Can Ultrasonic SR-04 sensor to blow up from 8.4v voltage powered on board?

Hi.
I used for power my robot 2 cells Li-Po 3.8v in serial. And it power as motors, as controller, as sensors.
As in the set was not any power regulators, i supposed, that I can use this power supply as is and fit it into special round socket on Arduino PCB in spite of arduino declared powered is 5.5 v.
So, I supposed, that Arduino on board can to create 5.5 V from 8.4-7.6-6.0 v (i mean, when cells are to be weak)
It all works many times, but yesterday I run the test (in attach), (it’s for measure distance and blinking faster, if object nearer).
So, i start to move object, and it start blinking faster at 30 cm, and move it nearer it start more faster after 20 cm to sensor. Than I just increased distance, but LED not star blinking slowly!

When i attach serial monitor, I saw, that it measure always 0 cm, so it properly show distance less than 20 cm.

1.As i make this operation many times before, and all was ok, can it be just blown up the sensor?

2 .Can I use 7.6 v or 8.4 for power ALL robot circuits (if in this set not have alternative power sources) or may be expirienced users divide it ? (but i read of coarse, that arduino can be powered by more, than 5 v)

3.Does somebody used the cells set, included in robot set as is or need to decrease it’s voltage some way (by step down regulator or use only one cell and use step up or something else?)

4.what is happen, when I power off my robot and start programming by USB - will USB port in my tablet MS SURFACE PRO blow up, because powered robot with motors?

  1. what happen if I make testing program and attach serial monitor, while robot powered up with it’s 7,6-8.4 volts - can it damage USB in MS SUrface? (because uSB voltage is 5 v and here is more, than 50% higher?)

  2. Can it was because just ECHO sensor was blown if to decrease distance to obstacle to 0 can be to much noice level?

7.Does somebody tried to repair it?

Thanks

ultrasonic.ino (2.85 KB)

anton1o:
Hi.
I used for power my robot 2 cells Li-Po 3.8v in serial.

I'm guessing you meant "in series"?

Based on the information in the other thread, I think you're using two Li-Ion cells in series. Li-Ion and LiPo cells can have voltages over 4.2V when freshly charged so you battery pack likely have a voltage of about 8.4V when freshly charged.

anton1o:
. . . As in the set was not any power regulators, i supposed, that I can use this power supply as is and fit it into special round socket on Arduino PCB in spite of arduino declared powered is 5.5 v.
So, I supposed, that Arduino on board can to create 5.5 V from 8.4-7.6-6.0 v

Yes, the Arduino likely has a voltage regulator to reduce the 8.4V to 5.0V.

anton1o:
. . .

4.what is happen, when I power off my robot and start programming by USB - will USB port in my tablet MS SURFACE PRO blow up, because powered robot with motors?

I don't know the answer. I think it's usually okay to use external power while an Arduino is connected to a computer with a USB cable but I've owned a few boards which state external power should be used while the board is connected via USB.

I think it's probably okay to use the USB and external power but if you provide a link to the board you're using, we can double check.

You want to make sure the motors aren't being powered from the USB.

I noticed from your other thread, you think the ultrasound sensor is broken.

Have you tested the sensor with simple code?

Try this program.

#define TRIGGER_PIN 13
#define ECHO_PIN 11
//const long DOUBLE_SPEED_OF_SOUND = 34 * 2; // 340.29 m/s or micrometers/microseconds
const int IMPERICAL_CONVERSION = 56;
const int BETWEEN_PULSE_DELAY = 100;
const int PULSE_DELAY = 10;

void setup() 
{
  Serial.begin(9600);
  pinMode(TRIGGER_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  Serial.println("Ultrasound Simple Test");
  
}
void loop()
{
  digitalWrite(TRIGGER_PIN, HIGH);
  delayMicroseconds(PULSE_DELAY);
  digitalWrite(TRIGGER_PIN, LOW);

  int distance = pulseIn(ECHO_PIN, HIGH) / IMPERICAL_CONVERSION; // in centimeters
 
  Serial.print("distance = ");
  Serial.print(distance);
  Serial.println(" cm");
 
  delay(BETWEEN_PULSE_DELAY);
  
}

Make sure you change the values of "TRIGGER_PIN" and "ECHO_PIN" to match the pins you're using.

The ultrasound should be powered with 5V.

Do you have a multimeter? It might be a good idea to measure the voltage of your battery pack and it would also be good to measure the voltage of the 5V line on your board to make sure the regulator is working correctly.