Achieve incredible success in analog multiplexing with CD74HC4067 and PIC18F57Q43

The ultimate analog switching solution

Analog MUX Click with Curiosity Nano with PIC18F57Q43

Published Feb 13, 2024

Click board™

Analog MUX Click

Dev. board

Curiosity Nano with PIC18F57Q43

Compiler

NECTO Studio

MCU

PIC18F57Q43

Achieve precise control over analog signals in complex systems with our 16-channel input switching solution optimized for high-performance applications in various industries

Hardware Overview

How does it work?

Analog MUX Click is based on the CD74HC4067, a high-speed CMOS logic 16-channel analog multiplexer/demultiplexer from Texas Instruments. It supports 3.3V and 5V power supplies, as well as rail-to-rail operation, allowing it to be used in various applications. Four control pins switch one of sixteen inputs to a single output. Control pins labeled as S0, S1, S2, and S3 are routed to the mikroBUS™ and can be operated by both 3.3V and 5V MCUs. These pins are routed to the RST, PWM, INT, and CS pins of the mikroBUS™, respectively, while the common output pin from the multiplexer is routed to the AN pin on the mikroBUS™. The CD74HC4067 IC is digitally controlled analog switch that utilize silicon-gate CMOS technology to achieve operating speeds similar to LSTTL, with the low power

consumption of standard CMOS integrated circuits. The mentioned analog multiplexer/demultiplexer control analog voltages that may vary across the voltage supply range. The ultra-low leakage current ensures that there is no signal interference from the inputs that are not selected by the S0, S1, S2, and S3 pins. A low crosstalk also ensures that the signal on one channel remains clean of interferences caused by other channels. To prevent any two inputs to be switched at the output at the same time, a break-before-make switching action is utilized. This ensures a reliable operation of the IC and the Click board™ itself. Analog MUX click is bidirectional switch as well, thus allowing any analog input to be used as an output and vice-versa. The switches have low “on” resistance and low “off” leakages.

All of the input channels can be easily connected to the two 9 pole spring action block terminals, without having to use any additional tools, such as screwdrivers. More information about the CD74HC4067 can be found in the attached datasheet. However, the Click board™ comes equipped with a library that contains easy to use functions and a usage example that may be used as a reference for the development. 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. Also, this 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

Common Output

PA0

Control pin 0

PA7

RST

Control pin 3

PD4

SCK

MISO

MOSI

Power Supply

3.3V

Ground

GND

Control pin 1

PB0

PWM

Control pin 2

PA6

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

Software Support

Library Description

This library contains API for Analog MUX Click driver.

Key functions:

analogmux_get_voltage - Generic read voltage function
analogmux_set_channel - This function sets the active channel on the MUX.

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 AnalogMUX Click example
 * 
 * # Description
 * This example showcases how to initialize, configure and use the Analog MUX Click module. 
 * The Click switches one of the 16 inputs to output so the adc value of that input 
 * can be read on the COM (AN) pin. The RST, PWM, CS and INT are used as control output pins. 
 *
 * The demo application is composed of two sections :
 * 
 * ## Application Init 
 * This function initializes and configures the logger and Click modules.
 * 
 * ## Application Task  
 * This function reads ADC value and voltage from channel 0 (AN0) and shows the results 
 * on the USB UART every 2 seconds. 
 * 
 * \author MikroE Team
 *
 */
// ------------------------------------------------------------------- INCLUDES

#include "board.h"
#include "log.h"
#include "analogmux.h"

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

static analogmux_t analogmux;
static log_t logger;

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

void application_init ( void )
{
    log_cfg_t log_cfg;
    analogmux_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 );
    Delay_100ms( );
    log_info( &logger, "---- Application Init ----" );

    //  Click initialization.

    analogmux_cfg_setup( &cfg );
    ANALOGMUX_MAP_MIKROBUS( cfg, MIKROBUS_1 );
    analogmux_init( &analogmux, &cfg );

    analogmux_set_channel( &analogmux, ANALOGMUX_CHANNEL_0 );
    log_printf( &logger, " Channel 0 enabled\r\n" );
    log_printf( &logger, " -------------------\r\n" );
}

void application_task ( void )
{
    uint16_t tmp;
    float val;

    tmp = analogmux_generic_read( &analogmux );
    
    log_printf( &logger, " ADC value : %u\r\n", tmp );

    val = analogmux_generic_read_voltage( &analogmux );

    log_printf( &logger, " Voltage: %.3f mV\r\n", val );
    log_printf( &logger, " -------------------\r\n" );

    Delay_ms ( 1000 );
    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