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The AD7303 is a dual, 8-bit voltage out DAC that operates from a single +2.7 V to +5.5 V supply. Its on-chip precision output buffers allow the DAC outputs to swing rail to rail. This device uses a versatile 3-wire serial interface that operates at clock rates up to 30 MHz, and is compatible with QSPI, SPI, microwire and digital signal processor interface standards. The serial input register is sixteen bits wide; 8 bits act as data bits for the DACs, and the remaining eight bits make up a control register.
The on-chip control register is used to address the relevant DAC, to power down the complete device or an individual DAC, to select internal or external reference and to provide a synchronous loading facility for simultaneous update of the DAC outputs with a software LDAC function.
The low power consumption of this part makes it ideally suited to portable battery operated equipment. The power consumption is 7.5 mW max at 3 V, reducing to less than 3 µW in full power-down mode.
The AD7303 is available in an 8-pin plastic dual in-line package, 8-lead SOIC and microSOIC packages.
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.
The driver contains two parts:
The Communication Driver has a standard interface, so the AD7303 driver can be used exactly as it is provided.
There are three functions which are called by the AD7303 driver:
SPI driver architecture
The following functions are implemented in this version of AD7303 driver:
Function | Description |
---|---|
char AD7303_Init(void) | Initializes the SPI communication peripheral. |
void AD7303_Write(unsigned char controlReg, unsigned char dataReg) | Sends data to AD7303. |
HW Platform(s):
This section contains a description of the steps required to run the AD7303 demonstration project on a Digilent Cerebot MX3cK platform.
Following commands were implemented in this version of AD7303 reference project for Cerebot MX3cK board.
Command | Description |
---|---|
help? | Displays all available commands. |
power= | Powers off/on the current channel. Accepted values: 0, 1. |
power? | Displays the power status. |
channel= | Selects a channel. Accepted values: 0, 1. |
channel? | Displays the current channel. |
voltage= | Sets the output voltage of the current channel. Accepted values: 0→3.3 |
voltage? | Displays last written value. |
register= | Writes to the DAC register of the current channel. Accepted values: 0 - 255. |
register? | Displays last written value. |
Commands can be executed using a serial terminal connected to the UART1 peripheral of PIC32MX320F128H.
The following image shows a list of commands in a serial terminal connected to processor’s UART peripheral.
This section presents the steps for developing a software application that will run on the Digilent Cerebot MX3cK development board for controlling and monitoring the operation of the ADI part.
This section contains a description of the steps required to run the AD7303 demonstration project on a Digilent Cerebot MC7 platform.
Following commands were implemented in this version of AD7303 reference project for Cerebot MC7 board.
Command | Description |
---|---|
help? | Displays all available commands. |
power= | Powers off/on the current channel. Accepted values: 0, 1. |
power? | Displays the power status. |
channel= | Selects a channel. Accepted values: 0, 1. |
channel? | Displays the current channel. |
voltage= | Sets the output voltage of the current channel. Accepted values: 0→3.3 |
voltage? | Displays last written value. |
register= | Writes to the DAC register of the current channel. Accepted values: 0 - 255. |
register? | Displays last written value. |
Commands can be executed using a serial terminal connected to the UART1 peripheral of dsPIC33FJ128MC706A.
The following image shows a list of commands in a serial terminal connected to processor’s UART peripheral.
This section presents the steps for developing a software application that will run on the Digilent Cerebot MC7 development board for controlling and monitoring the operation of the ADI part.
This section contains a description of the steps required to run the AD7303 Arduino demonstration project on a Digilent Cerebot MX3cK platform.
Following commands were implemented in this version of AD7303 Arduino reference project for Cerebot MX3cK board.
Command | Description |
---|---|
help? | Displays all available commands. |
power= | Powers off/on the current channel. Accepted values: 0, 1. |
power? | Displays the power status. |
channel= | Selects a channel. Accepted values: 0, 1. |
channel? | Displays the current channel. |
voltage= | Sets the output voltage of the current channel. Accepted values: 0→3.3 |
voltage? | Displays last written value. |
register= | Writes to the DAC register of the current channel. Accepted values: 0 - 255. |
register? | Displays last written value. |
Commands can be executed using the serial monitor.
Carriage return has to be selected as a line ending character. The required baud rate is 9600 baud.
The following image shows a list of commands in the serial monitor.
This section presents the steps for developing a chipKIT application that will run on the Digilent Cerebot MX3cK development board for controlling and monitoring the operation of the ADI part.