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Tb6612fng current lost?


#1

So Im making a project where I transform this RC toy car into a Bluetooth controlled car using arduino Unfortunately I threw it’s previous board so I have to use tb6612fng. I follow some tutorial on how to make this and somehow manage to make it work but problem it cant move or it has no torque to do so it rotates well with no load when I lift my car but cant move if it’s on flat surface. I just hear some hi pitch sound and sometimes even with no load still wont turn unless I help it a little.
so my motor is a 130 DC motor geard idk what ratio but ti should work since it’s like this since it was a working toy.
I power it with first a 9V box type battery then tried a powerbank 5V 2A both didn’t seems to work, couldn’t check the current since my VOM already has a blown fuse from idiotically trying to measure the current. voltage is fine tho 9V or 5V if powerbank.
so do I need a better Power supply or Is my tb6612fng broken? btw in my code the pwm is at 250 since writing HIGH don’t seems to work.
I didn’t want to control the speed first since I’m still learning how to even make this work.
and btw don’t know if I get this right but the resistance at the output of one of the motor seems pretty high that my VOM can’t measure, I tired to calculate the current with the V=IR formula


Tb6612fng blew up, is there a way to save it or just trash it?
#2

Hello.

It is possible that neither of your supplies could provide enough power for your motors. Generally 9V batteries are a pretty bad at sourcing current and not recommended for powering motors and your 130 size motors could draw a lot of current. One way to test if your supply is adequate would be to directly connect it to your motors and run them under load. If that works, you could then focus on integrating your motor driver. If you encounter problems after that, you might try following the General Troubleshooting Advice section on our general support page.

By the way, that is not our TB6612FNG carrier so we can only provide general advice. If after looking into your system some more you determine that you need to troubleshoot your driver, I recommend contacting the manufacturer.

-Tony


#3

I tired it running directly at my 9V and it seems to be accelerating a little bit definitely better than on the driver and its even better if I directly attached it to my power bank which provide 1-2A even with full load. one thing I noticed is that when I tried to accelerate it with no load (on the driver) it seems to start off slow then after few sec it starts speeding up, I didn’t put any codes that delay the power or anything, in my code its always at full power.
so my driver is probably my fault right? I may have damaged it during soldering or the manufacturer send me a defective one


#4

or could my code b shorting it?

#define m11 11    // rear motor
#define m12 10
#define m21 8    // front motor
#define m22 9
#define STBY 7
#define PF 6 
#define PR 5

char str[2],i;

void forward()
{
   digitalWrite(STBY, HIGH);
   digitalWrite(PR, 250);
   digitalWrite(PF, 250);
   digitalWrite(m11, LOW);
   digitalWrite(m12, HIGH);
   digitalWrite(m21, LOW);
   digitalWrite(m22, LOW);
}

void backward()
{
   digitalWrite(STBY, HIGH);
   digitalWrite(PR, 250);
   digitalWrite(PF, 250);
   digitalWrite(m11, HIGH);
   digitalWrite(m12, LOW);
   digitalWrite(m21, LOW);
   digitalWrite(m22, LOW); 
}

void left()
{
   digitalWrite(STBY, HIGH);
   digitalWrite(PR, 250);
   digitalWrite(PF, 250);
   digitalWrite(m11, LOW);
   digitalWrite(m12, LOW);
   delay(100);
   digitalWrite(m21, LOW);
   digitalWrite(m22, HIGH);
}

void right()
{
   digitalWrite(STBY, HIGH);
   digitalWrite(PR, 250);
   digitalWrite(PF, 250);
   digitalWrite(m11, LOW);
   digitalWrite(m12, LOW);
   delay(100);
   digitalWrite(m21, HIGH);
   digitalWrite(m22, LOW);
}

void Stop()
{
   digitalWrite(STBY, HIGH);
   digitalWrite(PR, 250);
   digitalWrite(PF, 250);
   digitalWrite(m11, LOW);
   digitalWrite(m12, LOW);
   digitalWrite(m21, LOW);
   digitalWrite(m22, LOW);
}

void setup() 
{
  Serial.begin(9600);
  pinMode(m11, OUTPUT);
  pinMode(m12, OUTPUT);
  pinMode(m21, OUTPUT);
  pinMode(m22, OUTPUT);
}

void loop() 
{
  while(Serial.available())
  {
    char ch=Serial.read();
    str[i++]=ch;

    if( Serial.available()){
      
    }

    
    if(str[i-1]=='1')
    {
     Serial.println("Forward");
     forward();
     i=0;
    }

    else if(str[i-1]=='2')
    {
     Serial.println("Left");
     right();
     i=0;
    }

    else if(str[i-1]=='3')
    {
      Serial.println("Right");
      left();
      i=0;
    }
    
    else if(str[i-1]=='4')
    {
      Serial.println("Backward");
      backward();
      i=0;
    }

    else if(str[i-1]=='5')
    {
      Serial.println("Stop");
      Stop();
      i=0;
    }
    delay(100);
  }
}

#5

It seems possible that both your supply and your driver could be underpowered, since you are noticing this acceleration behavior from both the supply alone and the driver.

-Tony


#6

Hi thanks, I tired changing my power supply to much better one, although it’s still not as good as when I just directly attached the battery to the motor its now at a way more better power, but now I have a problem where my tb6612fng goes into Thermal Shutdown, and my dc motor going quite hot for a long time, I use a 11.7V 1.3Ah battery form a drill, I now able to prevent the thermal shutdown by reducing the pwm signal to around 150, and about the motor maybe it’s because the voltage is too high for it my motor is just a normal 130 dc motor which I think is rated at 3-v, so where should I put the voltage regulator? before the tb66 at the output of tb66? can I just use a voltage divider to reduce the voltage? thank you so much


#7

as the title say is there a way to save this thing and even if I did will it still be as safe?
I see a burnt something if I replace this will it be fine? I accidentally reversed the power and ground in the vm pin, my Arduino is still connected to it but for now(haven’t test it) my Arduino seems fine. but I wanna know if I can still save this and would much rather avoid ordering another one since 1 the cost of this is worth 4-5 meals, 2 ordering it takes 1 week at best.
IMG_20190109_173119


#8

I merged your posts together since you are asking about the same board. Unfortunately, if it looks burnt it is best not to use it.

-Tony


#9

yeah had to borrow one form my friend, Im only maintaining 150pwm strength as it’s the one way I know so it won’t thermal shutdown