The AD5668 device is a low power, octal, 16-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 AD5668 has an on-chip reference with an internal gain of 2. The AD5668-1 has an 1.25 V 5 ppm/°C reference, giving a full-scale output range of 2.5 V; the AD5668-2, -3 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 (AD5668-1, -2) or midscale (AD5668-3) 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 AD5668 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.
The AD5668-EP supports defense and aerospace applicatons (AQEC)
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 Renesas platforms.
The driver contains two parts:
The Communication Driver has a standard interface, so the AD5668 driver can be used exactly as it is provided. There are three functions which are called by the AD5668 driver:
The implementation of these three functions depends on the used microcontroller.
The following functions are implemented in this version of AD5668 driver:
|unsigned char AD5668_Init(void)||Initializes the SPI communication peripheral.|
|void AD5668_SetRegisterValue(unsigned short regValue)||Writes to the DAC register.|
This section contains a description of the steps required to run the AD5668 demonstration project on a Renesas RL78G13 platform.
An EVAL-AD5668EBZ has to be interfaced with the Renesas Demonstration Kit (RDK) for RL78G13:
EVAL-AD5668SDZ connector J5 SYNC → YRDKRL78G13 J11 connector Pin 1 EVAL-AD5668SDZ connector J7 DIN → YRDKRL78G13 J11 connector Pin 2 EVAL-AD5668SDZ connector J6 SCLK → YRDKRL78G13 J11 connector Pin 4
With the Applilet3 for RL78G13 tool the following peripherals have to be configured:
Choose to generate the Transmit/receive function for the CSI10 and configure the interface with the following settings:
Configure TM00 as an interval timer:
Disable the watchdog timer:
This section presents the steps for developing a software application that will run on the Renesas Demo Kit for RL78G13 for controlling and monitoring the operation of the ADI part.
Two software applications have to be used: Applilet3 for RL78G13 (a tool that automatically generates device drivers for MCU peripheral functions) and IAR Embedded Workbench for Renesas RL78 (the integrated development environment).
This section contains a description of the steps required to run the AD5668 demonstration project on a Renesas RX62N platform.
An EVAL-AD5668SDZ board has to be interfaced with the Renesas Demonstration Kit (RDK) for RX62N:
EVAL-AD5668SDZ connector J7 DIN → YRDKRX62N J8 connector Pin 19 EVAL-AD5668SDZ connector J6 SCLK → YRDKRX62N J8 connector Pin 20 EVAL-AD5668SDZ connector J5 SYNC → YRDKRX62N J8 connector Pin 15
This section presents the steps for developing a software application that will run on the Renesas Demo Kit for RX62N for controlling and monitoring the operation of the ADI part.