I have connected on a pic 16f18346 a sensor BH1750 and trying to control it with a 2n2222 transistor but i fail. I get calculations from some tutorials but i am not sure where i am wrong. The output from the IO pin is measured 4.97vdc. The BH1750 Operating current: 120uA (typ) 190uA (max). Is possible someone to help here with the calculations of the resistors as swon on the schematic please.

 

Are you sure the pin numbers are correct for the BH1750?
Post a link or model # of the sensor please.

 

Can't help without knowing the CON7 pinout going the the BH1750.
What are pins 1, 2, and 5 connected to?

 

It also appears the TS is trying to control the sensor by switching a ground to the module which I wouldn't recommend as it has SD and SCL lines.

 

Confirm the pinout of 2N2222. There are different versions.

 

Even if that's not the case and the module has a ground elsewhere, the TS needs to be sure that the module behaves properly when whatever input that is is left floating.

It would also be nice to know what "trying to control it" means, and what "failing" means.

Providing a link to the parts being discussed, such as this BH1750, would be a bonus, instead of expecting people being asked for free help to go searching out what our best guess is that they mean.

If it's the BH1750 that I tracked down, this it's far from unclear what two pins are that he is pulling down with that transistor. About the only possibility, though, is that he is hard shorting the module's 3.3 V output to the module's ground, and then either pulling them both down to the microcontroller's ground or letting them float. Of course, doing either of those makes zero sense, but that's the best guess I can make since my mind-reading skills aren't up to what the TS is expecting.

 

Can't help without knowing the CON7 pinout going the the BH1750.
What are pins 1, 2, and 5 connected to?

PIN 4 is th ADDR
PIN 5 is the GROUND

 

Confirm the pinout of 2N2222. There are different versions.

View attachment 353149

confirm left type 2n2222 A331 TO-92 (image)

 

PIN 4 is th ADDR
PIN 5 is the GROUND

On your drawing pins 4 and 5 are something else.

 

This is a an image of one such module with a pin out the same as others. I’d be surprised if they vary between suppliers

 

A datasheet: https://www.mouser.com/datasheet/2/348/bh1750fvi-e-186247.pdf

Which has the maximum voltage as 4.5 V so the 5V is out of range. Perhaps this isn't the
correct part (multiple sources?) and his has a higher voltage limit?

 

It depends on the PCB circuit details.
The BH1750 chip requires 3 VDC to operate.
The Adafruit BH1750 Ambient Light Sensor has on-board voltage regulator that will accept 3-5 VDC input.

 

PIN 4 is th ADDR
PIN 5 is the GROUND

Yet your first post shows Pin 4 connected to SCL1 and Pin 5 connected to +5 V

 

This is a an image of one such module with a pin out the same as others. I’d be surprised if they vary between suppliers View attachment 353171

I'd be more surprised if they didn't, unless there is some standardization, at least defacto, for this module, which I'm not seeing any indication of:

 

I have connected on a pic 16f18346 a sensor BH1750 and trying to control it with a 2n2222 transistor but i fail. I get calculations from some tutorials but i am not sure where i am wrong. The output from the IO pin is measured 4.97vdc. The BH1750 Operating current: 120uA (typ) 190uA (max). Is possible someone to help here with the calculations of the resistors as swon on the schematic please.

View attachment 353147

Lower R7 to increase the bias current.

 

Lower R7 to increase the bias current.

Hi all. Thanks for the inputs. Unfortunately all was a mistake by me. The R7 by some kind of mistake in all circuits was 100k. I messed the bags when i stored them. So now everything works. The puspose of all this was to save a bit battery and then i found that the senso's by themselves have eco modes or they shut down. So i left the approach with the transistor switch and i coded with the eco modes.
Thank you for your inputs and the time you spend, sorry because was a faulty alarm.