TMP 36 Rpi MCP 3002 TMP = Blazing hot to touch

General project help for Adafruit customers

Moderators: adafruit_support_bill, adafruit

Please be positive and constructive with your questions and comments.
Locked
User avatar
loonhaunt
 
Posts: 81
Joined: Sat Nov 16, 2013 1:40 am

TMP 36 Rpi MCP 3002 TMP = Blazing hot to touch

Post by loonhaunt »

Just a quick question regarding a TMP 36. Do they normally get super hot to the touch. I have one wired to a MCP 3002 by way of a tutorial , connected to 3.3v on a raspberry pi. It is a non-Adafruit tutorial. I really only need to know how hot they should be to touch, I have used the before and don't remember this phenomena?

Thanks

Loon

User avatar
Franklin97355
 
Posts: 23910
Joined: Mon Apr 21, 2008 2:33 pm

Re: TMP 36 Rpi MCP 3002 TMP = Blazing hot to touch

Post by Franklin97355 »

I wouldn't think a "Temperature" sensor should get internally hot but it sounds like a miswiring. Can you post a circuit diagram of your connection or, better yet, a photo?

User avatar
loonhaunt
 
Posts: 81
Joined: Sat Nov 16, 2013 1:40 am

Re: TMP 36 Rpi MCP 3002 TMP = Blazing hot to touch

Post by loonhaunt »

PXL_20211130_121841859_2.jpg
PXL_20211130_121841859_2.jpg (499.13 KiB) Viewed 162 times
I followed this schematic exactly. (Minus the LCD) I thought that the MCP3002 could be sucking more current through the TMP36 GZ, so I then wired up the TMP36GZ with it's own power and ground 3.3v and still got so hot I had to use a plier to pull it off the breadboard. I have used these sensors in lot's of other applications and never had this issue. I am not what the GZ extension means after the TMP36? I bought a batch of ten of these off Amazon, I have tested three of them and they have all overheated. I would send a picture of my breadboard but it is pretty hard to follow as the jumpers I used are quite long.

Thanks for your attention

Dave

User avatar
adafruit_support_bill
 
Posts: 88088
Joined: Sat Feb 07, 2009 10:11 am

Re: TMP 36 Rpi MCP 3002 TMP = Blazing hot to touch

Post by adafruit_support_bill »

A TMP36 normally consumes about 50uA. Any self heating should be less than less than 0.1°C. Not sure what the 'GZ' in the part name is for. It is possible that the devices you purchased on Amazon have a different pinout.

User avatar
loonhaunt
 
Posts: 81
Joined: Sat Nov 16, 2013 1:40 am

Re: TMP 36 Rpi MCP 3002 TMP = Blazing hot to touch

Post by loonhaunt »

I am not sure about the GZ either. I tried them by flip flopping the power and ground while measuring the voltage. I had the pin outs correct I am going to look up the part number when I have time. In the meantime I am going to order some TMP 36's from Adafruit. Found specs for the GZ's online they look the same as what I have been using previously??

Thanks.

Dave

User avatar
loonhaunt
 
Posts: 81
Joined: Sat Nov 16, 2013 1:40 am

Re: TMP 36 Rpi MCP 3002 TMP = Blazing hot to touch

Post by loonhaunt »

Just looked at the image of Adafruit listed TMP36,,,it also had the GZ extension at the end. Maybe I got a bad batch??

User avatar
adafruit_support_bill
 
Posts: 88088
Joined: Sat Feb 07, 2009 10:11 am

Re: TMP 36 Rpi MCP 3002 TMP = Blazing hot to touch

Post by adafruit_support_bill »

Could be a bad batch or maybe some mismarked clones.

Locked
Please be positive and constructive with your questions and comments.

Return to “General Project help”