Demystifying Reverse Recovery na MOSFET Body Diodes

N'ebe eletrọnịkị, MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistor) apụtala dị ka ihe mejupụtara ebe niile, nke a ma ama maka ịrụ ọrụ nke ọma, ngbanwe ọsọ na njikwa. Agbanyeghị, njirimara ebumpụta ụwa nke MOSFET, diode ahụ, na-ewebata ihe a maara dị ka mgbake azụ, nke nwere ike imetụta arụmọrụ ngwaọrụ yana imewe sekit. Bọọgụ blọgụ a na-abanye n'ime ụwa nke mgbake na MOSFET ahụ diodes, na-enyocha usoro ya, ihe ọ pụtara, yana ihe ọ pụtara maka ngwa MOSFET.

Na-ekpughe usoro nke mgbake mgbake

Mgbe agbanyụrụ MOSFET, a na-akwụsịtụ ọwa ya ugbu a na mberede. Otú ọ dị, parasitic ahụ diode, nke a kpụrụ site na nhazi nke MOSFET, na-eme mgbanwe mgbanwe ugbu a ka ụgwọ echekwara na ọwa na-ejikọta. Nke a na-atụgharị ugbu a, nke a maara dị ka azụghachi azụ azụ (Irrm), ji nwayọọ nwayọọ na-ere ure ka oge na-aga ruo mgbe ọ ruru efu, na-akara njedebe nke oge mgbake azụ (trr).

Ihe na-emetụta mgbake mgbake

Njirimara mgbake nke MOSFET diodes nwere ọtụtụ ihe na-emetụta ya:

Structure MOSFET: Geometry, ọkwa doping, na ihe onwunwe nke nhazi ime MOSFET na-ekere òkè dị ukwuu n'ịchọpụta Irrm na trr.

Ọnọdụ ọrụ: A na-emetụtakwa omume mgbake azụ site na ọnọdụ arụ ọrụ, dị ka voltaji etinyere, ngbanwe ọsọ na okpomọkụ.

Mpụga Circuit: Mpụga sekit ejikọrọ na MOSFET nwere ike imetụta usoro mgbake azụ, gụnyere ọnụnọ nke sekit snubber ma ọ bụ ibu inductive.

Mmetụta nke mgbake mgbake maka ngwa MOSFET

Mweghachi azụ nwere ike iwebata ọtụtụ ihe ịma aka na ngwa MOSFET:

Voltaji spikes: Mbelata mberede nke mgbanwe mgbanwe ugbu a n'oge mgbake azụ nwere ike iwepụta spikes voltaji nwere ike gafere voltaji ndakpọ MOSFET, nwere ike imebi ngwaọrụ ahụ.

Ọnwụ ike: Mweghachi mgbake ugbu a na-achụsasị ume, na-eduga na mfu ọkụ na nsogbu ikpo ọkụ.

Mkpọtụ Circuit: Usoro mgbake azụ nwere ike ịgbanye mkpọtụ n'ime sekit, na-emetụta iguzosi ike n'ezi ihe mgbaàmà ma nwee ike ịkpata mmebi na sekit nwere mmetụta.

Mbelata Mmetụta mgbake

Iji belata mmetụta ọjọọ nke mgbake azụ, enwere ike iji ọtụtụ usoro:

Snubber circuits: Snubber sekit, nke na-agụnye resistors na capacitors, nwere ike jikọọ na MOSFET iji belata spikes voltaji ma belata mfu ume n'oge mgbake.

Usoro ngbanwe dị nro: Usoro ngbanwe dị nro, dị ka pulse-width modulation (PWM) ma ọ bụ mgbanwe resonant, nwere ike ijikwa ngbanwe nke MOSFET nke nta nke nta, na-ebelata ogo mgbake azụ.

Ịhọrọ MOSFET nwere mgbake dị ala: MOSFET nwere obere Irrm na trr nwere ike ịbelata mmetụta nke mgbake mgbake na arụmọrụ sekit.

Mmechi

Mweghachi azụ na MOSFET diodes ahụ bụ ihe e ji mara nke nwere ike imetụta arụmọrụ ngwaọrụ yana imewe sekit. Ịghọta usoro ahụ, ihe ndị na-emetụta, na ihe mgbake mgbake dị oke mkpa maka ịhọrọ MOSFET kwesịrị ekwesị na iji usoro mbelata iji hụ na arụmọrụ sekit kacha mma na ntụkwasị obi. Ka MOSFET na-aga n'ihu na-arụ ọrụ dị mkpa na sistemu eletrọnịkị, ịgbasa mgbake mgbake ka bụ akụkụ dị mkpa nke imewe sekit na nhọrọ ngwaọrụ.