DAC 6 Click Board™

Product Code: MIKROE-4206

How Does The DAC 6 Click Board™? The DAC 6 Click Board™ is based on the DAC104S085, 10-bit resolution micro-power QUAD digital-to-analog converter with rail-to-rail output, from Texas Instruments. The DAC104S085 is manufactured on a CMOS process with an architecture that consists of switches and resistor strings that are followed by an output buffer. The reference voltage is applied at the VREFIN pin and is shared by all four DAC outputs (A, B, C, and D). This string consists of 1024 equal valued resistors with a switch at each junction of two resistors, plus a switch to the ground. The code loaded into the DAC register determines which switch is closed, connecting the proper node to the amplifier. The voltage reference pin of the DAC104S085 is not buffered, and because of that, it is recommended to drive the VREFIN pin by a voltage source with a low output impedance. This is accomplished using the MCP1501, a low drift bandgap-based voltage reference from Microchip capable of sinking and sourcing 20mA of current.

The bandgap uses chopper-based amplifiers, effectively reducing the drift to zero. The reference voltage range which can be applied to the VREFIN pin is 1V to VCC (in this case 2.048V), providing the widest possible output dynamic range with a maximum output current of 11mA per channel. The DAC 6 Click Board™ communicates with MCU using the 3-Wire SPI serial interface that is compatible with standard SPI, QSPI™, MICROWIRE™ and operates at clock rates up to 40 MHz. To use the full dynamic range of the DAC104S085, it is possible to connect the VREFIN pin to the supply voltage VCC. Because of its low power consumption, a reference source may be used as the reference input or the supply voltage which results in accuracy and stability. The reference voltage level can be selected by positioning the SMD jumper labeled as VREF SEL to an appropriate position, selecting between a value of 2.048V and the supply voltage VCC. The DAC 6 Click Board™ uses the SPI communication interface with both 3.3V and 5V. The onboard SMD jumper labeled as VCC SEL allows voltage selection for interfacing with both 3.3V and 5V MCUs. More information about the DAC104S085's functionality, electrical specifications, and typical performance can be found in the attached datasheet. However, the Click board™ comes equipped with a library that contains easy to use functions and a usage example that may be used as a reference for the development. SPECIFICATIONS Type DAC Applications Can be used in battery-operated equipment, digital gain and offset adjustment, programmable voltage and current sources, and many more. On-board modules The DAC 6 Click Board™ is based on the DAC104S085, 10-bit resolution micro-power QUAD digital-to-analog converter with rail-to-rail output, from Texas Instruments. Key Features Low power consumption, rail-to-rail voltage output, accuracy, stability, small package, and more. Interface SPI Compatibility mikroBUS Click board size S (28.6 x 25.4 mm) Input Voltage 3.3V or 5V PINOUT DIAGRAM This table shows how the pinout on the DAC 6 Click Board™ corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns). Notes Pin Pin Notes NC 1 AN PWM 16 NC NC 2 RST INT 15 NC SPI Chip Select CS 3 CS RX 14 NC SPI Clock SCK 4 SCK TX 13 NC NC 5 MISO SCL 12 NC SPI Data IN SDI 6 MOSI SDA 11 NC Power Supply 3.3V 7 3.3V 5V 10 5V Power Supply Ground GND 8 GND GND 9 GND Ground ONBOARD SETTINGS AND INDICATORS Label Name Default Description