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MCP23017 chip becomes very hot, used with a raspberry pi
Moderators: adafruit_support_bill, adafruit

MCP23017 chip becomes very hot, used with a raspberry pi

by sky99 on Sun Jan 20, 2013 12:51 am

Hello!
I got a MCP23017 chip to work with one of my raspberries. I can blink a LED and control it.
However, i am a little concerned by the temperature of the chip, it is burning hot, and i measured
at least 75°C with a TMP36 and a MCP3008 DAC on the same raspberry pi.
Is it normal? the chip has been running at this high temperature for at least 10 hours.

What do you think?

sky99
 
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Joined: Sat Nov 24, 2012 10:00 am

Re: MCP23017 chip becomes very hot, used with a raspberry pi

by adafruit_support_bill on Sun Jan 20, 2013 7:59 am

That does sound warmer than normal. Are you using a current limiting resistor on your LED?

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Re: MCP23017 chip becomes very hot, used with a raspberry pi

by sky99 on Sun Jan 20, 2013 9:15 am

Hi,
I have a resistor, and i also removed the LED (so the circuit for the LED is opened, and nothing is plugged in),
but the chip is still very hot.

sky99
 
Posts: 11
Joined: Sat Nov 24, 2012 10:00 am

Re: MCP23017 chip becomes very hot, used with a raspberry pi

by adafruit_support_bill on Sun Jan 20, 2013 9:28 am

It should not be hot at all with no load. What do you have connected besides VDD & VSS?

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Re: MCP23017 chip becomes very hot, used with a raspberry pi

by sky99 on Sun Jan 20, 2013 11:56 am

My wiring is :

  • VDD to +3.3v
  • VSS to ground
  • SCL to pi cobler SCL
  • SDA to pi cobler SDA
  • A0 to ground
  • A1 to ground
  • A2 to ground
  • RESET to +3.3v

Right now, i have a LCD connected, but i did try with nothing connected beside the pins in the list (no load), and the chip temperature did not get any lower.

sky99
 
Posts: 11
Joined: Sat Nov 24, 2012 10:00 am

Re: MCP23017 chip becomes very hot, used with a raspberry pi

by adafruit_support_rick on Sun Jan 20, 2013 5:48 pm

Can you post a picture of your wiring and assembly?

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