DAC 11 Click Board

How Does The DAC 11 Click Board™ Work?

The DAC 11 Click Board™ as its foundation uses the DAC128S085, a general-purpose 12-bit 8-channel digital-to-analogue converter (DAC) from Texas Instruments. The DAC128S085 is fabricated on a CMOS process with an architecture that consists of switches and resistor strings followed by an output buffer. It ensures monotonicity, low power consumption of 4.85mW at 5V, individual channel power-down capability, and has high precision output amplifier that allows rail-to-rail output swing over a wide supply voltage range.

DAC architecture consists of 4096 equal valued resistors with a switch at each junction of two resistors, plus a switch to ground. The code loaded into the DAC register determines which switch is closed, connecting the right node to the amplifier. Because all eight channels of the DAC128S085 can be controlled independently, each consists of a DAC register and a 12-bit DAC. Depending on the mode of operation, data written into a DAC register causes the 12-bit DAC output to be updated, or an additional command is required to update the DAC output. Also, a Power-On reset circuit ensures that the DAC outputs power up to zero volts and remains there until there is a valid write to the device.

The DAC 11 Click Board™ communicates with MCU using the SPI serial interface compatible with standard QSPI, MICROWIRE, and DSP interfaces, with a maximum frequency of 50 MHz. Also, this Click board™ is designed to utilize the entire dynamic range of DAC128S085 by having all power supply pins (and reference voltage pins) connected together, sharing the same supply voltage. In addition, the user is given the option of further use of the RC filter at the output to roll off output noise.

The DAC 11 Click Board™ can operate with both 3.3V and 5V logic voltage levels selected via the VCC SEL jumper. This way, it is allowed for both 3.3V and 5V capable MCUs to use the SPI communication lines properly. However, the Click board™ comes equipped with a library containing easy-to-use functions and an example code that can be used, as a reference, for further development.

Specifications

Pinout diagram

This table shows how the pinout on the DAC 11 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
SPI Data OUT	SDO	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

DAC 11 Click electrical specifications