Arduino driver for the Microchip MCP4728 4-channel 12-bit DAC.

The MCP4728 provides four independent high-resolution analog voltage outputs using a digital I²C interface, making it ideal for multi-channel signal generation, calibration, waveform synthesis, and analog control systems.

• 4-channel 12-bit DAC (0–4095 per channel)

• Fast write (simultaneous update of all channels)

• EEPROM write support (non-volatile storage)

• Individual channel configuration (VREF, Gain, Power-down)

• Sequential and multi-write modes

• Readback of DAC and EEPROM values

The MCP4728 communicates using I²C interface.

• Default I²C address: 0x60

• Supported bus speeds:

  • 100 kHz
  • 400 kHz (recommended)

• Arduino Library Manager

  1. Open Arduino IDE
  2. Go to Library Manager
  3. Search for 7Semi MCP4728
  4. Click Install

• Manual Installation

  1. Download this repository as ZIP
  2. Arduino IDE → Sketch → Include Library → Add .ZIP Library

dac.begin(0x60);

• Initializes MCP4728 with default I²C settings

dac.analogWrite(DAC_A, 2048);

• Writes value to one channel (no EEPROM)
• Range: 0 → 4095

uint16_t values[4] = {1000, 2000, 3000, 4000};
dac.fastWrite(values);

• Updates all 4 channels simultaneously
• No EEPROM write → fast operation

dac.multiWrite(values, true);

• false → DAC only (fast)
• true → DAC + EEPROM (persistent)

uint16_t values[4] = {1000, 2000, 3000, 4000};
dac.sequentialWrite(1, values, 3);

• Writes starting from channel index
• Supports partial updates

dac.setGain(GAIN_1X, GAIN_1X, GAIN_2X, GAIN_2X);

• 0 → Gain x1
• 1 → Gain x2

dac.setVref(VREF_EXTERNAL, VREF_EXTERNAL, VREF_2_048V, VREF_2_048V);

• 0 → VDD reference
• 1 → Internal 2.048V reference

dac.powerDown(PWR_NORMAL, PWR_1KOHM, PWR_100KOHM, PWR_500KOHM);

• 0 → Normal operation
• 1 → 1kΩ pull-down
• 2 → 100kΩ pull-down
• 3 → 500kΩ pull-down

uint16_t values[4];
dac.readDAC(values);

• Reads current DAC output values

uint16_t dacVals[4];
uint16_t eepromVals[4];
uint8_t status;

dac.readAll(dacVals, eepromVals, status);

Notes:

• DAC resolution = 12-bit (0–4095)
• Output voltage depends on:
  • VREF selection
  • Gain setting
• Avoid frequent EEPROM writes (limited write cycles)
• Use fastWrite() for real-time applications

• Multi-channel waveform generation
• Analog control systems
• Sensor calibration
• Signal synthesis (sine, ramp, etc.)