Using transistor as relay?

-

is possible use transistor (or several transistors) switch no common ground rest of circuit?  relay breaks connection wire doesn't touch rest of circuit...  think optocoupler can that, don't have on hand, have several npn , pnp , darlington transistors.  voltage of external circuit around 15v.

quote
with no common ground rest of circuit?
no.


Arduino Forum > Using Arduino > General Electronics > Using transistor as relay?


arduino

Comments

Post a Comment

Popular posts from this blog

invalid use of void expresion in FlexiTimer2 library

-
Image
hello, first post asking in forum patient if dont correctly   well, im trying make robot evades obstacles , uses interrupts in order distances. ive used flexitimer2 run void function each 5ms, problem whe try verify program says me there error in use of flexitimer.    code: [select] flexitimer2::set(1, 1.0/1000, rastreodistanciamin()); i copy code below, please can tell error , how solve it, ive been loking dont know do. thank you code: [select] #include <flexitimer2.h> #include <servo.h> //motor a int ena = 7; int in1=6; int in2 = 5; //motor b int in3=11; int in4=10; int enb=9; servo cabeza; //hc-sr04 device int echo = 13; int triger = 12; //it use hc-sr04 determine , return distance in front of him int calculodistancia(){   volatile int tiempo;   volatile int distancia;   digitalwrite(triger,low); /* por cuestión de estabilización del sensor*/   delaymicroseconds(5);   digitalwrite(triger, high); /* envío del pulso ultrasónico*/   delaymicroseconds(10);   tiem
Read more

error: a function-definition is not allowed here before '{' token

-
i'm new member. me pls code: [select] void manhinh1(){                              tempc = analogread(adc);   tempc = tempc * 0.48828125;                                          lcd.setcursor(0, 0); lcd.print("nhiet: ");                                      lcd.setcursor(7, 0); lcd.print(tempc);   lcd.setcursor(13,0); lcd.print((char)223);    lcd.setcursor(14,0); lcd.print("c");   if(max > min){     if (tempc > max)            {digitalwrite(fan, low);           lcd.setcursor(2, 1); lcd.print("lam mat.....");}     else if (tempc < min)           {digitalwrite(hot, low);           lcd.setcursor(2, 1); lcd.print("dang suoi...");           delay(10000); }     else if (tempc > min && tempc < max)           {digitalwrite(fan, high);            digitalwrite(hot, high);            lcd.setcursor(2, 1); lcd.print("on dinh!!");}              }    else if (max < min){    lcd.setcursor(0, 1);               
Read more

LED Strip Code

-
i downloaded code. here have several single leds flashing music microphone. in project, instead of single rgb leds, have 5 rgb led strips. need change in code? led strip 10m supernight rgb strip cut 5 equal strips. // arduino pin numbers const int do_pin = 2; const int ao_pin = 0; int sound; int led1 = 8; int led2 = 9; int led3 = 10; int led4 = 11; int led5 = 12;   void setup() {   pinmode(do_pin, input);   pinmode(led1, output);   pinmode(led2, output);   pinmode(led3, output);   pinmode(led4, output);   pinmode(led5, output);   serial.begin(9600); }   void loop() {     if (sound > 31) {     digitalwrite(led1, high);   }     if (sound < 31) {     digitalwrite(led1, low);   }     if (sound > 35) {     digitalwrite(led2, high);   }     if (sound < 35) {     digitalwrite(led2, low);   }     if (sound > 40) {     digitalwrite(led3, high);   }     if (sound < 40) {     digitalwrite(led3, low);   }     if (sound > 45) {     digitalwrite(led4, high);   }     if
Read more