DIGI POT 8 Click

How does it work?

DIGI POT 8 Click 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 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

Software Support

We provide a library for the DIGI POT 8 Click as well as a demo application (example), developed using MIKROE compilers. The demo can run on all the main MIKROE development boards.

Package can be downloaded/installed directly from NECTO Studio Package Manager (recommended), downloaded from our LibStock™ or found on MIKROE github account.

Library Description

This library contains API for DIGI POT 8 Click driver.

Key functions

• digipot8_write_data DIGI POT 8 write data function.

• digipot8_set_wiper_1 DIGI POT 8 set wiper 2 function.

• digipot8_set_wiper_2 DIGI POT 8 set wiper 3 function.

Example Description

This example demonstrates the use of DIGI POT 8 Click.

 void application_task ( void ) 
 { 
     for ( uint8_t cnt = DIGIPOT8_WIPER_POSITION_MIN; cnt < DIGIPOT8_WIPER_POSITION_MAX; cnt += 5 ) 
     { 
         digipot8_set_wiper_1 ( &digipot8, cnt ); 
         digipot8_set_wiper_2 ( &digipot8, cnt ); 
         digipot8_set_wiper_3 ( &digipot8, cnt ); 
         digipot8_set_wiper_4 ( &digipot8, cnt ); 
         digipot8_set_wiper_5 ( &digipot8, cnt ); 
         digipot8_set_wiper_6 ( &digipot8, cnt ); 
         log_printf( &logger, " * All wipers position set to %d *rn", ( uint16_t ) cnt ); 

         Delay_ms ( 1000 ); 
     } 
 }

The full application code, and ready to use projects can be installed directly from NECTO Studio Package Manager (recommended), downloaded from our LibStock™ or found on MIKROE github account.

Other MIKROE Libraries used in the example:

• MikroSDK.Board
• MikroSDK.Log
• Click.DIGIPOT8

Additional notes and informations

Depending on the development board you are using, you may need USB UART click, USB UART 2 Click or RS232 Click to connect to your PC, for development systems with no UART to USB interface available on the board. UART terminal is available in all MIKROE compilers.

mikroSDK

This Click board™ is supported with mikroSDK - MIKROE Software Development Kit. To ensure proper operation of mikroSDK compliant Click board™ demo applications, mikroSDK should be downloaded from the LibStock and installed for the compiler you are using.

For more information about mikroSDK, visit the official page.