Based on a limited amount of empirical data over a 10C to 75C range
of heat rise
the equations for a polyimide flex circuit constructed with 1 oz / 1
mil 
laminate and 1 mil coverfilm are:


Current = ( 0.7175 dT + 33.169 ) x TA

dT = ( 1.398 Current / TA ) - 46.384

TA = Current / ( 0.7151 dT + 33.169)


Where:
Current = Current capacity rating in Amps
dT = Change in temperature in C
TA = Cross section area of traces in sq.mm.



     
     Andy Magee - Applications Engineer
     Rogers - Circuit Materials
     Tel: (602) 917-5237
     Fax: (602) 917-5256
     E-Mail: [log in to unmask]
     Website: http//www.rogers-corp.com/cmu
     
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