with Temperature Sensor

Preliminary Technical Data

AD7291

Rev. PrC

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FEATURES

12 bit SAR ADC

8 single-ended inputs

Channel sequencer functionality

Analog Input Range 0 to 2.5V

12-bit temperature-to-digital converter

Temperature sensor accuracy of ±2°C typical

Temperature range: −40°C to +125°C

Specified for V

Logic Voltage V

Power-down current : <10 µA

Internal 2.5V Reference

standard & fast modes

20-lead LFCSP

Functional Block Diagram

Figure 1.

GENERAL DESCRIPTION

The AD7291 is a 12-bit, high speed, low power, 8-channel,

successive approximation ADC with an internal temperature

sensor. The part operates from a single 3.3V power supply and

amplifier which can handle input frequencies of up to 70MHz,

and a multiplexer allows samples from eight channels.

Each AD7291 provides a 2-wire serial interface compatible with

which enables the selection of a pre-programmable sequence of

channels for conversion. The device has an on-chip 2.5 V

reference that can be disabled to allow the use of an external

reference.

The AD7291 includes a high accuracy band-gap temperature

sensor, which is monitored and digitized by the12-bit ADC to

give a resolution of 0.25°C. The AD7291 uses advanced design

techniques to achieve very low power dissipation at high

throughput rates. The part also offers flexible

power/throughput rate management options and is offered in a

20 lead LFCSP package

PRODUCT HIGHLIGHTS

1. Ideally suited to monitoring system variables in a variety of

systems including telecommunications, process and

industrial control

3. Eight Single-Ended Inputs with a Channel Sequencer.

A consecutive sequence of channels can be selected on

which the ADC cycles and converts.

4. Integrated temperature sensor with 0.25°C resolution.

Table 1. AD7298 and Related Products

Device

Resolution

Interface

Features

AD7298

12-Bit

SPI

8 Channel ADC & Temp Sensor

AD7291

12-Bit

8 Channel ADC & Temp Sensor