SEMIPACK® Thyristor/Diode Modules Features•Modules with isolated baseplate and thyristor and/or diode chips for currents up to 1200A and reverse voltages up to 2200 V•Available as single component elements or as double packs with internal, functional interconnection •Case with copper baseplate in 7 sizesSEMIPACK® 0: 61 x 21 mm, module height 23.2 mm SEMIPACK® 1: 93 x 20 mm, module height 30 mmSEMIPACK® 2: 94 x 29 mm, module height 30 mmSEMIPACK® 3: 115 x 51 mm, module height 52 mm SEMIPACK® 4: 101 x 50 mm, module height 52 mm SEMIPACK® 5: 150 x 60 mm, module height 52 mm SEMIPACK® 6: 104 x 70 mm, module height 90 mm SEMITRANS® 4: 107 x 62 mm, module height 37 mm (fast, high-current modules SKKE 330F, SKKE 600F with CAL diodes)•Screw connections for power interconnect (SEMI-PACK® 0: Fast-on tabs)•Semiconductor chips soldered onto ceramic isolated metal baseplate (SEMIPACK® 0...2 and some SEMI-PACK® 3, SEMITRANS® 4 modules) or pressure con-tact modules (SEMIPACK® 3, 4, 5, 6) with very high load cycle capability•Optimum heat transfer to heat sink thanks to ceramic isolated metal baseplate with Al2O3 (SEMIPACK® 0, 1,2) or AlN (SEMIPACK® 3, 4, 5, 6) insulating substrateand copper baseplate•No hard mould (Exceptions: SEMIPACK® 0 and some SEMIPACK® 1 modules•Thyristor chips in SEMIPACK® 3...6 with amplifying gate to reduce the gate current•Fast diode modules with diodes in diffusion, Epitaxial and CAL (Controlled Axial Lifetime) technology up to 600 A and 1700 V•Insulation voltage up to 4 kVrms for 1 min., 4.8kV rms for 1 s•UL approval in accordance with UL1557, Reference no. E63532Technical ExplanationsThe terms in [ ] apply to thyristors onlyInsulation voltage V isolThe insulation voltage of SEMIPACK® modules is a gua-ranteed value for the insulation between the terminals and the baseplate. The limiting value 3.6kV rms specified for 1s is subject to 100 % production testing.All terminals - including the gate connections - must be interconnected during dielectric testing. All specifications for the final product's dielectric test voltage are described in the IEC publications IEC60146-1-1:1991 and EN60146-1-1:1994 Section 4.2.1 (=VDE0558 T1-1: 1993), EN 50178:11.1997 (= DIN EN50178 (VDE 0160): 1998, as well as in UL1557: 1997. For railway applications, for instance, please refer to the specificati-ons of the IEC61287-1 standard.Non-repetitive peak reverse voltage V RSM; [Non-repeti-tive peak off-state voltage V DSM]Maximum permissible value for non-repetitive, occasio-nally transient peak voltages.Repetitive peak reverse voltage V RRM [and off-state voltage V DRM]Maximum permissible value for repetitive transient off-state and reverse voltages.Direct blocking voltages V R, [V D] for continuous duty Maximum permissible direct reverse voltage for stationary operation for diodes (V R) [or thyristors (V D, V R)]. This value is 0.7 V RRM [0.7 V DRM].Mean forward [on-state] current I FAV, [I TAV]The symbols I FAV, [I TAV] are used to refer to both the mean current values in general and the current limits. The limi-ting values are absolute maximum continuous values for the on-state current load of a diode [thyristor] for a given current waveform and given cooling conditions (e.g. case temperature T c). At this current value, the maximum per-missible junction temperature is reached, with no margins for overload or worst-case reserves. The recommended maximum continuous current is therefore approximately 0.8 I TAV . For operation frequencies of between 40 Hz and 200 Hz the maximum mean on-state current can be taken from Fig. 1 of the datasheet. If standard diodes and thyri-stors (diodes/thyristors for line application) are operated at frequencies of between 200 Hz and 500 Hz, further cur-rent reductions should be carried out to compensate for the switching losses that are no longer negligible.RMS forward [on-state] current I FRMS, [I TRMS]The symbols I FRMS, [I TRMS] are used to refer to both the mean current values and the current limits. The limiting values are absolute maximum values for the continuous on-state current for any chosen current waveform and cooling conditions.Surge forward [on-state] current I FSM [I TSM]Crest value for a surge current in the form of a single sinu-soidal half wave which lasts for 10 ms. After occasional current surges with current values up to the given surge forward current, the diode [thyristor] can withstand the119120© by SEMIKRONreverse voltages specified in Fig. 8 or Fig. 16 of the data sheets.Surge current characteristics I F(OV), [I T(OV)]Crest values for full or part sinusoidal half wave currents lasting between 1 ms and 10 ms or for sequential sinusoi-dal half wave currents with a maximum duration of 10 ms,permissible under fault conditions only, i.e. the diode [thy-ristor] may only be subjected to this value occasionally;the controllability of a thyristor may be lost during over-load. The overload current depends on the off-state voltage value across the component (cf. Fig. 8 or Fig. 16of the data sheets).i 2t valueThis value is given to assist in the selection of suitable fuses to provide protection against damage caused by short circuits and is given for junction temperatures of 25°C and 125 °C. The i 2t value of the fuse for the intended input voltage and the prospective short circuit in the device must be lower than the i 2t of the diode [thyristor] for t =10ms. When the operating temperature increases, the i 2t value of the fuse falls more rapidly than the i 2 t value of the diode [thyristor], a comparison between the i 2t of the diode (thyristor) for 25 °C and the i 2t value of the (unloaded) fuse is generally sufficient.[Critical rate of rise of on-state current (di/dt)cr ]Immediately after the thyristor has been triggered, only part of the chips conducts the current flow, meaning that the rate rise of the on-state current has to be limited. The critical values specified apply to the following conditions:repetitive loads of between 50 and 60 Hz; a peak current value corresponding to the crest value of the permissible on-state current for sinusoidal half waves; a gate trigger current that is five times the peak trigger current with a rate of rise of at least 1 A/μs. The critical rate of rise for on-state current falls as the frequency increases, but rises as the peak on-state current decreases. For this reason, for fre-quencies >60 Hz and pulses with a high rate of rise of cur-rent, the peak on-state current must be reduced to values below those given in the datasheets.[Critical rate of rise of off-state voltage (dv/dt)cr ]The values specified apply to an exponential increase in off-state voltage to 0.66 V DRM . If these values are excee-ded, the thyristor can break over and self trigger.Direct reverse [off-state] current I RD [I DD ]Maximum reverse or off-state [for thyristors] current for the given temperature and maximum voltage. This value depends exponentially on the temperature.Direct forward [on-state] voltage V F [V T ]Maximum forward voltage across the main terminals for a given current at 25°C.Threshold voltage V (TO) [V T(TO)] and Forward [on-state] slope resistance r TThese two values define the forward characteristics (upper value limit) and are used to calculate the instanta-neous value of the forward power dissipation P F [P T ] or the mean forward power dissipation P FAV [P TAV ]:P F[T] = V T(TO) * I F[T] + r T * i 2F[T]P F[T]AV = V T(TO) * I F[T]AV + r T * I 2F[T]RMS I 2F[T]RMS / I 2F[T]AV = 360° / Θfor square-wave pulses I 2F[T]RMS / I 2F[T]AV = 2.5 orI 2F[T]RMS / I 2F[T]AV = (π/2)2 * 180° / Θfor [part] sinusoidal half waves Θ: Current flow anglei F[T]: Instantaneous forward current value I F[T]RMS : RMS forward [on-state] current I F[T]AV : Mean forward [on-state] current [Latching current I L ]Minimum anode current which at the end of a triggering pulse lasting 10 μs will hold the thyristor in its on-state. The values specified apply to the triggering conditions stipula-ted in the section on "Critical rate of rise of on-state cur-rent".[Holding current I H ]Minimum anode current which will hold the thyristor in its on-state at a temperature of 25 °C. If the thyristor is swit-ched on at temperatures below 25 °C, the values specified may be exceeded.Recovery charge Q rrQ rr is the total charge which flows through the main circuit (current-time area) during commutation against the reverse recovery time t rr . The corresponding characteristic in the datasheet shows this value's dependence on the forward current threshold value I FM [I TM ] before commuta-tion, as well as the forward current rate of fall di/dt (cf.Fig.1).Fig. 1 Current curve during diode/thyristor turn-off© by SEMIKRONModules – Explanations – SEMIPACK121The following relations exist between t rr , Q rr , the current fall time t f and the peak reverse recovery current I RM (cf.Fig. 1):t rr = I RM / (- di F[T]/dt) + t fI RM = 2 * Q rr / t rrIf the fall rate of the forward current I F [I T] is very low, t f will be small in comparison to t rrand the equations can be sim-plified as follows:Further details, in particular with regard to fast diode swit-ching, can be found in the section "Fast rectifier diodes"under "Diode turn-off".[Circuit commutated turn-off time t q ]The circuit commutated turn-off time lies in the range of several hundred μs and constitutes the time required for a thyristor to discharge to allow it to take on forward voltage again. This value is defined as the time that elapses bet-ween zero crossing of the commutation voltage and the earliest possible load with off-state voltage. In the case of thyristors for phase-commutated converters and a.c. con-verters, the circuit commutated turn-off time is usually of no significance. For this reason, the datasheets contain typical values only, and no guarantee is given for these values.[Gate trigger voltage V GT and Gate trigger current I GT ]Minimum values for square-wave triggering pulses lasting longer than 100 μs or for d.c. with 6 V applied to the main terminals. These values will increase if the triggering pul-ses last for less than 100 μs. For 10 μs, for instance, the gate trigger current I GT would increase at least by a factor of between 1.4 and 2. It´s recommended that firing circuits should therefore be arranged in such as way that trigger current values are 4 to 5 times larger than I GT . If the thyri-stor is loaded with reverse blocking voltage, no trigger voltage may be applied to the gate in order to avoid a non-permissible increase in off-state power losses and the for-mation of hot spots on the thyristor chip.[Gate non-trigger voltage V GD und Non-trigger current I GD ]These trigger voltage and current values will not cause the thyristor to fire within the permissible operating tempera-ture range. Inductive or capacitive interference in the trig-gering circuits must be kept below these values.[Time definitions for triggering]Fig. 2 shows the characteristics of gate trigger signal V Gand anode-cathode voltage V AK which define the time intervals for the triggering process.Fig. 2 Time definitions for thyristor triggering[Gate-controlled delay time t gd ]: Time interval between the start of a triggering pulse and the point at which the anode-cathode voltage falls to 90 % of its starting value.The datasheet specifies a typical value which is applica-ble, provided the following conditions are fulfilled:- Square-wave gate pulse, duration 100 μs - Anode-cathode starting voltage 0.5 V DRM- On-state current after firing approx. 0.1 I TAV @ 85 °C - Junction temperature during firing approx. 25 °C [Gate controlled rise time t gr ]: Period within which the anode-cathode voltage falls from 90 % to 10 % of its star-ting value during firing.[Gate current pulse duration t gt ]: The sum of the gate controlled delay time t gd and the gate controlled rise time t gr .Thermal resistances R th(x-y) and thermal impedances Z th(x-y)For SEMIPACK ® modules, thermal resistances/impedan-ces are given for the heat flow between points "x" and "y".The indices uses are as follows:j - junction c - case/baseplate s - sinkr - reference point a - ambientThe contact thermal resistance case to heatsink R th(c-s)applies provided the assembly instructions are followed. In such cases, the given dependences of the internal thermal resistance junction to case R th(j-c) on the current waveformand the current flow angle should take into account any deviations from the maximum instantaneous value of the mean junction temperature calculated. The values given in the datasheet tables apply to sinusoidal half waves only. Values for other current wave forms can be taken from Fig.7 of the datasheet.The thermal resistance junction to ambient R th(j-a) to be used in Fig. 1 and Fig.11 of the datasheet comprises the following components:R th(j-a) = R th(j-c) + R th(c-s) + N * R th(s-a)where N: the number of thyristors or diodes operating simultaneously on one heat sink.The thermal resistance R th(s-a) of the heat sink decreases as the following items increase: power dissipation, the cooling air flow rate, the number of SEMIPACK® modules mounted and the distance between the individual modu-les.The transient thermal impedances in the SEMIPACK®modules Z th(j-c) and Z th(j-s) are shown in the diagrams shown in Fig. 6 and Fig 14 of the datasheets as a function of the time t. For times > 1 s, the transient thermal impe-dance Z th(s-a) of the heat sink must be added to this in order to calculate the total thermal impedance. For this purpose, the datasheets for SEMIKRON heat sinks normally con-tain a diagram illustrating the given thermal impedance Z th(s-a) or Z th(c-a) as a function of the time t. When several components are being mounted on one heat sink, in order to calculate the transient thermal impedance of one com-ponent, the thermal heat sink impedance must be multip-lied by the total number of components N. TemperaturesThe most important referential value for calculating limiting values is the maximum permissible virtual junction tempe-rature T vj. At most in the event of a circuit fault (e.g. when a fuse is activated) may this value be exceeded briefly (cf. "Surge on-state current"). Another important reference point for the permissible current capability is the case tem-perature T c. In SEMIPACK® modules, the measuring point for T c (Reference point/Reference temperature T cref) is the hottest point of the baseplate beneath the hottest chip, measured through a hole in the heat sink. The heat sink temperature T s is of particular interest for defining power dissipation and heat sink. In SEMIPACK® modules the measuring point for T s (Reference point/Reference tempe-rature T sref) is the hottest point of the heat sink besides the baseplate, measured from above on the side wall of the module (cf. also IEC60747-1, Am. 1 to Am. 3 and IEC60747-15 cls.7.4.3).The permissible ambient conditions without current or voltage stress are described, among other things, by the maximum permissible storage temperature T stg. The para-meter T stg is also the maximum permissible case tempera-ture which must not be exceeded as a result of internal or external temperature rise.Mechanical limiting valuesThe limiting values for mechanical load are specified in the datasheets, e.g.:Mn : Max. tightening torque for terminal screws and faste-nersFt : Max. permissible mounting force (pressure force) forcapsule devicesa : Max. permissible amplitude of vibration or shock acce-leration in x, y and z direction.If SEMIPACK® modules with no hard mould are to be usedin rotating applications, the soft mould mass may comeaway and leak. Please contact SEMIKRON for there appli-cations.Application NotesThe terms in [ ] apply solely to thyristors.Voltage class selectionThe table below contains the recommended voltage class allocations for the repetitive peak reverse voltages V RRM,[V DRM ] of SEMIPACK® modules and (sample) rated ACinput voltage V VN (samples).As detailed in the technical explanations, the maximum permissible value for direct reverse voltages (continuousduty) across diodes (V R) [or thyristors (V D, V R)] in statio-nary operation is 0.7 V RRM [0.7 V DRM].Overvoltage protectionRC snubber circuits are often connected in parallel to thediode [thyristor] to provide protection from transient over-voltage, although in some cases varistors are used. Dueto the RC circuit the rate of rise of voltage is limited during commutation, which reduces the peak voltages across thecircuit inductors.For higher circuit requirements, the RC circuit designshould first be tested experimentally. The table below con-Rated AC voltage L-L Recommended peakreverse voltageV VN / V V RRM, [V DRM] / V60200125 400250 8003801200400 140044014004601600500 160057518006602200690 2200122123tains sample resistance and capacitance values recom-mended by SEMIKRON for standard line applications SEMIPACK ® ModulesOver-current and short circuit protectionIf short circuit protection is required for the diodes, [thyri-stors], (ultra fast) semiconductor fuses are used. These are to be dimensioned on the basis of the forward current and i 2t value.Other types of protection for high current circuits are, for example, fuses which isolate damaged diodes [thyristors]from the parallel connections. To protect components from statically non-permissible high overcurrents, it is possible to use magnetic or thermal overcurrent circuit breakers or temperature sensors on the heat sinks, although these do not detect dynamic overload within a circuit. For this rea-son, temperature sensors are used mainly with forced air cooling in order to prevent damage to the diodes [thyri-stors] in the event of fan failure.Permissible overcurrentsThe permissible forward currents for short-time or interme-diate operation, as well as for frequencies below 40 Hz are to be calculated on the basis of the transient thermal impe-dance or the thermal impedance under pulse conditions so that the virtual junction temperature T vj does not exceed the maximum permissible value at any time.Assembly instructionsIn order to ensure good thermal contact and to obtain the thermal contact resistance values specified in the datas-heets, the contact surface of the heat sink must be clean and free from dust particles, as well as fulfilling the follo-wing mechanical specifications:•Unevenness: < 20 μm over a distance of 100 mm •Roughness R Z : < 10 μmBefore assembly onto the heat sink, the module baseplate or the contact surface of the heat sink is to be evenly coated with a thin layer (approx. 50 μm) of a thermal com-V VN ≤ 250V V VN ≤ 400V V VN ≤ 500V V VN ≤ 660VSKK_15 (27)0.22μF 68Ω/ 6W 0.22μF 68Ω/ 6W0.1μF 100Ω/10W- -SKK_42...1060.22μF 33Ω/ 10W 0.22μF 47Ω/ 10W 0.1μF 68Ω/ 10W 0.1μF 100Ω/10WSKK_122...260 (on P3 heatsink)0.22μF33Ω/ 10W 0.22μF 47Ω/ 10W 0.1μF 68Ω/ 10W 0.1μF 100Ω/10W SKK_122 (260)(higher currents)0.47μF33Ω/ 25W 0.47μF 33Ω/ 25W 0.22μF 47Ω/ 25W 0.22μF 68Ω/ 50W pound such as Wacker-Chemie P 12 (silicon-based, 30 g tube: SEMIKRON ID No. 30106620). For even distribution we recommend using a hard rubber roller or a silk screen process. The SEMIPACK ® modules should be secured with the following DIN steel screws: M4 (SEMIPACK ® 0),M5 (SEMIPACK ® 1, 2, 4) or M6 (SEMIPACK ® 3, 5) (pro-perty class 8.8) in combination with suitable washers and spring lock washers or combination screws. When doing so, the torque value specified in the datasheet must be observed. The screws must be tightened in diagonal order with equal torque in several steps until the specified torque value M1 has been reached. We further recommend that the screws are retightened according to the given torque,value following a period of a few hours, as part of the heat sink compound may spread under the mounting pressure.For the electrical terminals, suitable screws, washers and spring lock washers or combination screws are to be used.We also recommend using contact rails for the power ter-minals in SEMIPACK ® modules. If connecting leads are used, suitable steps must be taken to prevent non-permis-sible tensile and shear stress on the power connections.Furthermore, the maximum and minimum thread reaches,which can be taken from the module drawings (see data sheets), and the permissible tightening torque values M2must be observed. When soldering flat plug connectors (using a grounded solder tool), a soldering temperature of T solder = 245 ± 5°C / <20sec. must be observed.All gate control cables must be kept as short as possible in order to minimise stray inductance and prevent electro-magnetic interference and oscillation from occurring. In the case of SEMIPACK ® thyristor modules with auxiliary cathode terminals, the gate and cathode control leads are to be twisted together, as far as possible.The tables below contain details on the contents of the mounting accessory kits for the respective SEMIPACK ®module (SEMIPACK ® 1...4).ContentsSEMIPACK ® 1for 12 modules SEMIKRON ID No.33403900Mounting screws 24 pcs M5x18 Z4-1 DIN 7984-8.8Connection screws 36 pcs M5x10 Z4-1 DIN 7985-4.8Plain washersPart of combi-screw Spring lock washers Part of combi-screwPush-on receptacles 48 pcs B2.8-1 for connec-tors 2.8x0.8mm Insulating sleeves48 pcs 6x3.5x20Contents SEMIPACK ® 2for 8 modulesSEMIKRON ID No.33404000Mounting screws 16 pcs M5x18 Z4-1 DIN7984-8.8Connection screws24 pcs M6x12 Z4-1 DIN7985-8.8Push-on receptacles32 pcs A2.8-0.25 for con-nectors 2.8x0.8mm Insulating caps Left and right, 8 pcs each15x9.8x6.8Contents SEMIPACK® 3for 3 modules SEMIKRON ID No.33404100Mounting screws12 pcs M5x18 Z4-1 DIN7984-8.8Connection screws9 pcs M8x16 Z4-1 DIN 933-8.8Plain washers Part of combi-screw Spring lock washers Part of combi-screwPush-on receptacles12 pcs A2.8-0.25 for con-nectors 2.8x0.8mm Insulating caps Left and right, 3 pcs each15x9.8x6.8Contents SEMIPACK® 4for 3 modules SEMIKRON ID No.33404500Mounting screws12 pcs M5x18 Z4-1 DIN7984-8.8Connection screws Threaded pin, 6 pcsM10x50 DIN 916-45 H Spring lock washers 6 x conical spring washersA10 DIN 6796Hex nut 6 pcs M10 DIN 934Push-on receptacles 6 pcs A2.8-0.25 for connec-tors 2.8x0.8 mm Insulating caps 3 pcs right SEMIPACK®: Thyristor/Diode Modules with Thyristor and Diodes for Line ApplicationType Designation Systemn o p q r s tSK K T430/22E H4n SEMIKRON componento Internal connectionE: Single elementK: followed by D, H, L or T = Series connection with centre tap (phase leg)followed by Q = Anti parallel connection (AC controller) followed by E = Single diodeM: Centre-tapped connection, common cathodeN: Centre-tapped connection, common anodep Functional elements and configurationD: All elements diodesE: Single diodeH: Thyristor (cathode-side) + diodeL: Thyristor (anode-side) + diodeQ: Anti-parallel thyristorsT: All elements thyristorsq Rated current (I TAV [A])r Voltage class (V RRM [V]/100)s dv/dt classD: 500 V/μsE: 1000 V/μst Option, where applicable, e.g. H4 = V isol 4,8 kV/1s Captions of the FiguresSEMIPACK® thyristor modulesFig. 1Left: Power dissipation P TAV as a function of the mean on-state current I TAV for d.c. (cont.), sinusoidal half waves (sin. 180) and square-wave pulses (rec. 15...180) for a sin-gle thyristor (typical values)Right: Max. permissible power dissipation P TAV as a function of the ambient temperature T a (temperature of the cooling air flow) for the total thermal resistances (junction to ambient air) R th(j-a) (typical values)Fig. 2Left: Total power dissipation P TOT of a SEMIPACK®module used in an a.c. controller application (W1C a.c.124converter) as a function of the maximum rated rms current I RMS at full conduction angle (typical values)Right: Max. permissible power dissipation P TOT and resul-tant case temperature T c as a function of the ambient tem-perature T a; Parameter: Heatsink thermal resistance case to ambient air R th(c-a) (including the total contact thermal resistance 1/2 R th(c-s) between a SEMIPACK® module and the heat sink. For the power dissipation given on the l.h.s vertical, the case temperatures given on the r.h.s. vertical are permissibleFig. 3Left: Total power dissipation P TOT of 2 SEMIPACK®modules in a two-pulse bridge connection (B2C) as a function of the output direct current I D at full conduction angle for resistive (R) and inductive (L) load (typical values)Right: Max. permissible power dissipation P TOT and resul-tant case temperature T c as a function of the ambient tem-perature T a; Parameter: Heatsink thermal resistance case to ambient air R th(c-a) (including the total contact thermal resistance 1/4 R th(c-s) between a SEMIPACK® module and the heat sink. For the power dissipation given on the l.h.s vertical, the case temperatures given on the r.h.s. vertical are permissibleFig. 4Left: Total power dissipation P TOT of 3 SEMIPACK®modules in a six-pulse bridge connection (B6C) or in an a.c. controller connection (W3C) as a function of the direct output current I D at full conduction angle resistive (R) and inductive (L) load (typical values)Right: Max. permissible power dissipation P TOT and resul-tant case temperature T c as a function of the ambient tem-perature T a; Parameter: Heatsink thermal resistance case to ambient air R th(c-a) (including the total contact thermal resistance 1/6 R th(c-s) of a SEMIPACK® module and the heat sink. For the power dissipation given on the l.h.s ver-tical, the case temperatures given on the r.h.s. vertical are permissibleFig. 5 Typical recovery charge Q rr for the max. permissible junction temperature as a function of the rate of fall of the forward current -di T/dt during turn-off, Parameter: Peak on-state current I TM before commutationFig. 6 Transient thermal impedances junction to case Z th(j-c) and junction to sink Z th(j-s) for d.c. as a function of thetime t elapsed after a step change in power dissipation, for a single thyristorFig. 7 Forward characteristics: on-state voltage V T as a function of the on-state current I T; typical and maximum values for T vj = 25 °C and T vjmaxFig. 8 Surge current characteristics: Ratio of permissible overload on-state current I T(OV) for 10 ms to surge on-state current I TSM, shown as a function of the load period t; Para-meter: Ratio V R / V RRM of the reverse voltage V R between the sinusoidal half waves, to the peak reverse voltage V RRM Fig. 9 Gate voltage V G as a function of the gate current I G, indicating the regions of possible (BMZ) and certain (BSZ) triggering for various virtual junction temperatures T vj. The current and voltage values of the triggering pulses must lie within the range of certain (BSZ) triggering, but the peak pulse power P G must not exceed that given for the pulse duration t p. Curve 20 V; 20 Ω is the output characteristic of suitable trigger equipment.SEMIPACK® diode modulesFig. 11Left: Mean power dissipation P FAV as a function of the mean continuous forward current I FAV for d.c. (cont.), sinu-soidal half waves (sin. 180) and square-wave pulses (rec.15...180) for a single diode (typical values)Right: Max. permissible power dissipation P FAV as a function of the ambient temperature T a (temperature of the cooling air flow) for different total thermal resistances (junction to ambient air) R thja (typical values)Fig. 12Left: Total power dissipation P TOT of 2 SEMIPACK®modules in a two-pulse bridge connection (B2C) as a function of the output direct current I D (typical values) Right: Max. permissible power dissipation P TOT and resul-tant case temperature T c as a function of the ambient tem-perature T a; Parameter: Heatsink thermal resistance case to ambient air R th(c-a) (including the total contact thermal resistance 1/4 R th(c-s) between a SEMIPACK® module and the heat sink. For the power dissipation given on the l.h.s vertical, the case temperatures given on the r.h.s. vertical are permissibleFig. 13Left: Total power dissipation P TOT of 3 SEMIPACK®modules in a six-pulse bridge connection (B6C) as a function of the direct output current I D (typical values) Right: Max. permissible power dissipation P TOT and resul-tant case temperature T c as a function of the ambient tem-perature T a; Parameter: Heatsink thermal resistance case to ambient air R th(c-a) (including the total contact thermal resistance 1/6 R th(c-s) between a SEMIPACK® module and the heat sink. For the power dissipation given on the l.h.s vertical, the case temperatures given on the r.h.s. vertical are permissibleFig. 14 Transient thermal impedances junction to case Z th(j-c) and junction to heat sink Z th(j-s) of a single diode for d.c. as a function of the time t elapsed after a step change in power dissipationFig. 15 Forward characteristics: forward voltage V F as a function of the forward current I F; typical and maximum values for T vj = 25 °C and T vjmaxFig. 16 Surge current characteristics: Ratio of permissible overload on-state current I T(OV) to surge on-state current I TSM for 10 ms as a function of the load period t; Parameter: Ratio V R / V RRM of the reverse voltage V R between the sinusoidal half waves, to the peak reverse voltage V RRM125。