Post by thread:[EE]: Determine 1206/0805 capacitor value

>> Is there a standard color code of numbering system used for chip capacitors? No. Pisses me off, too. They print values on resistors that are the same size; and resistors are easier to measure :-( BillW -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

William Chops Westfield wrote: > > >> Is there a standard color code of numbering system used for chip capacitors? > > No. > > Pisses me off, too. They print values on resistors that are the same > size; and resistors are easier to measure :-( Measure it in circuit. Generally most capacitance meters use a high(ish) frequency and the rest of the circuit is isolated from caps via RC time constants. You can measure a cap value prob within 10% or 20% higher than actual, usually good enough to tell you what it is. One exception is chip decoupling caps that tend to be paralleled on psu rails. -Roman -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

Some lucky few do have a numbering system on them. The numbering like 105 means 0.000001 uF (ie, last digits are the number of 0's berore the first number. KreAture {Original Message removed}

Isn't it 1.000.000 pF (1 uF) ? That is "10" with 5 zeros, much like the resistor system ? That would be easier to "read" anyway... "103" = 10nF"103" = 10nF"102" = 1nF "101" = 100pF And so on. Jan-Erik Söderholm. {Original Message removed}

> Some lucky few do have a numbering system on them. > The numbering like 105 means 0.000001 uF (ie, last digits are the number of > 0's berore the first number. I seriously doubt that unless you can show me a data sheet that says this explicitly. All such three digit numbers I've seen (and I strongly suspect yours too) are a floating point representation for the capacitance in picofarads. The first two digits are the mantissa, with the third being the exponent of 10. Therefore "105" means 10 x 10**5 pF = 1,000,000pF = 1uF. ***************************************************************** Embed Inc, embedded system specialists in Littleton Massachusetts (978) 742-9014, http://www.embedinc.com -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads