Kev ua haujlwm PCBA ua tau raug faib ua ob pawg: DIP thiab SMD, DIP plug-in IC, thiab SMD (Ntu Mount Device) qhov chaw ntawm pob zeb saum toj.
Yog li, SMD 0603, dab tsi yog 0805, 1206?
Nws yog hais txog lub npov loj ntawm kev tivthaiv, thiab qhov ntev yog qhov ntev x dav. Chav tsev siv tau yog nti lossis hli. Feem ntau hais lus, kev tsis pom thiab kev peev xwm ntawm SMD yog txhua yam siv los piav txog qhov loj ntawm cov khoom. Ib tug lej ntawm 4 tug lej qha tas muaj 2 tug lej.
0603: 0.06 "x0.03", lossis 60x30 mils, los yog 1.6x0.8mm (Nco Ntsoov: 1mil = ib txhiab ib nti)
0805: 0.08 "x0.05", los yog 80x50 mils, los yog 2.0x1.25mm
1206: 0.12 "x0.06", los yog 120x60 mils, los yog 3.2 x 1.6mm
Qhov loj me thiab pawg neeg sib raug zoo:
| Pob | Dimensions, ntev × | Raug resistor kev ntsuam xyuas zog (W) | Lus tawm | ||
|---|---|---|---|---|---|
| Metric | Imperial | ||||
| 0402 | 01005 | 0.4 hli × 0.2 hli | 0.0157 nyob rau hauv × 0.0079 nyob rau hauv | 0.031 [9] | |
| 0603 | 0201 | 0.6 hli × 0.3 hli | 0.024 hauv × 0.012 nyob rau hauv | 0.05 [9] | |
| 1005 | 0402 | 1.0 hli × 0.5 hli | 0.039 hauv × 0.020 nyob rau hauv | 0.1, [9] lossis 0.062 [10] | |
| 1608 | 0603 | 1.6 hli × 0.8 hli | 0.063 nyob rau hauv × 0.031 nyob rau hauv | 0.1 [9] | |
| 2012 | 0805 | 2.0 hli × 1.25 hli | 0.079 nyob rau hauv × 0.049 nyob rau hauv | 0.125 [9] | |
| 2520 | 1008 | 2.5 hli × 2.0 mm | 0.098 nyob rau hauv × 0.079 nyob rau hauv | Qaug inductor thiab ferrite hlaws pob [11] | |
| 3216 | 1206 | 3.2 hli × 1.6 hli | 0.126 hauv × 0.063 nyob rau hauv | 0.25 [9] | |
| 3225 | 1210 | 3.2 hli × 2.5 hli | 0.126 hauv × 0.098 nyob rau hauv | 0.5 [9] | |
| 4516 | 1806 | 4.5 hli × 1.6 hli | 0.177 hauv × 0.063 hauv [12] | ||
| 4532 | 1812 | 4,5 hli × 3.2 hli | 0.18 nyob rau hauv × 0.13 nyob rau hauv | 0.75 [9] | |
| 4564 | Xyoo 1825 | 4.5 hli × 6.4 hli | 0.18 hauv × 0.25 nyob rau hauv | 0.75 [9] | |
| 5025 | Xyoo 2010 | 5.0 hli × 2.5 hli | 0.197 hauv × 0.098 nyob rau hauv | 0.75 [9] | |
| 6332 | 2512 | 6.3 hli × 3.2 hli | 0.25 nyob rau hauv × 0.13 nyob rau hauv | 1 [9] | |
| 2920 | 7.4 hli × 5.1 hli | 0.29 hauv × 0.20 hauv [13] | |||
Capacitor specification
Muaj ntau ntau hom kev lag luam, uas yog ua los ntawm ntau cov ntaub ntawv, xws li cov khoom siv hluav taws xob, cov tantalum capacitors, cov capacitors electrolytic, thiab lwm yam. 0, 1uF los yog ntau tshaj ntawd raug xam tias yog qhov tseem ceeb loj txaus. Cov tub lag luam loj loj muaj cov ncej zoo thiab tsis zoo (cov neeg paub txog cov peev xim)
Hais txog SMD capacitors, tsis zoo li resistors, nws tsuas pom ntawm cov specifications ntawm daim kab xev.
Hauv kev tso cai, txawm li cas los xij, los ntawm qhov ntim ntawm SMD capacitive, qhov loj dua qhov ntim, qhov loj dua qhov peev txheej.
Cov lus qhia hauv daim kab xev yuav pom tus nqi zoo ib yam li 104,103, qhov loj ntawm nws cov lus qhia txog kev ua lag luam. 104, tib yam li cov sawv cev saum toj no, 10 x 10 4 fais fab pF => 100000 pF = 100nF = 0.1uF. Zoo sib xws, 330 yog hais li 33pF.
Lwm yam khoom SMD
Transistor rau SMD, SOT (Small Outline Transistor), xws li SOT-23
Rau SMD tus IC, SOIC (Daim Ntawv Qhia Tiav Me (Small Outline IC), xws li SOIC-8, COV-16
Qhov ntau pins ntawm lub IC, qhov ntau dua ntim yees yuav muab tau los (uas yog, rooj plaub pob ntawm Tuag yuav txawv), piv txwv li
TQFP (Nyias Quad Plug Ncaws Pob), 100 lossis 144 pins.
PQFP (Plaub Plaub Plaub Plaub Plaub Hlis Plaub Ntug), 208 lossis 240 pins.
BGA (Pob-Daim phiaj Array), 256 mus rau 1000+ pins.