short circuited 5V to ground

[ferdywallinx]

I am working with the TSL-235R and I get some readings from it and then it stops. When I tried to see if there was a current problem I connected a multimeter in between the 5V (physical pin 2 or 4) and GROUND. For a few seconds this showed 5V and then dropped to 0.15V. The same result happened with both pins. When I reboot and keep unplugged for a few minutes it works again so I reckon it has something to do with a capacitator?

Sorry if this is a really dumb question but I cannot figure it out.

[BMS Doug]

I am working with the TSL-235R and I get some readings from it and then it stops. When I tried to see if there was a current problem I connected a multimeter in between the 5V (physical pin 2 or 4) and GROUND. For a few seconds this showed 5V and then dropped to 0.15V. The same result happened with both pins. When I reboot and keep unplugged for a few minutes it works again so I reckon it has something to do with a capacitator?

Sorry if this is a really dumb question but I cannot figure it out.

The thermal fuse tripped out, when allowed to cool it reset.

[ferdywallinx]

Could this be the same cause why my TSL-235R (http://www.ams.com/eng/content/download ... 925/142301) is not working? It is a chip that is connected to 5V or 3.3V and to ground, with a third pin going to GPIO 18 PWM and puts out a signal between 100-500.000 Hz. When the light intensity is normal indoors it works but if I increase the light temporarily it stops working and does not continue for a while even after I removed the extra lightsource. If so, how can I solve this?

[BMS Doug]

Could this be the same cause why my TSL-235R (http://www.ams.com/eng/content/download ... 925/142301) is not working? It is a chip that is connected to 5V or 3.3V and to ground, with a third pin going to GPIO 18 PWM and puts out a signal between 100-500.000 Hz. When the light intensity is normal indoors it works but if I increase the light temporarily it stops working and does not continue for a while even after I removed the extra lightsource. If so, how can I solve this?

so you have a photodiode with built in frequency converter giving you a frequency output of up to 500 kHz.
you have connected the Vdd of the frequency converter to 5V and the output to pin 18 (which you have setup as an input).

As a result you are putting 5V onto your GPIO input which is only 3v3 tolerant and damaging the Pi. The chances are that the Pi is already irreversibly damaged and will eventually stop working entirely (as the damage slowly spreads).

what you could have done is connect the TSL-235R to the 3v3 rail instead of the 5v rail (the datasheet says that this chip will work with a Vdd as low as 2v7) then the output would have been safe for the Pi's GPIO inputs.

[ferdywallinx]

Well that is quite a bummer. I'm trying to test now whether I really destroyed my Pi but it does not seem good. Though the GPIO-test of WiringPi shows no damaged pins.

However, I did have the same issues with the 3V3 pin for the sensor. So Vdd to 3v3, GND to GND and PWM output to GPIO 18. And basically the same thing happened: I sometimes get a value and then when I increase the intensity, thus the frequency to GPIO 18, it stops measuring and I have to wait for a long time before it works again.