This version is outdated by a newer approved version.DiffThis version (13 Nov 2012 15:16) was approved by Dan Nechita.The Previously approved version (28 Sep 2012 16:38) is available.Diff

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Supported Devices

Evaluation Boards

  • PmodAD6


The AD7091R is a 12-bit successive approximation analog-to-digital converter (ADC) that offers ultralow power consumption (typically 349 µA at 3 V and 1 MSPS) while achieving fast throughput rates (1 MSPS with a 50 MHz SCLK). The AD7091R uses advanced design and process techniques to achieve this very low power dissipation at high throughput rates. The part also features an on-chip, accurate 2.5 V reference.

Operating from a single 2.7 V to 5.25 V power supply, the part contains a wide bandwidth track-and-hold amplifier that can handle input frequencies in excess of 7 MHz. The AD7091R also features an on-chip conversion clock and high speed serial interface. The conversion process and data acquisition are controlled using a CONVST signal and an internal oscillator.


  • Instrumentation and Measurement
    • Battery and USB powered systems
      • Data acquisition systems
      • Handheld meters
    • Field Instruments
  • Consumer
    • Battery powered devices
  • Communications
    • Optical systems
    • Mobile communications

28 Sep 2012 15:55 · Dragos Bogdan

The goal of this project (Microcontroller No-OS) is to be able to provide reference projects for lower end processors, which can't run Linux, or aren't running a specific operating system, to help those customers using microcontrollers with ADI parts. Here you can find a generic driver which can be used as a base for any microcontroller platform and also specific drivers for different microcontroller platforms.

Driver Description

The driver contains two parts:

  • The driver for the AD7091R part, which may be used, without modifications, with any microcontroller.
  • The Communication Driver, where the specific communication functions for the desired type of processor and communication protocol have to be implemented. This driver implements the communication with the device and hides the actual details of the communication protocol to the ADI driver.

The Communication Driver has a standard interface, so the AD7091R driver can be used exactly as it is provided.

There are three functions which are called by the AD7091R driver:

  • SPI_Init() – initializes the communication peripheral.
  • SPI_Write() – writes data to the device.
  • SPI_Read() – reads data from the device.

SPI driver architecture

The following functions are implemented in this version of AD7091R driver:

Function Description
unsigned char AD7091R_Init(void) Initializes the SPI communication peripheral.
void AD7091R_SoftwareReset(void) Initiate a software reset of the device.
unsigned short AD7091R_ReadSample(void) Initiates one conversion and reads back the result.
void AD7091R_PowerDown(void) Puts the device in power-down mode.
void AD7091R_PowerUp(void) Powers up the device.
float AD7091R_ConvertToVolts(short rawSample, float vRef) Converts a 12-bit raw sample to volts.
resources/tools-software/uc-drivers/ad7091r.1352816023.txt.gz · Last modified: 13 Nov 2012 15:13 by Dan Nechita