I have a project to build heating element using silver ink.
My specification is the heating element must be in range 2 to 2.6ohm
I will design the circuit for the heating element, but have a problem
how to theoretically measure the resistance of the circuit(before send to print house).
Based on reference on this website
http://circuitcalculator.com/wordpress/2006/06/14/conductive-ink-traces/
the resistance can be measure as below
Resistance = Sheet_Resistivity*(Length/Width)*(Ref_Thickness/Thickness)
In my case,
Sheet Resistivity = 10miliohms/square,
Ref_Thickness = 1mil(0.025mm)
Thickness = 1mil(0.025mm)
1) Based on the quotation, if I have 50mm x 50mm & another one is 10mm x 10mm
silver ink with same thickness, the ohm will be the same which is 10miliohms.
Is it logic?
2) Another question is, how to measure the resistance if I design a complicated
circuit as per attached image? In the image, 1box considered as 1mm x 1mm
Point "A" and point "B" will be connected to battery(+ve & -ve).
Blue color indicate the silver ink
Your advice and explanation will be very helpfull. Thank you.
Best Answer
As well as Ignacio's answer on the straight bits, you can consult "Handbook of Electronic Package Design, By Michael Pecht" which has formulas used for correcting for the corner geometry when you use a serpentine (meander) pattern.