FootDrint is the meaning of the package .
Common components PCB package selection
Name Code Package Properties
Resistance RES1, RES2, RES3, RES4 AXIAL0.3-AXIAL0.7
Which refers to the resistance of 0.3, 0.7 length ( inch ) , usually with AXIAL0.4.
AXIAL translated into Chinese is shaft-shaped , 0.3 is the distance between the resistor pads of the printed circuit board is 300mil ( because the motor field, the English units are based ) .
For the circuit board is concerned, it simply is not associated with ohms , is based solely on the number of the resistance power to decide . We selected 1/4W or 1/2W resistor , can be used AXIAL0.3 component package , while a large number of words a little power available AXIAL0.4, AXIAL0.5 so .
SMD resistor package size and power related , generally speaking as follows :
0201 1/20W 0402 1/16W 0603 1/10W 0805 1/8W 1206 1/4W
Correspondence between chip capacitors and resistors package dimensions are:
0402 = 1.0mmx0.5mm 0603 = 1.6mmx0.8mm 0805 = 2.0mmx1.2mm
1206 = 3.2mmx1.6mm 1210 = 3.2mmx2.5mm 1812 = 4.5mmx3.2mm
2225 = 5.6mmx6.5mm
Of which : 0.04 × 25.4 = 1.016mm, 0.02 × 25.4 = 0.508mm
Promise of capacitor cap RAD0.1 to RAD 0.4
Which refers to the size of the capacitor 0.1-0.3 (Inch ) , generally with RAD0.1
Electrolytic capacitor electroi RB.2/.4 to RB.5/1.0
Which means .1/.2-.4/.8 capacitor size . Wherein " .4" pad spacing " .8" outer diameter of the cylindrical capacitor .
General <100uF with RB.1/.2, 100uF-470uF with RB.2/.4, 470uF with RB.3/.6.
Potentiometer pot1, pot2 vr1 to vr5
Diodes DIODE0.4-DIODE0.7 diode0.4 ( low power ) diode0.7 ( power )
Which refers to the diode 0.4-0.7 length , usually with DIODE0.4, light-emitting diodes with RB.1/.2
Transistor, FET to-18 ( ordinary transistor ) to-22 ( power transistor ) to-3 ( high power Darlington )
For the transistor , then a direct look at its shape and power , high-power transistors , on the use of TO-3, medium power transistors , if it is flat, on the use of TO-220, if it is metal shell , use TO- 66 , low-power transistors , on the use of TO-5, TO-46, TO-92A and so can , anyway it 's pins and long , curved look also .
Power regulator block 78 and 79 series 7805,7812,7820,7905,7912,7920 common package has to126h and to126v
Rectifier bridge BRIDGE1, BRIDGE2 D series (D-44, D-37, D-46)
Crystal CRYSTAL / XTAL1 XTAL1
Dual Inline element DIP8-DIP40, for conventional integrated circuit IC , there DIPxx, is the element of dual in-line package , DIP8 is double , each row has four pins, the distance between two rows is 300mil, pads the distance between the 100mil. SIPxx is a single row of package.
