I am trying to figure out the total Power dissipation is for a 555 IC and a 4017 Johnson Counter.
The 555 is connected in Astable mode and the current is reading 150mA.
My LM7805 is getting very HOT. Too hot to touch. When I measure the 4017 I am showing just from the VSS to common ground around 350mA and at 5V that is 1.7W. This doesn't sound right to me but I am having trouble locating the information in the datasheet that tells me how much current is typically used by that IC.
I am using a resistor on the output clock because without it the lm7805 gets hotter faster.
Attached is a picture of my breadboard.
The LM7805's input is supplied by a 12V 500mA adapter.
The datasheet is found here : http://pdf1.alldatasheet.com/datasheet-pdf/view/17686/PHILIPS/HEF4017BP.html
Can anyone tell me where and or if I am going wrong about this?
The 555 is connected in Astable mode and the current is reading 150mA.
My LM7805 is getting very HOT. Too hot to touch. When I measure the 4017 I am showing just from the VSS to common ground around 350mA and at 5V that is 1.7W. This doesn't sound right to me but I am having trouble locating the information in the datasheet that tells me how much current is typically used by that IC.
I am using a resistor on the output clock because without it the lm7805 gets hotter faster.
Attached is a picture of my breadboard.
The LM7805's input is supplied by a 12V 500mA adapter.
The datasheet is found here : http://pdf1.alldatasheet.com/datasheet-pdf/view/17686/PHILIPS/HEF4017BP.html
Can anyone tell me where and or if I am going wrong about this?
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