This version (05 Feb 2014 19:00) was approved by Lars-Peter Clausen.The Previously approved version (06 Nov 2012 17:10) is available.
Table of Contents
Supported Devices
Evaluation Boards
Overview
The AD5628 device is a low power, octal, 12-bit, buffered voltage-output DAC. The device operates from a single 2.7 V to 5.5 V supply and is guaranteed monotonic by design. The AD5628 is available in both a 4 mm × 4 mm LFCSP and a 16-lead TSSOP.
The AD5628 has an on-chip reference with an internal gain of 2. The AD5628-1 has an 1.25 V 5 ppm/°C reference, giving a full-scale output range of 2.5 V; the AD5628-2, has a 2.5 V 5 ppm/°C reference, giving a full-scale output range of 5 V. The on-board reference is off, at power-up, allowing the use of an external reference. The internal reference is enabled via a software write.
The part incorporates a power-on reset circuit that ensures that the DAC output powers up to 0 V and remains powered up at this level until a valid write takes place. The part contains a power-down feature that reduces the current consumption of the device to 400 nA at 5 V and provides software-selectable output loads while in power-down mode for any or all DAC channels.
The outputs of all DACs can be updated simultaneously using the LDAC function, with the added functionality of user-selectable DAC channels to simultaneously update. There is also an asynchronous CLR that updates all DACs to a user-programmable code—zero scale, midscale, or full scale.
The AD5628 utilizes a versatile 3-wire serial interface that operates at clock rates of up to 50 MHz and is compatible with standard SPI®, QSPI™, MICROWIRE™, and DSP interface standards. The on-chip precision output amplifier enables rail-to-rail output swing.
Applications
- Process control
- Portable battery-powered instruments
- Digital gain and offset adjustment
- Programmable voltage and current sources
- Programmable attenuators
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 AD5628 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 AD5628 driver can be used exactly as it is provided.
There are three functions which are called by the AD5628 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 AD5628 driver:
| Function | Description |
|---|---|
| char AD5628_Init(void) | Resets the device and performs several initializations. |
| void AD5628_PowerMode(unsigned char pwrMode, unsigned char channel) | Sets the device in a specific power mode. |
| void AD5628_Reset(void) | Resets the device. |
| void AD5628_SetInputRegister(unsigned long registerValue) | Writes a 32-bit data-word to the Input Register of the device. |
resources/tools-software/uc-drivers/ad5628.txt · Last modified: 23 Jul 2013 15:46 by Lucian Sin