MCP4706A0T-E/CH

The MCP4706A0T-E/CH from Microchip Technology is a single-channel 8-bit voltage output DAC with integrated EEPROM memory for non-volatile storage of the DAC register value and configuration bits. The device supports an external VREF pin or VDD as the reference voltage, with output gain options of 1x or 2x (when using VREF). The rail-to-rail output buffer can drive loads directly without an external amplifier. The integrated EEPROM automatically recalls the last saved DAC value and configuration on power-up, enabling autonomous operation without MCU intervention. Four power-down modes reduce supply current to 60nA and configure the VOUT pin with selectable pull-down resistors (1kΩ, 125kΩ, or 640kΩ). The I2C interface supports Standard (100kHz), Fast (400kHz), and High-Speed (3.4MHz) modes with 8 possible device addresses. The A0T-E/CH suffix denotes the A0 I2C address variant, extended temperature range, SOT-23-6 package, and tube packaging.

The MCP4706A0T-E/CH uses a resistor-string DAC architecture. The 8-bit digital code selects one of 256 taps on the internal resistor divider, producing a voltage proportional to the reference voltage. When VDD is selected as the reference, the output voltage is VOUT = (D/256) × VDD, where D is the 8-bit code (0-255). When the VREF pin is used with 1x gain, VOUT = (D/256) × VREF. With 2x gain selected, VOUT = (D/256) × 2 × VREF (VREF must not exceed VDD/2). The output buffer is a rail-to-rail operational amplifier that can source and sink current while maintaining the programmed voltage. The I2C interface receives the DAC register value and configuration bits (VREF selection, gain, power-down mode) in a single write command. Writing to the DAC register updates the output immediately. The EEPROM write command saves the current DAC register and configuration to non-volatile memory; during power-up, the device automatically recalls these saved values. The power-down modes disconnect the output buffer from VOUT and connect one of three internal pull-down resistors to prevent the output from floating. The I2C address is determined by the part number suffix (A0, A1, A2, A3 variants) which maps to different address bits.

MCP4706A0T-E/CH uses the SOT-23-6 (6-lead) surface-mount package from Microchip: Pin 1 = VOUT (analog output), Pin 2 = VSS (GND), Pin 3 = VDD (supply, 2.7-5.5V), Pin 4 = SDA (I2C data), Pin 5 = SCL (I2C clock), Pin 6 = A0 (I2C address select). Pin 1 is identified by a dot on the package top. The A0 pin sets the LSB of the I2C address — tie to VDD or VSS to select one of two possible addresses. The VOUT pin can drive up to 25mA with rail-to-rail output swing. The A0T-E/CH suffix denotes: A=6-bit resolution, 0=external VREF, T=tape-and-reel, E=extended temp (-40 to +125°C), /CH=SOT-23-6 package. For 8-bit resolution, MCP4716A0 provides the same pinout; for 10-bit, MCP4725A0.

• Sensor Calibration: EEPROM stores calibration DAC value that auto-recalls on power-up, providing correct offset without MCU intervention
• Setpoint Generation: 8-bit resolution (19.5mV steps at 5V) sets comparator thresholds or voltage references
• Portable Instruments: 60nA power-down current extends battery life; EEPROM recalls last setting on wake
• Motor Control: 2x gain mode doubles a 2.5V VREF to 5V full-scale for motor speed reference
• Space-Constrained: SOT-23-6 package (3.1 x 1.8mm) fits in tiny PCB areas near the load

MCP4706A0T-E/CH is a 6-bit I2C DAC from Microchip in SOT-23-6. The MCP4716A0 provides 8-bit resolution with the same pinout. The MCP4725A0 offers 12-bit I2C DAC in SOT-23-6. The DAC60501 from TI provides 12-bit SPI DAC in SOT-23-6. The AD5601 from ADI offers 8-bit SPI DAC in SC-70-6. The MAX5216 from ADI/Maxim provides 16-bit SPI DAC in TDFN-8. The DAC439Z from TI offers quad 6-bit I2C DAC in VQFN-16 for multi-channel applications.