Diglient Pmod DA3 One 16-Bit D/A Output

Features and Specifications

• High resolution, 16-bit Digital-to-Analog converter
• Low noise analog output
• SMA connector
• 2.5V reference voltage
• 1.2" × 0.8" (3.0 cm × 2.0 cm) PCB size
• 6-pin Pmod connector with GPIO interface
• 3.3V Logic Level
• Follows Digilent Pmod Interface Specification Type 1

The PmodDA3 is a 16-bit digital-to-analog converter (DAC) that provides high-resolution and low-noise analog output through an SMA connector.

The PmodDA3 communicates with the host board via a SPI-like protocol. This interface is different than the traditional SPI protocol in the fact that the pin normally designated to the host receiving data (MISO), is now used for a Load DAC (LDAC) function so that the output of the DAC can be updated immediately once the module is loaded with the incoming 16 bits of data.

To send data to the Pmod, users must drive the Chip Select (CS) line to a logic level low voltage and then send the 16 clock pulses and 16 bits of data in SPI Mode 0; that is, placing the most significant bit (MSB) of data on the data line right after the Serial Clock line (SCLK) has been brought to a logic level low voltage.

When all of the data has been latched into the internal serial input register, bringing the CS line back to a logic level high voltage will transfer all of the data from the shift register to the serial input register if LDAC is at a high voltage state. Pulsing the LDAC pin low and then high will asynchronously transfer all of the data into the DAC register, resulting in the appropriate analog voltage on the SMA connector. Alternatively, users may hold the LDAC pin at a logic level low voltage when bringing the CS pin high to directly transfer the data from the shift register to the DAC register.

PmodDA3 follows Digilent's Pmod Interface Specification Type 1 (GPIO) which is used for general purpose logic. The host must provide the ability for all signals to be bi-directional logic signals. The peripheral may use any of the pins as inputs, outputs, or bi-directional. Should a PWM signal be used, it should be on pin 2.

Pmod Series Overview

The Digilent Pmod (peripheral module) Series is a small, low-cost peripheral module that can be used with a wide range of embedded systems and development boards. It is designed to extend the capabilities of embedded systems and development boards by adding new features and functionality. The Pmod communicates with host boards using 6, 8 or 12-pin connectors that can carry multiple digital control signals, taking advantage of standard serial protocols such as SPI and I²C. This allows for more effective designs by routing analog signals and power supplies only where they are needed and away from digital controller boards.

What's in the Box

• Pmod DA3
• Custom antistatic Pmod packaging