GENERAL DESCRIPTION

The AD7440/AD7450A1 are 10-bit and 12-bit high speed, low power, successive approximation (SAR) analog-to-digital converters with a fully differential analog input. These parts operate from a single 3 V or 5 V power supply and use advanced design techniques to achieve very low power dissipation at throughput rates up to 1 MSPS. The SAR architecture of these parts ensures that there are no pipeline delays.

The parts contain a low noise, wide bandwidth, differential track-and-hold amplifier (T/H) that can handle input frequencies up to 3.5 MHz. The reference voltage is applied externally to the VREF pin and can be varied from 100 mV to 3.5 V depending on the power supply and what suits the application. The value of the reference voltage determines the common-mode voltage range of the part. With this truly differential input structure and variable reference input, the user can select a variety of input ranges and bias points.

FEATURES

Fast throughput rate: 1 MSPS

Specified for VDD of 3 V and 5 V

Low power at max throughput rate

4 mW max at 1 MSPS with 3 V supplies

9.25 mW max at 1 MSPS with 5 V supplies

Fully differential analog input

Wide input bandwidth

70 dB SINAD at 100 kHz input frequency

Flexible power/serial clock speed management

No pipeline delays

High speed serial interface

SPI®/QSPI™/MICROWIRE™/DSP compatible

Power-down mode: 1 μA max

8-lead SOT-23 and MSOP packages

APPLICATIONS

Transducer interface

Battery-powered systems

Data acquisition systems

Portable instrumentation

Motor control