contains a low noise， wide bandwidth track-and-hold amplifier that can handle input frequencies in excess of 55 MHz. The conversion process and data acquisition are controlled using CS and the serial clock， allowing the devices to interface with microprocessors or DSPs. The input signal is sampled on the falling edge of CS， and the conversion is also initiated at this point. The conversion rate is determined by the SCLK. There are no pipeline delays associated with these parts. The AD7273/AD7274 use advanced design techniques to achieve very low power dissipation at high throughput rates. The reference for the parts is applied externally and can be in the range of 1.4 V to VDD. This allows the widest dynamic input range to the ADC