DAC 4 Click carries Microchip’s MCP4728 IC, a Quad Digital-to-Analog Converter with nonvolatile (EEPROM) Memory. The digital value is converted to the appropriate voltage level in the range between GND and VCC, which is proportional to the received 12-bit number. MCP4726 also integrates EEPROM for storing DAC register and configuration bit values. These options give a lot of flexibility which make it a perfect choice for an accurate and simple generation of analog signals for various purposes, such as PLC/DCS modules, temperature and pressure control, medical and scientific instrumentation, chromatography and other similar applications, where accurate digital to analog conversion is needed.

DAC 4 Click board™ is supported by a mikroSDK compliant library, which includes functions that simplify software development.

DAC 4 Click is an advanced 12bit multichannel digital to analog converter (DAC), with 4 single-ended/pseudo differential outputs. The Click board™ has configurable internal voltage, which allows for unrestrained configuration of the device. DAC 4 Click can be used for an digital to analog conversion in various applications, such as temperature and pressure control, medical and scientific instrumentation, chromatography and other similar applications, where accurate digital to analog conversion is needed.

The main active component of the DAC 4 Click is the MCP4728, a quad, 12-bit voltage output Digital-to-Analog Convertor (DAC) with nonvolatile memory (EEPROM), from Microchip. Its on-board precision output amplifier allows it to achieve rail-to-rail analog output swing. The DAC input codes, device configuration bits, and I2C address bits are programmable to the nonvolatile memory (EEPROM) by using I2C serial interface commands. The nonvolatile memory feature enables the DAC device to hold the DAC input codes during power-off time, allowing the DAC outputs to be available immediately after power-up with the saved settings.

The MCP4728 device has a high precision internal voltage reference (VREF = 2.048V). The internal reference can be selected by user, or external reference may be used (VDD) for each channel individually. This gives the ADC 4 Click good flexibility for use in various applications.

Each channel can be operated in Normal mode or Power-Down mode individually by setting the configuration register bits. In Power-Down mode, most of the internal circuits in the powered down channel are turned off for power savings, and the output amplifier can be configured to present a known low, medium, or high resistance output load. This device also includes a Power-on Reset (POR) circuit to ensure reliable power-up and an on-board charge pump for the EEPROM programming voltage.

The MCP4728 has four output pins, which are routed to the output terminal blocks (TB1 and TB2). The output range of the DAC is 0 V to VREF or 0 V to 2×V REF. The communication with the main MCU is established over a two-wire I2C compatible serial interface, with standard (100 kHz), fast (400 kHz), or high speed (3.4 MHz) modes supported. The I2C lines (SCL and SDA) are routed to the dedicated mikroBUS™pins. The LDA pin is multipurpose GPIO: It can be used as Synchronization input or for the device I2C address selection. RDY pin can also optionaly be used to monitor status of EEPROM programming activity.

The voltage level of the logic section can be selected via the VCCSEL jumper, between 3.3V and 5V. This allows for both 3.3V and 5V capable MCUs to use the I2C communication lines properly.

• Interface: GPIO, I²C
• Compatibility: mikroBUS™
• Dimensions: 42.9 x 25.4mm
• Input Voltage: 3.3V or 5V
• Analog output voltage: Min. 0V, Max. 5V
• Settling Time: 6μs
• Sampling bit depth: 12 bits
• Operating supply voltage: Min. 2.7V, Typ. 3.3V, Max. 5.5V

• Schematic
• MCP4728 Datasheet
• mikroSDK
• GitHub