Technical Data Printed order nr. D GHS 30392 E BBC _ Silicon-Semiconductor BROWN BOVERI Com ponents Rectifier-Diodes A A P n K A = Anode K = Cathode a) K b) ip Year v Forward or Rsht conduction region * uae Vv, TO, Reverse or 7) blocking region BBC 866336 c) ig Forward current VE = Forward voltage drop V(TO)} Threshold voltage V(BR) = Break down voltage Vrsm = Non repetitive peak reverse voltage Figure 1: Diode a) Symbol, switch sign b) schematical constitution C) Vp - ip characteristic di _ 0,25 Ip, Iep ; ee Orr le = Twar eee ety a rr = Rev overy BBC 73.6056 current, peak value try = Reverse recovery time Qr, = Reverse recovered charge = Rate of rise of forward current Figure 2: Current wave form during commutation of the diode fram conduction state to the blocking state. (DIN 41781 page 10) Diodes are electric devices which conduct current in one direction i.e. offer a low resistance, while blocking i.e. offering a high resistance, in the reverse direction. Silicon, proving especially efficient in the higher power range, is preferrably employed for the production of semiconductor diodes. Fig. 1c shows the characteristic of a semiconductor diode in forward and reverse direction. In the standard range (type code DS..) the reverse voltage must not exceed even temporarily the non repetitive reverse voltage Vrgm. Avalanche diodes of the DSA range may temporarily be exposed to voltages of the order of the break down voltage V(r). Standard-type diodes are as a rule employed in circuits with line voltage supply (50-60 Hz). For use at higher frequencies (nearly off 1000 Hz) the dynamical properties during turn-on and turn-off should be taken into consideration. Fast recovery diodes of the DSD range have good dynamical properties. The criterion of the quickness of a diode is the reverse recovery time t,, indicated as time interval between the turn-off of the forward current and the instant a certain value of the reverse voltage is reached (see Fig. 2). On changing over from the conducting to the non-conducting state the charge carrier quantity stored in the junction give rise to an excessive inverse current, the so-called recovery reverse current Irr, immediately after passage of the current through zero. After the reverse recovery time has elapsed the reverse current is interrupted and finally decays to the steady state value of the inverse current. This phenomenon is known as hole storage effect and the integration of the current-time-area in reverse direction eventually gives the reverse recovered charge Qrr. Fast diodes featuring lower Q;; and trr values than standard-type diodes, their reverse power losses is lower, which again results in a higher efficiency. Type code of Brown Boveri diodes Example: DS A135-14A ps ____-__ Silicon diode (standard) A_. Avalanche type D_______. Fast recovery type | _____ Inverse polarity (cathode stud mounted) 35 -._ Current rating in ampere -14_ Voltage class (14 + 1400 V) A Modification Glossary of terms and symbols Terms and symbols largely correspond to the international recommendations ( *) VrRM 7 Repetitive peak reverse voltage, instantaneous value VE == Forward voltage drop, maximum value at rated IF = i issi . Prsm = Maximum reverse power surge for avalanche diodes at leRMS Maximum permissible forward current, RMS value RS O(va)max and 10 ws pulse width leEayvm = Mean forward current, 40 to 000 Hz of one halfsine wave Oy) = Virtual junction temperature at Yamb = 45C, convection cooling and Rinya: resP- 8(vJ)max = Maximum junction temperature Pcase 100C and Rinse Pamb = Ambient temperature lesm@ = Peak one cycle surge forward current, 10 ms, starting %case = Case temperature temperature #, Rihuc = Thermal resistance junction to case (VJ}max t ; . 9 = fust RthJA == Thermal resistance junction to ambient fi dt = Mt for fusing tery = Reverse recovery time at 26 C IR = Maximum reverse current at 9yvjymax and VRRM Qrr == Reverse recovered charge at 25 CStandard and Avalanche Diodes leave: ...1 up to il A BBC 726401 ERR Mataraceeancontnenntre Type VRRM | 'FRMS | 'FAVM | 'rsm_ | fizdt IR VF Prsm |? Rthuc |Rthya | Weight | Outline (ref. ip) |@ (Vmax Standard Avalanche v A A A As mA Vv kw c 2CAW {C/W |g Nr. 4.N 4002 100 1,6 1 27 3,7 03 {S14 175 _ 60 0,4 1 4003 ~ 200 (amb (1A) 4004 400 <750C) 4005 _ 600 4006 800 4007 1000 DS 0,9-04 A 400 5 2 50 42 <1 3 4 fe. 75 5 2 +} | ger 0 305 } _ Le fs)