Temperature Meter using LM35 Analog Sensor and Arduino Nano LCD Shield

Another project which display the ambient temperature on 16X2 LCD, Project is based on compact multipurpose Arduino Nano LCD shield and LM35 analog temperature sensor, shield also provided with 3 Tactile Switches, Relay, Power MOSFET, Trimmer Potentio-meter to create multi projects. Circuit works with 5V DC, can be power up from USB or separate header connector.  

Download PDF Document

Download Arduino Code for LCD Based Temperature Meter

Arduino Pins LCD

  • LCD RS pin to digital pin 12
  • LCD Enable pin to digital pin 11
  • LCD D4 pin to digital pin 5
  • LCD D5 pin to digital pin 4
  • LCD D6 pin to digital pin 3
  • LCD D7 pin to digital pin 2
  • LCD R/W pin to ground

Arduino Pins Various Devices

  • Switch 1 Arduino Pin A3
  • Switch 2 Arduino Pin D6
  • Switch 3 Arduino Pin D7
  • Current Sensor ACS714 Arduino Pin A5
  • Trimmer Potentio-Meter Arduino Pin A0
  • LM35 Sensor Arduino Pin A4
  • Power MOSFET Arduino Pin D9
  • Relay Arduino Pin D8

The LM35 series are precision integrated-circuit temperature devices with an output voltage linearly-proportional to the Centigrade temperature. The LM35 device has an advantage over linear temperature sensors calibrated in Kelvin, as the user is not required to subtract a large constant voltage from the output to obtain convenient Centigrade scaling. The LM35 device does not require any external calibration or trimming to provide typical accuracies of ±¼°C at room temperature and ±¾°C over a full −55°C to 150°C temperature range. Lower cost is assured by trimming and calibration at the wafer level. The low-output impedance, linear output, and precise inherent calibration of the LM35 device makes interfacing to readout or control circuitry especially easy. The device is used with single power supplies, or with plus and minus supplies. As the LM35 device draws only 60 µA from the supply, it has very low self-heating of less than 0.1°C in still air. The LM35 device is rated to operate over a −55°C to 150°C temperature range, while the LM35C device is rated for a −40°C to 110°C range (−10° with improved accuracy). The LM35-series devices are available packaged in hermetic TO transistor packages, while the LM35C, LM35CA, and LM35D devices are available in the plastic TO-92 transistor package.

LM35 Features
Calibrated Directly in Celsius (Centigrade)
Linear + 10-mV/°C Scale Factor
0.5°C Ensured Accuracy (at 25°C)
Rated for Full −55°C to 150°C Range
Suitable for Remote Applications
Low-Cost Due to Wafer-Level Trimming
Operates From 4 V to 30 V
Less Than 60-µA Current Drain
Low Self-Heating, 0.08°C in Still Air
Non-Linearity Only ±¼°C Typical
Low-Impedance Output, 0.1 Ω for 1-mA Load

Arduino Code


#include<LiquidCrystal.h>

LiquidCrystal lcd(12,11,5,4,3,2);
const int inPin = A4;
void setup()
{
lcd.begin(16,2);
}
void loop()
{
int value = analogRead(inPin);
lcd.setCursor(0,1);
float millivolts = (value / 1023.0) * 5000;
float celsius = millivolts / 10;
lcd.clear();
lcd.setCursor(0,0);
lcd.print(celsius);
lcd.print(“C”);
lcd.setCursor(0,1);
lcd.print((celsius * 9)/5 + 32);
lcd.print(“F”);
delay(1000);
}

Multipurpose Compact 16X2 LCD Shield For Arduino Nano

Compact multipurpose Arduino Nano 16X2 LCD shield can be used to develop various projects, shield provided with various things, LM 35 Temperature sensor, 3X Tactile Switch, Vertical Trimmer Potentiometer, 12V Relay with NO/NC output, power MOSFET, AC714 current sensor and 16X2 LCD.

Arduino Pins LCD

  • LCD RS pin to digital pin 12
  • LCD Enable pin to digital pin 11
  • LCD D4 pin to digital pin 5
  • LCD D5 pin to digital pin 4
  • LCD D6 pin to digital pin 3
  • LCD D7 pin to digital pin 2
  • LCD R/W pin to ground

Arduino Pins Various Devices

  • Switch 1 Arduino Pin A3
  • Switch 2 Arduino Pin D6
  • Switch 3 Arduino Pin D7
  • Current Sensor ACS714 Arduino Pin A5
  • Trimmer Potentiometer Arduino Pin A0
  • LM35 Sensor Arduino Pin A4
  • Power MOSFET Arduino Pin D9
  • Relay Arduino Pin D8

Arduino Code for 16X2 LCD


/*
LiquidCrystal Library – display() and noDisplay()

Demonstrates the use a 16×2 LCD display. The LiquidCrystal
library works with all LCD displays that are compatible with the
Hitachi HD44780 driver. There are many of them out there, and you
can usually tell them by the 16-pin interface.

This sketch prints “Hello World!” to the LCD and uses the
display() and noDisplay() functions to turn on and off
the display.

The circuit:
* LCD RS pin to digital pin 12
* LCD Enable pin to digital pin 11
* LCD D4 pin to digital pin 5
* LCD D5 pin to digital pin 4
* LCD D6 pin to digital pin 3
* LCD D7 pin to digital pin 2
* LCD R/W pin to ground
* 10K resistor:
* ends to +5V and ground
* wiper to LCD VO pin (pin 3)

Library originally added 18 Apr 2008
by David A. Mellis
library modified 5 Jul 2009
by Limor Fried (http://www.ladyada.net)
example added 9 Jul 2009
by Tom Igoe
modified 22 Nov 2010
by Tom Igoe
modified 7 Nov 2016
by Arturo Guadalupi

This example code is in the public domain.

http://www.twovolt.com

*/

// include the library code:
#include <LiquidCrystal.h>

// initialize the library by associating any needed LCD interface pin
// with the arduino pin number it is connected to
const int rs = 12, en = 11, d4 = 5, d5 = 4, d6 = 3, d7 = 2;
LiquidCrystal lcd(rs, en, d4, d5, d6, d7);

void setup() {
// set up the LCD’s number of columns and rows:
lcd.begin(16, 2);
// Print a message to the LCD.
lcd.print(“hello, world!”);
}

void loop() {
// Turn off the display:
lcd.noDisplay();
delay(500);
// Turn on the display:
lcd.display();
delay(500);
}

10 LED Bar-Graph Display- 10 Segment Bar-Graph Voltmeter Arduino Nano

Turns on a series of 10 Segments of LEDs based on the value of an analog sensor. This is a simple way to make a bar graph display. This method can be used to control any series of digital outputs that depends on an analog input. Trimmer Potentiometer and Analog joystick used to test the code.

 

  • 10 3MM LEDs
  • 470 E Series Resistor to limit the current to LED
  • 5K Ohms Trimmer Potentiometer/10K Joystick used to test the code

DOWNLOAD SCHEMATIC

Video Available Here

 

 

 

 

 

 

Arduino Code 10 LED Bar-Graph Display / Bar-Graph 5 Voltmeter 


/*
LED bar graph

Turns on a series of LEDs based on the value of an analog sensor.
This is a simple way to make a bar graph display. Though this graph uses 10
LEDs, you can use any number by changing the LED count and the pins in the
array.

This method can be used to control any series of digital outputs that depends
on an analog input.

The circuit:
– LEDs from pins D2 through D11 to ground
-Trimmer Potentiometer 5K on A0

*/

// these constants won’t change:
const int analogPin = A0; // the pin that the potentiometer is attached to
const int ledCount = 10; // the number of LEDs in the bar graph

int ledPins[] = {
2, 3, 4, 5, 6, 7, 8, 9, 10, 11
}; // an array of pin numbers to which LEDs are attached

void setup() {
// loop over the pin array and set them all to output:
for (int thisLed = 0; thisLed < ledCount; thisLed++) {
pinMode(ledPins[thisLed], OUTPUT);
}
}

void loop() {
// read the potentiometer:
int sensorReading = analogRead(analogPin);
// map the result to a range from 0 to the number of LEDs:
int ledLevel = map(sensorReading, 0, 1023, 0, ledCount);

// loop over the LED array:
for (int thisLed = 0; thisLed < ledCount; thisLed++) {
// if the array element’s index is less than ledLevel,
// turn the pin for this element on:
if (thisLed < ledLevel) {
digitalWrite(ledPins[thisLed], HIGH);
}
// turn off all pins higher than the ledLevel:
else {
digitalWrite(ledPins[thisLed], LOW);
}
}
}


 

 

4 Channels Optically Isolated I/O Board Using 6N137 Optocoupler

4 Channel Opto isolated board has been designed around 6N137 Opto-coupler, the 6N137 optocoupler is designed for use in high-speed digital interfacing applications that require high-voltage isolation between the input and output. Applications include line receivers, microprocessors or computer interface, digital programming of floating power supplies, motors, and other control systems.

The 6N137 high-speed optocoupler consists of a GaAsP light-emitting diode and an integrated light detector composed of a photodiode, a high-gain amplifier, and a Schottky-clamped open-collector output transistor. An input diode forward current of 5 milliamperes will switch the output transistor low, providing an on-state drive current of 13 milliamperes (eight 1.6-milliampere TTL loads).

Note : For 3.3 Input Signal R1, R4, R7, R10 = 220E

Features

  • Supply 5V DC
  • Input Signal : 5V DC TTL
  • Header Connectors for Inputs & Outputs
  • D1 Power LED

 

 

 

 

40Pin/28Pin dS PIC Development/Evaluation Board

The ds PIC Development Board is a development and evaluation tool that helps create embedded applications using dsPIC30F Digital Signal Controllers for motor control family. Sockets are provided for 28 and 40-pin devices in the motor control family.

The dsPIC Development has been designed mainly for Motor dsPIC30F4011 Digital Signal Controller in the 40-pin motor control socket and dsPIC30F4012 28 Pin digital signal controller, the board can also be used with other ds PIC ICs. Board provided with 3.3V and 5V regulator, crystal oscillators, a programming   connector. In addition, the board is populated with dual header connector for all I/O ,reverse supply protection diode, onboard 3.3V & 5V LED , Screw terminal for supply input, push button switch for reset, 6 pin header connector for programming, serial communication  header connector, jumpers for multi serial communication option , electrolytic capacitor for filters. Optional provision for LM317T  TO220 Regulator for 3.3V and 5V and Jumper for 3.3V or 5V power supply selection to power up the dsPIC.

  • Dual sockets for  28 and 40-pin PDIP  devices
  • On Board Reverse Supply Input Socket
  • Supply Input 7V to 15V ( LM7805 & LM1117-3.3V) Regulators
  • Optional Supply Input 7V to 36V DC If Populate LM317T TO220 IC
  • Sample application programs and project files available from microchip
  • website  for supported dsPIC30F devices
  • dsPIC30F4011 40-pin PDIP and dsPIC30F4012 28-pin PDIP
  • On Board Dual 5V & 3.3V regulator provided to full fill low and
  • TTL supply requirement.
  • On Board programming Header Connector
  • On Board 3.3V & 5V Power LED
  • Jumper to select 3.3V or 5V going to dsPIC
  • Jumper for 2 UART Port or CAN selection
  • Controller Area Network (CAN) interface
  • 1 push button for Reset
  • Access to all pins on the dsPIC30F device sockets via Dual  headers

 

 

 

 

 

 

 

 

 

2 Channel Relay Shield for Arduino UNO Circuit and PCB layout

2 Channel Relay Shield for Arduino UNO Circuit and PCB layout

2 Channel Relay shield for Arduino UNO can be used in several applications like remote control, on/off AC or Dc load and any circuits which required isolated high current and high voltage. Relay 1 connected to Digital pin D2 and Relay 2 can be controlled through D12 of Arduino PIN. Both relay has optocoupler in input for isolation which protect Arduino from any EMI noise and complete isolation between high volt/current at relay outputs.  Relay shield required separate 12V DC. Two LED indicate the Relay operations. J1,J2 provided In case single supply for relay and Arduino required.

  • Input: 12 VDC @ 84 mA
  • D2 and D12 Arduino connected to Relay inputs
  • Solder PCB Jumper J1 and J2 if Shield and Arduino need common supply
  • High TTL Signal Required to Trigger the Relay
  • Output: Two SPDT relay
  • Relay specification: 5 A @ 230 VAC
  • Trigger level : 2 to 12 VDC
  • Header connector for connecting power and trigger voltage
  • LED on each channel indicates relay status
  • Power Battery Terminal (PBT) for easy relay output connection

 

 

 

 

 

17 Channel Optically Isolated I/O Shield for Arduino Uno Using LOC111, PC817,6N137 Opto-couplers

17 Channel Optically Isolated I/O Shield for Arduino Uno

The shield enables you to  interface many things to Arduino Uno , all I/O are optically isolated, The shield consist  8 Channel low speed outputs which can be used for on/off applications. 3 Channel high speed outputs frequency up to 10 MHz using 6N137. 4 Channel slow inputs using PC817 opto-coupler. One high speed input frequency up to 10 MHz using 6N137, and one analog voltage input using LOC111 IC. Board provided with multi option isolated i/o line to integrate multiple sensors and other things.

Features

  • Supply 5V DC
  • 8 Low Speed Outputs for On/Off Slow Operations Using PC817
  • Slow Outputs Connected to Digital Pins D2,D3,D4,D5,D6,D7,D12,D13
  • 3 Channel High Speed Outputs Frequency Upto 10Mhz Using 6N137 Optocoupler
  • 3 High Speed Outputs Connected to PWM Pins D9,D10,D11
  • 4 Channel Low Speed Inputs Connected to Analog Pins A1,A2,A3,A4 (PC817)
  • 1 Channel High Speed Input Connected to Digital Pin D8 Frequency Up to 10Mhz
  • 1 Channel Analog Voltage Input 0 To 5V 

 

PDF Schematic

 

 

 

 

 

2.3 Inch Large Size 3 Digit 7 Segment SPI Display Schematic and PCB using 74HC595 and ULN2803

3 Digit 2.3 inch 7 segments SPI protocol Display module using 74HC595 project will display large size 7 segment 3 digit numbers. 2.3 Inch height, which can be visible over large distance.  More digit can be connected serially to each other easily trough connector.

This circuit is a 3 digit seven segment big display using 74HC595 shift register for easy control by micro-controller. useful circuit to make Timer, stop watch, Score Board, Token No, Vehicle counter at parking and many other applications.

Features

  • Supply 12V DC For Display
  • Supply 5V For logic 75HC595
  • Inputs data TTL signals

 

 

 

DOWNLOAD PDF PCB LAYOUT

DOWNLOAD PDF SCHEMATIC

 

 

 

 

 

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