SMT零件識(shí)別
一 電阻(Resistor):
SMT 電阻一般而言, 其常用之外型尺寸有以下數(shù)種規(guī)格:
Generally, the SMT resistor dimension of common using is following 3 types:
|
項(xiàng)目
(Item)
|
尺 寸 ( Dimension)
|
|
|
公制(mm)
|
英制(inch)
|
|
|
1
|
1.6mmx0.8mm(1608) | 0.06in.x0.03in.(0603) |
|
2
|
2.0mmx1.25mm(2125) | 0.08in.x0.05in.(0805) |
|
3
|
3.2mmx1.6mm(3216) | 0.12in.x0.06in.(1206) |
注:公制與英制間之單位換算會(huì)有些許誤差, 且各家廠商之產(chǎn)品間亦有少許差異, 因此上述之尺寸數(shù)據(jù)為概略值。There will be little of bias when we converse mm to inch. Different vendor will make little of dimension. Above table is estimate dimension.
SMT 電阻的阻值可直接由電阻上之?dāng)?shù)字計(jì)算出來:
The resistor value can be read by marking on resistor surface:
(1) 一般電阻: 其阻值以3碼標(biāo)示。單位為奧姆(ohm; Ω), 以下為例:
Normal resistor: Using 3 digital to represent resistor value:
*若電阻標(biāo)示為203, 則其阻值之計(jì)算方式為
If the digital is “203”, then the resistor value is:
20x103 = 20000 ohm = 20K ohm
*若電阻標(biāo)示為351, 則其阻值之計(jì)算方式為
If the digital is “351”, then the resistor value is:
35x101 = 35 ohm
*若電阻標(biāo)示為050, 則其阻值之計(jì)算方式為
If the digital is “050”, then the resistor value is:
05x100 = 5 ohm
(2)精密電阻: 其阻值以4碼標(biāo)示。單位為奧姆(ohm; Ω), 以下為例:
Precise resistor: Using 4 digital to represent resistor value:
若電阻標(biāo)示為1203, 則其阻值之計(jì)算方式為:
If the digital is “1203”, then the resistor value is:
120x103 = 120000 ohm = 120K ohm
若電阻標(biāo)示為1301, 則其阻值之計(jì)算方式為:
If the digital is “1301”, then the resistor value is:
130x101 = 130 ohm
若電阻標(biāo)示為0500, 則其阻值之計(jì)算方式為:
If the digital is “0050”, then the resistor value is:
050x100 = 50 ohm
(3) 0 奧姆電阻, 其阻值之標(biāo)示為0:
0 ohm is represented as below:
(4) 電阻標(biāo)示中若有”R”, 表示阻值中有小數(shù)點(diǎn):
Letter “R” means dot as below:
5R6 = 5.6 ohm
二 電容 (Capacitor):
SMT 電容之外型尺寸與電阻相同, 常用之外型尺寸有以下數(shù)種規(guī)格:
SMT capacitor dimension is same as resistor, the dimension of common using is as below:
|
項(xiàng)目
(Item)
|
尺 寸 (Dimension)
|
|
|
公制(mm)
|
英制(inch)
|
|
|
1
|
1.6mmx0.8mm(1608) | 0.06in.x0.03in.(0603) |
|
2
|
2.0mmx1.25mm(2125) | 0.08in.x0.05in.(0805) |
|
3
|
3.2mmx1.6mm(3216) | 0.12in.x0.06in.(1206) |
SMT 電容在外觀上無法辨別其電容值, 需以電容表量測(cè)。
Capacity value can’t show on the capacitor surface, it should be measured by meter.
三 IC:
(1) 名詞解釋(Definition):
Pin: IC 腳 (又稱lead)。
Pin: IC lead.
Pitch: Pin的中心點(diǎn)到相鄰Pin的中心點(diǎn)之距離。
Pitch: Distance between pin center to next pin center.
(2) 外觀分類(IC package type):
2.1 SOP(Small Outline Package): IC腳位于本體兩側(cè), 呈L型向外延伸。
SOP(Small Outline Package): IC leads are L-shape and locate in 2 side of body.
