Create the ultimate solution for signal magnification with MCP6S21 and PIC18F57Q43

Amplify with precision

GainAMP 2 click with Curiosity Nano with PIC18F57Q43

Published Feb 13, 2024

Click board™

GainAMP 2 click

Dev. board

Curiosity Nano with PIC18F57Q43

Compiler

NECTO Studio

MCU

PIC18F57Q43

Whether you're working with audio, sensor data, or other low-level signals, our 6-channel programmable gain amplifier is an ideal solution for boosting and optimizing signal quality

Hardware Overview

How does it work?

GainAMP 2 Click is based on the MCP6S21, a rail-to-rail I/O, low noise programmable gain amplifier (PGA) from Microchip. This integrated circuit features six multiplexed non-inverting inputs, with a gain that can be programmed via the SPI interface for each input individually. The channels CH0 to CH5 are the six input channels connected to the external signal sources. The internal multiplexer selects the channel that is gained and sent to the output pin. The gain stage of the MCP6S21 has eight different discrete steps of gain: 1, 2, 4, 5, 8, 10, 16, and 32V/V. The rail-to-rail inputs and outputs accept voltage levels up to VCC with no distortions or phase shifting. The output voltage is offset by the resistor ladder network on

the output stage and the voltage on the voltage reference pin. Besides the VOUT pin on the ten-pole I/O connector, the MCP6S21 output pin is also routed to the AN pin of the mikroBUS™ so it can be used as the input signal for the ADC. This allows the amplified signal to be easily digitalized and processed by the MCU. Using the click board in this configuration effectively turns the GainAMP 2 click into an analog port expander with the selectable gain on its inputs. The MCP6S21 device can be put in a shutdown mode by setting the appropriate bits of the internal register via the SPI interface. While in shutdown mode, the power consumption is minimal. The device stays in Shutdown mode until a valid command is received

via the SPI. While in the shutdown mode, the device remembers the states of the internal registers, so when it awakens, it will resume working as before. The internal registers can be easily accessed by using MIKROE library functions. More information about the registers and their settings can be found in the MCP6S21 datasheet. This Click board™ can operate with either 3.3V or 5V logic voltage levels selected via the VCC SEL jumper. This way, both 3.3V and 5V capable MCUs can use the 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.

Features overview

Development board

PIC18F57Q43 Curiosity Nano evaluation kit is a cutting-edge hardware platform designed to evaluate microcontrollers within the PIC18-Q43 family. Central to its design is the inclusion of the powerful PIC18F57Q43 microcontroller (MCU), offering advanced functionalities and robust performance. Key features of this evaluation kit include a yellow user LED and a responsive

mechanical user switch, providing seamless interaction and testing. The provision for a 32.768kHz crystal footprint ensures precision timing capabilities. With an onboard debugger boasting a green power and status LED, programming and debugging become intuitive and efficient. Further enhancing its utility is the Virtual serial port (CDC) and a debug GPIO channel (DGI

GPIO), offering extensive connectivity options. Powered via USB, this kit boasts an adjustable target voltage feature facilitated by the MIC5353 LDO regulator, ensuring stable operation with an output voltage ranging from 1.8V to 5.1V, with a maximum output current of 500mA, subject to ambient temperature and voltage constraints.

PIC18F57Q43 Curiosity Nano double side image

Microcontroller Overview

MCU Card / MCU

Architecture

PIC

MCU Memory (KB)

128

Silicon Vendor

Microchip

Pin count

RAM (Bytes)

8196

You complete me!

Accessories

Curiosity Nano Base for Click boards is a versatile hardware extension platform created to streamline the integration between Curiosity Nano kits and extension boards, tailored explicitly for the mikroBUS™-standardized Click boards and Xplained Pro extension boards. This innovative base board (shield) offers seamless connectivity and expansion possibilities, simplifying experimentation and development. Key features include USB power compatibility from the Curiosity Nano kit, alongside an alternative external power input option for enhanced flexibility. The onboard Li-Ion/LiPo charger and management circuit ensure smooth operation for battery-powered applications, simplifying usage and management. Moreover, the base incorporates a fixed 3.3V PSU dedicated to target and mikroBUS™ power rails, alongside a fixed 5.0V boost converter catering to 5V power rails of mikroBUS™ sockets, providing stable power delivery for various connected devices.

Used MCU Pins

mikroBUS™ mapper

Signal Output

PA0

RST

SPI Chip Select

PD4

SPI Clock

PC6

SCK

SPI Slave Data OUT

PC5

MISO

SPI Slave Data IN

PC4

MOSI

Power Supply

3.3V

Ground

GND

PWM

INT

SCL

SDA

Power Supply

Ground

GND

Take a closer look

Click board™ Schematic

Step by step

Project assembly

Curiosity Nano Base for Click boards front image hardware assembly

Start by selecting your development board and Click board™. Begin with the Curiosity Nano with PIC18F57Q43 as your development board.

Charger 27 Click front image hardware assembly

PIC18F47Q10 Curiosity Nano front image hardware assembly

Charger 27 Click complete accessories setup image hardware assembly

Board mapper by product8 hardware assembly

PIC18F57Q43 Curiosity MCU Step hardware assembly

Necto No Display image step 8 hardware assembly

Debug Image Necto Step hardware assembly

Track your results in real time

Application Output

1. Application Output - In Debug mode, the 'Application Output' window enables real-time data monitoring, offering direct insight into execution results. Ensure proper data display by configuring the environment correctly using the provided tutorial.

2. UART Terminal - Use the UART Terminal to monitor data transmission via a USB to UART converter, allowing direct communication between the Click board™ and your development system. Configure the baud rate and other serial settings according to your project's requirements to ensure proper functionality. For step-by-step setup instructions, refer to the provided tutorial.

3. Plot Output - The Plot feature offers a powerful way to visualize real-time sensor data, enabling trend analysis, debugging, and comparison of multiple data points. To set it up correctly, follow the provided tutorial, which includes a step-by-step example of using the Plot feature to display Click board™ readings. To use the Plot feature in your code, use the function: plot(*insert_graph_name*, variable_name);. This is a general format, and it is up to the user to replace 'insert_graph_name' with the actual graph name and 'variable_name' with the parameter to be displayed.

Software Support

Library Description

This library contains API for GainAMP 2 Click driver.

Key functions:

gainamp2_set_channel_gain - Set the channel gain
gainamp2_get_voltage - Return voltage measured from VOUT pin
gainamp2_write_Command - Send Command

Open Source

Code example

The complete application code and a ready-to-use project are available through the NECTO Studio Package Manager for direct installation in the NECTO Studio. The application code can also be found on the MIKROE GitHub account.

/*!
 * \file 
 * \brief GainAmp2 Click example
 * 
 * # Description
 * This application is programmable gain amplifier
 *
 * The demo application is composed of two sections :
 * 
 * ## Application Init 
 * Initializes and sets GainAMP 2 Click channel 0 to amplify the signal 2 times
 * 
 * ## Application Task  
 * Displays the voltage measured from VOUT pin
 * 
 * \author MikroE Team
 *
 */
// ------------------------------------------------------------------- INCLUDES

#include "board.h"
#include "log.h"
#include "gainamp2.h"

// ------------------------------------------------------------------ VARIABLES

static gainamp2_t gainamp2;
static log_t logger;

// ------------------------------------------------------ APPLICATION FUNCTIONS

void application_init ( void )
{
    log_cfg_t log_cfg;
    gainamp2_cfg_t cfg;

    /** 
     * Logger initialization.
     * Default baud rate: 115200
     * Default log level: LOG_LEVEL_DEBUG
     * @note If USB_UART_RX and USB_UART_TX 
     * are defined as HAL_PIN_NC, you will 
     * need to define them manually for log to work. 
     * See @b LOG_MAP_USB_UART macro definition for detailed explanation.
     */
    LOG_MAP_USB_UART( log_cfg );
    log_init( &logger, &log_cfg );
    log_info( &logger, "---- Application Init ----" );

    //  Click initialization.

    gainamp2_cfg_setup( &cfg );
    GAINAMP2_MAP_MIKROBUS( cfg, MIKROBUS_1 );
    gainamp2_init( &gainamp2, &cfg );
    
    gainamp2_set_channel_gain ( &gainamp2, GAINAMP2_CH0, GAINAMP2_GAIN_2X );
    log_printf( &logger,"Channel 0 - aplified 2x \r\n" ); 
}

void application_task( void )
{
    log_printf( &logger,"Voltage at VOUT: %f \r\n", gainamp2_get_voltage( &gainamp2 ) );
    log_printf( &logger,"------------------------------- \r\n " );
    Delay_ms ( 1000 );
}

int main ( void ) 
{
    /* Do not remove this line or clock might not be set correctly. */
    #ifdef PREINIT_SUPPORTED
    preinit();
    #endif
    
    application_init( );
    
    for ( ; ; ) 
    {
        application_task( );
    }

    return 0;
}

// ------------------------------------------------------------------------ END