Dab tsi yog qhov kev xav tsis zoo yuav tsum zam thaum yuav khoom diodes?

Ib, Qauv thiab ntim tsis meej pem: cov ntsiab lus txiav txim siab ua tiav lossis tsis ua tiav
1. Ntau pob ntxiab ntawm tib tus qauv
Lub ntsiab lus ntawm tus qauv diode feem ntau muaj cov ntaub ntawv ntim, tab sis tej zaum yuav muaj ntau daim ntawv ntim rau tib tus qauv. Piv txwv li, 1N4148 diode muaj ntau tshaj kaum hom pob khoom, suav nrog DO-35 (axial iav pob), SOD-123 (patch me me), SOT-23 (peb tus pin thaj), thiab lwm yam.

Case: Ib qho hluav taws xob tsheb tiv thaiv- qhov project tub sab nyiag tau raug yuam kom rov tsim kho PCB vim qhov chaw tsis txaus ntawm lub rooj tsav xwm hluav taws xob los ntawm kev yuav khoom yuam kev 1N4148 ntim hauv SOD-123, ua rau kev xa khoom qeeb thiab nce nqi.

Avoidance Strategy:

Xav kom cov neeg muag khoom muab cov qauv thiab ntim cov lus sib piv, qhia meej txog qhov tsis sib xws (xws li qhov ntev, qhov dav, qhov siab, qhov sib txawv ntawm tus pin).
Ua 3D qauv kev txheeb xyuas ntawm cov khoom tseem ceeb kom ntseeg tau tias kev sib raug zoo nrog PCB layout.
2. Tsis meej pem ntawm nruab nrab lub cev / lub cev nqaim / dav lub cev
Qhov dav ntawm diode ntim ncaj qha cuam tshuam rau cov cua sov dissipation thiab txhua yam muaj zog. Tus qauv JEDEC txhais cov SOIC pob dav li 3.9 hli (lub cev nqaim) lossis 7.5 hli (lub cev dav), thaum EIAJ tus qauv SOP pob dav yog 5.3 hli. Yog tias tus qauv tsim yuav tsum muaj lub cev dav dav tab sis ua yuam kev yuav lub cev nqaim, nws yuav ua rau cov khoom siv overheating lossis tsis zoo soldering.

Case: Lub hwj chim module tau ntsib kev sib koom tes sib koom ua ke nyob rau hauv qhov siab - qhov kub thiab txias vim yog kev siv tsis raug ntawm 3.9mm dav SOIC-8 ntim diodes, ua rau batch rework.

Avoidance Strategy:

Qhia meej txog cov qauv ntim khoom (xws li JEDEC / EIAJ) thiab qhov ntev tshwj xeeb hauv BOM rooj.
Thov tus neeg muag khoom muab cov duab lossis 3D qauv ntawm cov khoom ntim rau kev pom zoo thib ob.
2, Parameter misjudgment: dual txaus ntshai ntawm kev ua tau zoo thiab kev ruaj ntseg
1. Tsis txaus thim rov qab tiv thaiv qhov hluav taws xob
Qhov rov qab tiv thaiv hluav taws xob (VRRM) ntawm diodes yuav tsum muaj cov npoo ntawm 20% -30% txhawm rau tiv thaiv qhov hloov pauv voltage. Yog tias tsuas yog xaiv qhov nominal voltage, nws tuaj yeem ua rau tawg vim qhov kev hloov pauv dhau sijhawm.

Case: Ib qho hluav taws xob tsheb tiv thaiv- tub sab tub nyiag qhov project siv SS24 Schottky diode (nominal thim rov qab tiv thaiv hluav taws xob 40V), uas ua rau cov khoom tawg thiab cov cuab yeej tswj tsis tau vim qhov hloov pauv ntawm qhov hluav taws xob hauv 60V.

Avoidance Strategy:

Xaiv cov khoom nrog rov qab tiv thaiv voltage Ntau dua los yog sib npaug rau 1.3 × VIN_max raws li qhov siab tshaj plaws input voltage (VIN_max) ntawm Circuit Court.
Rau kev siv hluav taws xob dav dav (xws li 48V / 60V tau tshaj lub tshuab), qhov tseem ceeb yuav tsum tau muab rau kev siv cov qauv hluav taws xob tiv taus siab tshaj 80V.
2. Forward tam sim no thiab thermal tsim tsis sib xws
Qhov nruab nrab tam sim no rau pem hauv ntej (IF (AV)) ntawm lub diode yuav tsum tau sib phim nrog cov cua kub dissipation. Yog tias qhov thermal tsis kam (R θ JA) thiab ambient kub tsis quav ntsej, nws yuav ua rau cov khoom ua kom sov thiab hlawv.

Case: Ib qho kev hloov hluav taws xob hloov hluav taws xob tau xaiv 1N5819 Schottky diode (IF (AV)=1A), tab sis vim tsis muaj qhov cua sov hauv cheeb tsam, qhov kev khiav hauj lwm tam sim no tau dhau tus qauv thaum nws tsuas yog 0.5A.

Avoidance Strategy:

Xam cov kev siv hluav taws xob tiag tiag: P=Vf × Yog (Vf yog qhov kev poob qis rau pem hauv ntej, Yog tias yog qhov ua haujlwm tam sim no).
Xaiv cov ntim khoom lossis ntxiv cov ntsuas cua sov (xws li cov ntaub ntawv thermal, cov dab dej kub) raws li qhov ntsuas kub tsis kam.
3. Tsis saib xyuas lub sijhawm rov qab los
High zaus hloov circuits (xws li DC-DC converters) yuav tsum tau siv cov diodes nrog luv luv rov qab lub sij hawm (trr). Yog tias cov raj rectifier zoo tib yam siv tsis raug, nws tuaj yeem ua rau muaj kev hloov pauv loj.

Case: Ib lub voj voog Buck siv 1N4007 rectifier diode (trr=300ns) nrog kev ua haujlwm ntawm tsuas yog 82%. Tom qab hloov mus rau UF4007 ceev rov qab diode (trr=50ns), qhov ua tau zoo tau nce mus rau 88%.

Avoidance Strategy:

Thaum qhov hloov pauv zaus ntau dua 100kHz, Schottky diodes (trr<10ns) or fast recovery diodes (trr<50ns) are preferred.
Xa mus rau TRR zaus kev sib raug zoo nkhaus hauv cov ntaub ntawv phau ntawv rau kev xaiv.
3, Kev Tswj Xyuas Kev Lag Luam thiab Kev Pabcuam: Kev Tiv Thaiv Kev Tiv Thaiv thiab Tswj
1. Ntau hom kev sib raug zoo cuab
Tib hom diode tej zaum yuav tsim los ntawm ntau hom, tab sis tej zaum yuav muaj qhov sib txawv ntawm qhov tsis sib xws. Piv txwv li, muaj cov hom xws li ST, NXP, ON rau 74HC14d siab -ceev CMOS ntaus ntawv, thiab lawv qhov pib voltage thiab kis tau tus mob ncua yuav txawv.

Case: Ib txoj haujlwm kho mob tau ua rau lub sijhawm teeb tsa tsis zoo vim yog sib xyaw hom sib txawv ntawm 74HC14d, yuav tsum tau rov ua dua ntawm lub voj voog.

Avoidance Strategy:

Kom meej meej qhia lub hom nyob rau hauv lub rooj BOM los yog muab ib daim ntawv teev cov lwm hom.
Xav kom cov neeg muag khoom muab cov lus qhia sib xws kom tsis txhob sib xyaw ua ke.
2. Cov ntaub ntawv txias thiab raug kaw
Qee lub diodes tab tom ntsib kev lag luam nres vim kev lag luam cog lus lossis kev siv thev naus laus zis. Yog tias kev hloov pauv tsis raug ntsuas ua ntej, nws tuaj yeem ua rau muaj kev cuam tshuam ntawm kev tsim khoom loj.

Case: Ib qho kev tswj hwm kev lag luam tau raug yuam kom hloov mus rau lwm tus qauv tom qab lub Hoobkas thawj zaug tso tseg vim qhov tsis ua tiav ntawm TL431 voltage regulator diode ua ntej, thiab kev ua haujlwm hauv Circuit Court yuav tsum tau ntawv pov thawj.

Avoidance Strategy:

Ua qhov kev ntsuas lub neej ntawm cov khoom tseem ceeb thiab ua qhov tseem ceeb ntawm kev siv cov khoom lag luam tseem ceeb lossis ntev - qauv kev ua neej.
Tsim kom muaj qhov chaw muab khoom thib ob kom muaj kev sib txawv ntawm cov khoom lag luam txaus ntshai.
4, Kev Txhim Kho ntawm Cov Txheej Txheem Kev Muag Khoom: Los ntawm Kev Paub Txog Kev Tswj Xyuas Txheej Txheem
1. Standardization ntawm BOM rooj
Kom meej meej sau cov ntaub ntawv tseem ceeb xws li qauv, ntim, hom, parameter margin, thiab lwm yam.
Piv txwv:
1N4148WS-SOD-123-NXP-VRRM Ntau dua lossis sib npaug rau 75V-IF(AV) Ntau dua lossis sib npaug rau 200mA
2. Kev sib koom tes ntawm cov neeg siv khoom
Xav kom cov neeg muab khoom siv los muab cov ntaub ntawv phau ntawv, cov ntaub ntawv xeem, thiab cov qauv kuaj xyuas.
Ua ntawm -kev tshuaj xyuas qhov chaw ntawm cov chaw muag khoom tshiab los ntsuas lawv cov kev tswj xyuas cov khoom muag thiab kev tswj xyuas kom zoo.
3. Kev siv cov cuab yeej digital
Siv cov ntaub ntawv tivthaiv xws li Octopart thiab Digi Key rau kev sib piv parameter.
Kev xa tawm ERP system kom ua tiav cov txheej txheem kev yuav khoom thiab zam kev ua yuam kev ntawm tib neeg.