Mirko Pavleski
NORTH MACEDONIA • + Follow
Components
|
|
ARDUINO_NANO |
x 1 | |
|
|
I2C 16x2 Arduino LCD Display Module |
x 1 | |
|
|
button |
x 4 | |
|
|
resistors |
x 6 | |
|
|
capacitor 470µF |
x 1 |
Tools, APP Software Used etc.
|
arduino IDEArduino
|
|
|
Soldering Iron Kit |
Description
How to make Arduino LED Tester + Resistor Calculator
Light Emitting Diode as an electronic component are very often used in electronic devices. There are many different types with specific characteristics such as forward voltage and maximum current. Most often it is necessary to connect them to a higher voltage where it is necessary to connect a series resistor with a certain value.
The device described in this video is a useful tool for testing, and determining characteristics of LEDs, as well as a calculator for calculating the series resistor depending on the connected voltage.
The idea for this project was taken from Dave Cook's model, processed with an Arduino from Jaycar Electronics, and I made some changes to the code where uses an I2C LCD display, and dedicated buttons to control the device, instead of an LCD keypad shield.
The device is very simple to build, and consists of several components:
- Arduino Nano microlontroller
- 16x2 LCD Display with I2C communication protocol
- 7 Resistors
- capacitor
- and four Buttons
If you want to make a PCB for this project, or for any other electronic project, PCBway is a great choice for you. PCBway is one of the most experienced PCB manufacturing company in China in field of PCB prototype and fabrication. They provide completed PCB assembly service with worldwide free shipping , and ISO9001 quality control system. Also, on their site there is an online gerber viewer where you can upload your gerber and drill files to render your board.
And now let's see how the tester works in real conditions. When turning on the display appear previously defined values for the current and voltage to which the LED would be connected, namely a current of 10mA and a voltage of 14V. With no LED attached, it will not show a resistor value, and current value blinking.
The upper buttons can be used to set the current that will flow through the LED in the range from 1 to 20mA. These are values that in most cases cannot cause damage to the LED. The lower buttons set the value of the voltage to which the diode would be connected through a series resistor in the real circuit. This voltage can be set from 1 to 99 V, and the display then shows the required resistor value depending on the selected voltage and current. Also on the lower right part of the display appears the code of that resistor under which we can buy it in Jaycar Electronic shop. If the resistor would dissipate more than half a watt, a P flashes on the top line to let you know you might need to choose a more powerful resistor. If by mistake we connect the diode with reverse polarity, the diode remains functional, it just won't light up.
And finally a short conclusion. The device presented in this project is very simple to build, but it is a really useful instrument in the laboratory, especially due to the fact that many different types of LEDs are used nowadays. The device is embedded in a suitable box made of PVC material and lined with self-adhesive colored wallpaper
Code
code
C/C++
/* Arduino LED Tester DPIN--39R--+--10R---TESTLED---GND | | | 470u ATOP ABOT | GND Measures LED characteristics by charging up the cap to deliver target current and find forward voltage From target current, we can calculate R to be used with a design supply voltage and a matching part number. */ //lcd update interval //key check interval //pin for buttons //button constants LiquidCrystal_I2C lcd(0x27,16,2); // set the LCD adress //Globals for display long itest=10; //test current, in mA long vset =14000; //display voltage in mV long vled,vrr,irr,pset; //LED voltage, Resistor voltage, resistor current, display power //resistors in Jaycar 1/2 W range, part nos start at RR0524 for 10R long rvals[]={10,11,12,13,15,16,18,20,22,24,27,30,33,36,39,43,47,51,56,62,68,75,82,91,100,110,120,130,150,160,180,200,220,240,270,300,330,360,390,430,470,510,560,620,680,750,820,910,1000,1100,1200,1300,1500,1600,1800,2000,2200,2400,2700,3000,3300,3600,3900,4300,4700,5100,5600,6200,6800,7500,8200,9100,10000,11000,12000,13000,15000,16000,18000,20000,22000,24000,27000,30000,33000,36000,39000,43000,47000,51000,56000,62000,68000,75000,82000,91000,100000,110000,120000,130000,150000,160000,180000,200000,220000,240000,270000,300000,330000,360000,390000,430000,470000,510000,560000,620000,680000,750000,820000,910000,1000000}; long lastlcd=0; //time of last lcd update long lastkey=0; //time of last key check int lcdflash=0; //lcd flashing phase variable long pdes; long rval; //calculated resistor value for display long rindex; //index of selected resistor in rvals[] int pwmout=0; //pwm output of current driver int rvalid=0; //flag if resistor value is valid //pins for test interface void setup() { Serial.begin(9600); // lcd.begin(16, 2); //lcd lcd.begin(); lcd.clear(); lcd.backlight(); pinMode(DPIN,OUTPUT); //pwm pin } void loop() { long atop,abot,arr; //analog sample values rvalid=0; //set flag to not valid atop=analogoversample(ATOP,OSAMP)/OSAMP; abot=analogoversample(ABOT,OSAMP)/OSAMP; arr=atop-abot; //this is the analog value across the 10R sense resistor if(arr<0){arr=0;} //sanity check vled=abot*5000/1023; //5000mV=1023 => voltage across LED vrr=arr*5000/1023; //voltage across sense resistor irr=vrr/10; //led and resistor current in mA (cos it's a 10R resistor) if(irr<itest){pwmout++;if(pwmout>255){pwmout=255;}} //ramp up current if too low if(irr>itest){pwmout--;if(pwmout<0){pwmout=0;}} //ramp down if too high if(irr>24){pwmout=pwmout-5;if(pwmout<0){pwmout=0;}} //ramp down quick if too too high if(irr>itest*3){pwmout=pwmout-5;if(pwmout<0){pwmout=0;}} //ramp down quick if too too high analogWrite(DPIN,pwmout); //output new PWM rval=(vset-vled)/itest; //mV/mV => ohms resistance of display resistor for(int i=0;i<RCOUNT;i++){ //find next highest E24 value if(rvals[i]>=rval){rindex=i;rval=rvals[rindex];i=RCOUNT+1;rvalid=1;} } if(abs(irr-itest)>(itest/5)+1){rvalid=0;} //has current settled within 20%? if(vled>vset){rvalid=0;} //if vled>vset, no valid resistor exists pset=0; //work out dissipation in ballast resistor if valid) if(rvalid){pset=itest*itest*rval;} //this will be in microwatts (milliamps squared) if(millis()-lastlcd>LCDINT){ //check if display due to be updated lastlcd=millis(); dolcd(); //update display lcdflash=1-lcdflash; //toggle flash variable } if(millis()-lastkey>KEYINT){ //check if keys due to be checked lastkey=millis(); dobuttons(); } delay(1); } //end of loop void dolcd(){ lcd.setCursor(0,0); //first line //milliamps if(lcdflash||rvalid){ //show if correct if on flashing phase if(itest>9){lcd.write(((itest/10)%10)+'0');}else{lcd.write(' ');} //blank tens if zero lcd.write((itest%10)+'0'); } else{ //blank if not lcd.write(' ');lcd.write(' '); } lcd.write('m');lcd.write('A');lcd.write(' '); //VLED lcd.write(((vled/1000)%10)+'0'); lcd.write('.'); lcd.write(((vled/100)%10)+'0'); lcd.write('V');lcd.write(' '); //actual LED current if(irr>9){lcd.write(((irr/10)%10)+'0');}else{lcd.write(' ');} //blank tens if zero lcd.write((irr%10)+'0'); lcd.write('m');lcd.write('A');lcd.write(' '); if((pset>499999)&&(lcdflash)){lcd.write('P');}else{lcd.write(' ');} //flash P if power above 1/2 watt lcd.setCursor(0,1); //second line // if(vset>9999){lcd.write(((vset/10000)%10)+'0');}else{lcd.write(' ');} //tens of vset, blank if zero lcd.write(((vset/1000)%10)+'0'); //units of vset lcd.write('V');lcd.write(' '); if(rvalid){ lcdprintrval(rval); //resistor value (4 characters) lcd.write(' '); lcdprintpartno(rindex); //resistor part no (6 characters) if(pset>499999){lcd.write('!');}else{lcd.write(' ');} //show ! if power above 1/2 watt }else{ lcd.write(' '); lcd.write('-'); lcd.write('-'); lcd.write('-'); lcd.write(' '); lcd.write('-'); lcd.write('-'); lcd.write('-'); lcd.write('-'); lcd.write('-'); lcd.write('-'); lcd.write(' '); } } void lcdprintpartno(int index){ //part number lcd.write('R'); lcd.write('R'); lcd.write('0'); lcd.write((((index+524)/100)%10)+'0'); //part no's start at RR0524 for 10R lcd.write((((index+524)/10)%10)+'0'); lcd.write((((index+524))%10)+'0'); } void lcdprintrval(long rval){ //print a value in 10k0 format, always outputs 4 characters long mult=1; long modval; if(rval>999){mult=1000;} if(rval>999999){mult=1000000;} modval=(10*rval)/mult; //convert to final format, save a decimal place if(modval>999){ //nnnM lcd.write(((modval/1000)%10)+'0'); lcd.write(((modval/100)%10)+'0'); lcd.write(((modval/10)%10)+'0'); lcdprintmult(mult); }else{ if(modval>99){ //nnMn lcd.write(((modval/100)%10)+'0'); lcd.write(((modval/10)%10)+'0'); lcdprintmult(mult); lcd.write(((modval)%10)+'0'); }else{ //_nMn lcd.write(' '); lcd.write(((modval/10)%10)+'0'); lcdprintmult(mult); lcd.write(((modval)%10)+'0'); } } } void lcdprintmult(long mult){ //helper function to print multiplier switch (mult){ case 1: lcd.print('R');break; case 1000: lcd.print('k');break; case 1000000: lcd.print('M');break; default: lcd.print('?');break; } } int read_LCD_buttons(){ int adc_key_in = 0; adc_key_in = analogRead(KEYPIN); // read the value from the sensor delay(5); //switch debounce delay. Increase this delay if incorrect switch selections are returned. int k = (analogRead(KEYPIN) - adc_key_in); //gives the button a slight range to allow for a little contact resistance noise if (5 < abs(k)) return btnNONE; // double checks the keypress. If the two readings are not equal +/-k value after debounce delay, it tries again. // my buttons when read are centered at these valies: 0, 144, 329, 504, 741 // we add approx 50 to those values and check to see if we are close if (adc_key_in > 1000) return btnNONE; // We make this the 1st option for speed reasons since it will be the most likely result if (adc_key_in < 50) return btnRIGHT; if (adc_key_in < 195) return btnUP; if (adc_key_in < 380) return btnDOWN; if (adc_key_in < 555) return btnLEFT; if (adc_key_in < 790) return btnSELECT; return btnNONE; // when all others fail, return this... } void dobuttons(){ //updates variables. debounces by only sampling at intervals int key; key = read_LCD_buttons(); if(key==btnLEFT){itest=itest-1;if(itest<1){itest=1;}} if(key==btnRIGHT){itest=itest+1;if(itest>20){itest=20;}} if(key==btnUP){vset=vset+1000;if(vset>99000){vset=99000;}} if(key==btnDOWN){vset=vset-1000;if(vset<0){vset=0;}} } long analogoversample(int pin,int samples){ //read pin samples times and return sum long n=0; for(int i=0;i<samples;i++){ n=n+analogRead(pin); } return n; }
Schematic and Layout
Schematic
Schematic.jpg
Nov 24,2023
663 views
end-flag
How to make Arduino LED Tester + Resistor Calculator
Useful tool for testing, and determining characteristics of LEDs, as well as a calculator for calculating the series resistor depending on
663
0
0
Published: Nov 24,2023
PCBWay Donate 10% cost To Author
Under the
Attribution-ShareAlike (CC BY-SA)
License.
Raspberry Pi 5 7 Inch Touch Screen IPS 1024x600 HD LCD HDMI-compatible Display for RPI 4B 3B+ OPI 5 AIDA64 PC Secondary Screen（Without Speaker）
BUY NOW
ESP32-S3 4.3inch Capacitive Touch Display Development Board, 800×480, 5-point Touch, 32-bit LX7 Dual-core Processor
BUY NOW
Raspberry Pi 5 7 Inch Touch Screen IPS 1024x600 HD LCD HDMI-compatible Display for RPI 4B 3B+ OPI 5 AIDA64 PC Secondary Screen（Without Speaker）
BUY NOW
- Comments(0)
- Likes(0)
Log in to post comments.
Upload photo
0 / 10000
More by Mirko Pavleski
-
DIY ESP32 Bioresonance Rife Machine with ZAPPER function
Rife machine therapy is an alternative treatment developed by Dr. Royal Raymond Rife in the 1930s. H...
-
Arduino VFO Project with a Large LCD Display
A Variable Frequency Oscillator (VFO) is an electronic oscillator whose output frequency can be adj...
-
Exploring the Tesla Coil Driver Board, Full Review & Test Results
Some time ago I presented you a video in which I analyzed a super cheap Tesla Coil driver that cost...
-
Arduino Eatrthquake alarm and protection system with D7S seismic Sensor
Earthquakes are extremely common events around the world. On average, there are fifty earthquakes a...
-
Review and Comparison of Three Inexpensive Metal Detector Kits
A metal detector is a device used to detect the presence of metal objects in the ground or other ma...
-
How to make simple Arduino RGB Led strip VU Meter
VU meter or volume unit meter is a device intended for visual presentation of the audio signal. It ...
-
Arduino 3D Printed self Balancing Cube
Self-balancing devices are electronic devices that use sensors and motors to keep themselves balanc...
-
OpenWebRX - Simplest Rasprberry Pi + RTLSDR Web SDR Radio
Software-Defined Radio is a radio communication system where components that have traditionally bee...
-
Colorful Arduino Tetris Game - WS2812B LED Matrix Tutorial
Tetris is a puzzle video game created in 1985 by Alexey Pajitnov. Players manipulate falling geomet...
-
Ultra cheap Ultrasonic levitation Device - functionality and testing
Ultrasonic levitation is phenomenon where objects are suspended in mid-air using the power of sound ...
-
DIY -Spirit PI- ESP32 + Smartphone Sensitive Metal Detector
Pulse Induction (PI) metal detector operates on a principle based on sending short pulses of electr...
-
ESP32 Analog style VU meter with GC9A01 Round Dispalys + Peak Meters
A typical VU meter measures audio signals and displays them with a visual indicator. In the classic...
-
Arduino two weel self Balancing Robot
Self Balancing Robot is device that can balance itself from falling to the ground. Its function is ...
-
ELECROW CrowPanel ESP32 4.2” E-paper Wi-Fi Info-Dispaly Project
An e-paper display (also known as an electronic paper display or E Ink display) is a type of screen...
-
ESP32 Fluid simulation on 16x16 Led Matrix
Fluid simulation is a way of replicating the movement and behavior of liquids and gases in differen...
-
Simple GU50 VTTC Tesla Coil with MOT (25+cm Spark)
Vacuum Tube Tesla Coils are a common choice for homebuilders for several practical reasons. At Soli...
-
Hourglass ESP8266 Code
A hourglass, also known as an sand clock, is a device used to measure the passage of time. It consi...
-
Tug of War Arduino Game on WS2812 Led strip
A Tug of War is a classic team-based game where two opposing teams compete to pull a rope in opposi...
-
DIY ESP32 Bioresonance Rife Machine with ZAPPER function
Rife machine therapy is an alternative treatment developed by Dr. Royal Raymond Rife in the 1930s. H...
-
Arduino VFO Project with a Large LCD Display
A Variable Frequency Oscillator (VFO) is an electronic oscillator whose output frequency can be adj...
-
Exploring the Tesla Coil Driver Board, Full Review & Test Results
Some time ago I presented you a video in which I analyzed a super cheap Tesla Coil driver that cost...
-
Arduino Eatrthquake alarm and protection system with D7S seismic Sensor
Earthquakes are extremely common events around the world. On average, there are fifty earthquakes a...
-
Review and Comparison of Three Inexpensive Metal Detector Kits
A metal detector is a device used to detect the presence of metal objects in the ground or other ma...
-
How to make simple Arduino RGB Led strip VU Meter
VU meter or volume unit meter is a device intended for visual presentation of the audio signal. It ...
-
Arduino 3D Printed self Balancing Cube
Self-balancing devices are electronic devices that use sensors and motors to keep themselves balanc...
-
OpenWebRX - Simplest Rasprberry Pi + RTLSDR Web SDR Radio
Software-Defined Radio is a radio communication system where components that have traditionally bee...
-
Colorful Arduino Tetris Game - WS2812B LED Matrix Tutorial
Tetris is a puzzle video game created in 1985 by Alexey Pajitnov. Players manipulate falling geomet...
-
Ultra cheap Ultrasonic levitation Device - functionality and testing
Ultrasonic levitation is phenomenon where objects are suspended in mid-air using the power of sound ...
-
DIY -Spirit PI- ESP32 + Smartphone Sensitive Metal Detector
Pulse Induction (PI) metal detector operates on a principle based on sending short pulses of electr...
-
ESP32 Analog style VU meter with GC9A01 Round Dispalys + Peak Meters
A typical VU meter measures audio signals and displays them with a visual indicator. In the classic...
You may also like
-
Commodore 64 1541-II Floppy Disk Drive C64 Power Supply Unit USB-C 5V 12V DIN connector 5.25
127 1 2 -
Easy to print simple stacking organizer with drawers
75 0 0 -
-
-
Modifying a Hotplate to a Reflow Solder Station
1116 1 6 -
MPL3115A2 Barometric Pressure, Altitude, and Temperature Sensor
628 0 1 -
-
-
V2 Commodore AMIGA USB-C Power Sink Delivery High Efficiency Supply Triple Output 5V ±12V OLED display ATARI compatible shark 100W
1398 4 3
