DIGI POT 8 Click Board™

How Does The Digi Pot 8 Click Board™ Work?

The DIGI Pot 8 Click Board™ as its foundation uses the AD5206, 6-channel 256-position digitally controlled device that performs the same electronic adjustment function as a potentiometer or variable resistor from Analog Devices. Each channel of the AD5206 contains a fixed resistor with a wiper contact that taps the fixed resistor value of 10kΩ, 50kΩ, or 100kΩ at a point determined by a digital code loaded into the SPI-compatible serial-input register. The resistance between the wiper and either endpoint of the fixed resistor varies linearly concerning the digital code transferred into the variable resistor (VR) latch. The AD5206 also has an internal Power-On preset that places the wiper in a preset midscale condition at the Power-On state.

The AD5206 communicates with MCU through the 3-Wire SPI serial interface with a maximum frequency of 10MHz. Each VR has its VR latch that holds its programmed resistance value. These VR latches are updated from an internal serial-to-parallel shift register loaded from a standard 3-wire SPI serial-input digital interface. Eleven data bits make up the data word clocked into the serial input register. The first three bits are decoded to determine which VR latch is loaded with the last eight bits of the data word when the CS pin of the SPI serial interface returns to a logic high state.

In addition to the AD5206 present on the DIGI POT 8, this Click board™ also has four 2x3 male headers. Three of them under the labels of A W and B, with also the appropriate number, represent the corresponding DIGI POT terminal of the AD5206, while the fourth header with the label VCC and GND represents an additional power supply output. Wiper terminal number 6, labeled as W6, also can be used as an auxiliary wiper output, routed to the AN pin of the mikroBUS ™ socket if the wiper back to the mikroBUS™ is required.

This Click board™ can be operated only with a 3.3V logic voltage level. The board must perform appropriate logic voltage level conversion before use with MCUs with different logic levels. However, the Click board™ comes equipped with a library containing 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 DIGI POT 8 Click corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).

Notes	Pin					Pin	Notes
Wiper OUT	AN	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	NC
Ground	GND	8	GND	GND	9	GND	Ground

ONBOARD SETTINGS AND INDICATORS

DIGI POT 8 CLICK ELECTRICAL SPECIFICATIONS