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Resistors. HAND SOLDERING AND CIRCUIT BOARD REPAIR (EECE1100) Spring 2009 Continuing Education Program, Conestoga College Dr. Monzur Kabir, P. Eng. Professor, Applied Degree Program of Integrated Telecom and Computer Technology (ITCT) Conestoga College. Resistors on PCB. Resistors
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Resistors HAND SOLDERING AND CIRCUIT BOARD REPAIR (EECE1100) Spring 2009 Continuing Education Program, Conestoga College Dr. Monzur Kabir, P. Eng. Professor, Applied Degree Program of Integrated Telecom and Computer Technology (ITCT) Conestoga College
Resistors on PCB Resistors (axial components with color bands
Resistor Color Code http://www.educypedia.be/electronics/resistorcolorcode.gif Note: A resistor with a single black-band is a zero ohm resistor 3
Resistor Color Code PPM = Part per million http://www.oilfield.de/download/techtabs/electron/ccode001.pdf 4
Resistor Color Code – Online Tools • Color to Value (with Tolerance): • http://www.electronics-lab.com/articles/basics/resist/index.html?result=350 Value with (Tolerance) to Color: http://www.ealnet.com/m-eal/resistor/resistor.htm 5
Standard Resistor Values • Electronic Industries Association (EIA) standard E24: • Standard E24 specifies resistors based on 5% tolerance (often resistor of this category has 2% tolerance now a days due to advancement of manufacturing techniques) Standard Resistor values = × 10MOhms (Where M can be any integer, positive or negative) For other standards:http://www.logwell.com/tech/components/resistor_values.html
Resistor with Different Power Ratings Examples: 2 Watts 1 Watt 1 Watt 0.5 Watt 0.25 Watt 0.25 Watt The size indicates the power rating, NOT the resistance value
Resistor Examples Source: Basic Electronics, Bernard Grob Through-hole Resistors SMT Components http://www.wordiq.com/definition/Resistor (Larger size often indicates higher power rating)
Resistor Code Ref: http://www.lalena.com/audio/electronics/color/ • SIL (Single In-Line) network: • The 4 and 7 are significant digits and the 3 is the decade, giving 47 x 1000 or 47 KW • The letter after the numbers is the tolerance. The different representations are: M=±20%, K=±10%, J=±5%, G=±2%, F=±1%. • Detail Spec: http://www.vishay.com/docs/31509/csc.pdf • SMD (Surface Mount Device): • The 1 and 0 are significant digits and 3 is the decade, giving 10 x 1000 or 10 KW • Direct Value: • Resistors with larger physical size are often printed the value directly on their body
Resistor Specifications Value: Ohms (W) Tolerance: % of Ohmic value Safety Rating: Power in Watt Shape: Axial (mostly) Technology: Through-hole or SMD (Surface Mount Device)