Slider 2 Click
PID: MIKROE‐3301
Weight: 30 g
The Slider 2 click is a very accurate potentiometer Click Board, featuring a
high-quality mechanical slide-action potentiometer (slider), which in
conjunction with the accurate voltage reference IC, provides very precise
analog control voltage (CV) at its output. Featuring an accurate voltage
reference IC, the output of the Click board™ can be directly sampled by the
A/D peripheral of the microcontroller (MCU). Since there are many different
MCU architectures with different reference voltage requirements, Slider 2
click offers a possibility to select the voltage reference between 4.096V and
2.048V, two most commonly used values for different MCU peripherals.
It comes in the package which also includes the mikroSDK™ software and a
library with all the functions. The Click board™ comes as a fully tested and
approved prototype, making it a reliable device ready to use on the
development board.
The output from the potentiometer is buffered by the high-performance railto-rail operational amplifier, which ensures clean and low-noise signal to the
VO pin of the Click Board. Featuring a very accurate voltage reference and a
high-quality 30 mm slider, this Click board™ can be used in any application
that requires an analog control voltage, or it can be used to build HMI
applications, adding them an accurate slider potentiometer.
How does it work?
The Slider 2 click utilizes the PTA3043, a linear, high-grade, 10K
potentiometer made by Bourns. This potentiometer has a 30 mm travel
distance. The long travel distance of the wiper allows more accurate
movements and combined with the high-quality manufacturing process it
allows to dial-in the desired voltage with ease. This type of potentiometers
are also known as sliders, thus the name for this Click board™. The
potentiometer has a small dent in the middle, which enables tactile feedback
when the center position is reached. The potentiometer is connected
between the VREF and GND, acting as a voltage divider. Its wiper terminal
outputs voltage in the range from 0 to 4.096V, depending on its position.
The used potentiometer is linear, so the wiper potential changes linearly with
its position.
The voltage reference(VREF) is obtained from the MCP1501, a high-precision
voltage reference IC from Microchip. The main purpose of this IC is to provide
and retain a very accurate voltage of 4.096V. Its voltage reference is
accurate enough for most applications where the analog output from the
Slider 2 click can be utilized as a control voltage signal (CV). The output is
buffered with a rail-to-rail, low-power operational amplifier, labeled as
OPA344, produced by Texas Instruments. After the buffering op-amp, the
output signal is delivered at the AN pin of the mikroBUS, labeled as VO on
this Click Board, so it can be easily sampled by the internal A/D converter of
the host microcontroller unit (MCU.
Most MCUs have A/D peripherals that can use 4.096 as the reference voltage
for the full-scale value (PIC 8-bit family is a good example). However, there
are many cases where 2.048V is more adequate, so the Click board offers a
choice: if there is a HIGH logic level at the RSL pin, the N-type MOSFET will
open and another resistor will be introduced to the circuit. A voltage divider
will be formed at the input of the buffering op-amp, which will halve the
voltage from the potentiometer, reducing its maximum value to 2.048V.
When the logic level at the RSL pin is LOW, the N-type MOSFET will stay
closed, so the second resistor of the voltage divider remains isolated. This
will cause the full voltage level from the potentiometer to appear at the VO
pin of the Click Board, in the range from 0 to 4.096V max.
The MCP1501 IC has the #SHDN pin, used to shut down the IC when it's set
to a LOW logic level. When this pin is set to a LOW logic level, the voltage
reference output will be turned OFF, so there will be no voltage changes at
the VO pin. By enabling the MCP1501 the voltage reference is established
once again, so the Click Board can deliver an analog signal with the voltage
ranging from 0 to 4.096V, or from 0 to 2.048V if the RSL pin is set to a
HIGH logic level. It is recommended to start up the Click Board with the EN
pin at the LOW logic level, to allow the internal power supply of the
MCP1501 to reach its operational values.
Specifications
Type
ADC
Applications
Slider 2 click can be used in any application that requires an
analog control voltage, or it can be used to build HMI applications,
adding them an accurate slider potentiometer.
On-board
modules
PTA3043, a linear 10K potentiometer with 30 mm travel distance,
made by Bourns, Inc; MCP1501, a precise 4.096V voltage
reference, by Microchip; OPA344, a low-power rail-to-rail
operational amplifier, from Texas Instruments.
Key Features
An accurate and precise slider with long travel distance of its
wiper, a precise buffered voltage reference output which can be
directly sampled by the integrated A/D section of the
microcontroller, features a digitally selectable reference voltage
(4.096V or 2.048V) to allow compliance with different MCU
architecture.
Interface
Analog,GPIO
Input Voltage
5V
Compatibility
mikroBUS
Click board
size
M (42.9 x 25.4 mm)
Pinout diagram
This table shows how the pinout on Slider 2 Click corresponds to the pinout
on the mikroBUS™ socket (the latter shown in the two middle columns).
Notes
Analog Voltage
OUT
MCP1501 Chip
Enable
Pin
Pin
Notes
Ref. Voltage
Selection
VO
1
AN
PWM
16
RSL
NC
2
RST
INT
15
NC
EN
3
CS
RX
14
NC
Ground
NC
4
SCK
TX
13
NC
NC
5
MISO
SCL
12
NC
NC
6
MOSI
SDA
11
NC
NC
7
3.3V
5V
10
5V
GND
8
GND
GND
9
GND
Power supply
Ground
Onboard settings and indicators
Label
LD1
Name
Default
Description
PWR
-
Power LED indicator
Software support
We provide a library for the Slider 2 click on our LibStock page, as well as a
demo application (example), developed using MikroElektronika compilers. The
demo can run on all the main MikroElektronika development boards.
Library Description
The library contains functions to enable or disable the chip and sets the
maximum output voltage reference.
Key functions:
void slider2_enable(uint8_t state) - Function for enabling or disabling device
void slider2_setReference(uint8_t ref) - Function for setting max output voltage
void applicationTask()
{
sliderValue = ADC1_Read(4);
WordToHex(sliderValue, demoText);
mikrobus_logWrite(" Slider value : 0x", _LOG_TEXT);
mikrobus_logWrite(demoText, _LOG_LINE);
Delay_ms( 500 );
}
The full application code, and ready to use projects can be found on
our LibStock page.
Other mikroE Libraries used in the example:
ADC
Additional notes and information
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. The terminal
available in all MikroElektronika compilers, or any other terminal application
of your choice, can be used to read the message.
mikroSDK
This click board is supported with mikroSDK - MikroElektronika 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.
https://www.mikroe.com/slider‐2‐click/1‐9‐19