Fast restore diode structure characteristic

 

Fast the interior construction that resumes diode and common diode are different, it is to be in P, increased among N silicon material base area I, make P-I-N silicon chip. As a result of base the area is very small, carry on one’s shoulder of retrorse extensive telegram in reply is very small, reduced Trr cost greatly not only, still reduced transient state to pressure fall, make pipe can bear very tall retrorse job voltage.

 

Fast restore time what restore diode to be second of hundreds of accept commonly reversely, to pressure fall to be 0.6V about, to electric current it is a few reach thousands of, voltage of retrorse peak value can be amounted to hundreds of to thousands of bend over. Super- fast restore charge what restore diode to be reduced further reversely, make its Trr but low to second of a few accept. Under 20A fast restore to reach super- fast restore diode to use TO-220 to enclose a form mostly. Look from internal composition, can divide into sheet canal, right canal (also weigh double-barreled) two kinds. Restore diode quickly to be in charge of interior to include two, what receive a standard according to two diode is different, have again in all shade is right canal, in all this world cent to the canal. Graph 2(a) is C20-04 model fast restore diode (single pipe) appearance and internal composition. (B) pursues and (C) graph is C92-02 respectively model (in all shade is right canal) , MUR1680A (in all this world is right canal) exceed fast the shell that restores diode and construction. They all use TO-220 plastic enclose, a few those who install is fast restore diode to use TO-3P metal carapace to enclose commonly. More high capacity (hundreds of install ～ thousands of how) pipe uses bolt model or flat enclose a form.

 

Fast restore diode note (1) a little single pipe, in all 3 cite a base, among for empty foot, cut off when leave factory commonly, but also have what do not cut. (2) there is a pipe to damage in be like pair of canals, can use as single pipe. (3) measure guide is connected pressure when falling, must use R×1 file. If use R×1k file, because test electric current is too small, far the regular job electric current under pipe, reason measures the VF that go out to be worth will apparent on the low side. Above in example, if choose R×1k archives to measure, be equal to 2.2kΩ to resistor, right now N′=9 case. Calculate from this computational VF is worth only 0.27V, far under normal value (0.6V) .

 

The 4 big application that TVS provides (1) TVS is in charge of the applied thunder overvoltage in system of TN power source the overvoltage that the factitious operation mistake such as wave, laden switch causes passes power supply circuitry easily to invade interior of electric electron equipment, cause lose effectiveness of electric electron device, misoperation, cause the permanent damage of equipment even, cause severe pecuniary loss. Absorb device MOV and TVS through surge is being installed on road of power supply cord, carry out two class protection, undertake to line of L, N in all protection of model, wrong standard.

 

The front that particular way is online road installs MOV to regard SPD of the first class as protection, lightning current of discharge enlarge part, the extreme of online road (equipment front) canal of installation high-power TVS is protected as SPD of the 2nd class, weaken overvoltage wave amplitude further, reach voltage drop of electrified wire netting in limits of E/I safe compression. Those who want an attention is, the harmony that MOV and TVS should achieve voltage and energy and cooperate, the circuit length between AB should not be less than 5 M, should increase circuit length otherwise or install the parts of an apparatus that retreat Ou.

(2) the surge that TVS is in charge of the applied TVS canal in network signal circuitry to be able to be used at power source system not only defends, return the surge that can be used at line means to protect, use GDT of gas discharge tube and TVS canal combination to become signal surge protector, its characteristic is reaction fast, leakage shedding is small, do not have loss to signal almost, can provide safe, reliable protection to circuitry of high speed network.

 

(3) TVS is in charge of the circuit of uses computer of a common PC power supply source in system of direct current source, step-down of transformer of course of AC 220 V reachs town report AC 20 V, work galvanic way via modulation again, output direct current source of DC 10 V, receive load. Install voltage of two-way transient state to restrain through end is being outputted in transformer implement TVS1, absorb the electric current of instantaneous shock pulse of L and N line, bringing circuit voltage strangulation full voltage level, TVS1 can protect circuit of etc of commutator of transformer back end yuan parts of an apparatus. The end of output of direct current source after rectifier installs voltage of one-way transient state to restrain implement TVS2, use at protecting dc load to avoid to suffer overvoltage report electric current to pound.

 

(4) the applied crystal dynatron of body canal circuit regards TVS Guan Zaijing as voltaic control parts of an apparatus, it is the main component in electronic integrated circuit, can divide for NPN canal and PNP are in charge of two kinds, apply at switch circuit, enlarge circuit and stabilized voltage circuit. Suffer ESD/EFT to make transistor circuit is avoided (electrostatic discharge / report is fast twinkling changes pulse group) the interference that waits for surge voltage, be carried in the input of circuit and output end to join TVS1, TVS2 to undertake protective respectively.

 

 

Fast the distinction that restores diode and TVS is sharp the component that restoring diode and Tvs canal can not be two completely different property, absolutely not OK crossing-over. TVS is the instant controls protective element too, cannot bear labour frequency electric current, can use in pressing protective circuit too for an instant only. Fast restore diode to be used in high frequency the place that waits for wave of circuit commutate filter, pressure fall small, rate is rapid, calorific amount is small also, circuit of switch power source is for instance medium. Transient state voltage is restrained implement (TVS) it is to use those who eliminate voltage pointed pulse, protective report is service, receive for instance use in data interface prevent be struck by lightning, voltage wave motion.

 

TVS often uses as voltage clamp use like stabilized voltage diode, just its can susceptive instant power is very great, if 1.5KE200 can bear the power of instantaneous 1.5KW, the job should be on the principle at squeezing accept puncture; (Exceed) the refreshment that what restore a canal to tell quickly is cavity of the electron when diode works speed, general job at just as bias voltage, often apply at the circumstance of high frequency signal such as commutate of switch power source, be like FR107, 4148, f4007 is to restore a canal quickly (restore time not to exceed 150ns reversely usually; 4148 call switch diode again, restore time because of it reversely only very carry —— to have 4ns) only; There still is one additionally to plant in commutate of switch power source the most commonly used, be called “ a bit special base the diode that is in charge of ” , this kind of pipe is nonexistent the problem of electronic cavity, nonexistent also restore time reversely.

 

TVS diode and fast restoring diode is to use stabilized voltage in circuit, but working mechanism is different. TVS diode is one kind is pressed quick diode, the resistance that the change that is the upright voltage according to it will come change it achieves stabilized voltage effect. Fast restoring diode is diode of a kind of neat accept, namely diode of “ avalanche ” , when its upright voltage exceeds its threshold values, the retrorse resistance that PN writtens guarantee puncture will change it will achieve stabilized voltage effect. Both working mechanism differs completely, receive a law to also differ, cannot take the place of directly in circuit change.