Yuav ua li cas tiv thaiv cov tiam ntawm switching fais fab mov ripple
Nrog rau kev hloov ntawm SWITCH, tam sim no hauv inductor L kuj hloov pauv nce thiab nqis ntawm tus nqi zoo ntawm cov zis tam sim no. Yog li ib qho ripple nrog tib zaus li SWITCH tseem yuav tshwm sim ntawm qhov kawg tso zis, uas feem ntau hu ua ripple. Nws muaj feem xyuam rau lub peev xwm ntawm cov zis capacitor thiab ESR.
Yuav ua li cas rau suppress lub tiam ntawm switching fais fab mov ripple? Peb lub hom phiaj yog kom txo tau cov zis ripple mus rau theem siab, thiab cov kev daws teeb meem tseem ceeb tshaj plaws kom ua tiav lub hom phiaj no yog:
Cov tiam ntawm Ripples hauv Switching Fais Fab Khoom
Peb lub hom phiaj yog kom txo cov zis ripple mus rau theem siab, thiab cov kev daws teeb meem tseem ceeb kom ua tiav lub hom phiaj no yog kom tsis txhob muaj lub cim ntawm ripple ntau li ntau tau. Ua ntej, peb yuav tsum tau qhia meej txog hom thiab ua rau ntawm kev hloov fais fab mov ripple.
Nrog rau kev hloov ntawm SWITCH, tam sim no hauv inductor L kuj hloov pauv nce thiab nqis ntawm tus nqi zoo ntawm cov zis tam sim no. Yog li ib qho ripple nrog tib zaus li SWITCH tseem yuav tshwm sim ntawm qhov kawg tso zis, uas feem ntau hu ua ripple. Nws muaj feem xyuam rau lub peev xwm ntawm cov zis capacitor thiab ESR. Qhov zaus ntawm qhov ripple no zoo ib yam li qhov hloov pauv hluav taws xob, xws li kaum mus rau ntau pua KHz.
Tsis tas li ntawd, lub Bipolar junction transistor lossis MOSFET feem ntau yog xaiv los ua qhov hloov. Tsis muaj teeb meem twg yog qhov hloov pauv, yuav muaj lub sijhawm nce thiab lub caij nplooj zeeg thaum nws qhib thiab tawm. Lub sijhawm no, lub suab nrov nrog tib zaus lossis khib ntau zaus thaum lub sijhawm nce thiab poob ntawm SWITCH yuav tshwm sim hauv Circuit Court, uas feem ntau yog kaum ntawm MHz. Ib yam li ntawd, thaum lub sijhawm rov qab los, qhov sib npaug ntawm lub diode D yog kev sib txuas ntawm cov resistors, capacitors, thiab inductors, uas tuaj yeem ua rau resonance thiab tsim suab nrov zaus ntawm kaum ntawm MHz. Ob hom suab nrov no feem ntau hu ua lub suab nrov nrov, thiab lawv qhov amplitude feem ntau loj dua qhov ripple.
Yog tias nws yog AC / DC converter, ntxiv rau ob hom ripple (suab nrov) hais los saum no, kuj tseem muaj AC suab nrov. Qhov zaus yog qhov zaus ntawm cov khoom siv AC lub zog, uas nyob ib puag ncig 50-60Hz. Kuj tseem muaj cov suab nrov nrov uas tshwm sim los ntawm qhov sib npaug ntawm cov khoom siv hluav taws xob tsim los ntawm kev siv cov ntaub thaiv npog raws li cov dab dej kub hauv ntau lub zog ntawm cov khoom siv hluav taws xob hloov. Raws li kuv tau koom nrog hauv kev tshawb fawb thiab kev tsim kho tsheb hluav taws xob, kuv tsis xav txog ob hom suab nrov tom qab vim kuv qhov raug txwv.
Kev ntsuas ntawm Switching Power Supply Ripple
Cov kev cai yooj yim: siv oscilloscope AC coupling, 20MHz Bandwidth throttling, thiab unplug lub sojntsuam av hlau
1. AC coupling yog tshem tawm cov superimposed DC voltage thiab tau txais qhov tseeb waveform.
2. Tig rau 20MHz Bandwidth throttling kom tsis txhob muaj lub suab nrov nrov cuam tshuam thiab sim ua yuam kev. Vim qhov loj amplitude ntawm high-frequency Cheebtsam, lawv yuav tsum tau muab tshem tawm thaum lub sij hawm ntsuas.
3. Unplug grounding clamp ntawm oscilloscope sojntsuam thiab siv lub nplhaib grounding rau kev ntsuas los txo kev cuam tshuam. Ntau qhov chaw tsis muaj lub nplhaib hauv av, thiab yog tias qhov yuam kev raug tso cai, nws tuaj yeem ntsuas ncaj qha los ntawm kev siv lub hauv paus clamp ntawm kev sojntsuam. Tab sis qhov tseem ceeb no yuav tsum tau xav txog thaum txiav txim siab seb nws puas tsim nyog.
Lwm qhov taw qhia yog siv lub davhlau ya nyob twg 50 Ω. Raws li tau hais hauv Yokogawa oscilloscope cov ntaub ntawv, 50
