august 1999 - revised january 2007 specifications are subject to change without notice. customers should verify actual device performance in their specific applications. tisp40xxh1bj vlv overvoltage protector series tisp4015h1bj, tisp4030h1bj, tisp4040h1bj very low voltage bidirectional thyristor overvoltage protectors description low capacitance ?015 ................................................................................... 78 pf ?030 ................................................................................... 62 pf ?040 ................................................................................... 59 pf digital line signal level protection -isdn -xdsl safety extra low voltage, selv, values device v drm v v (bo) v ?015 8 15 ?030 15 30 ?040 25 40 100 a ??series specified for: itu-t recommendations k.20, k.45, k.21 fcc part 68 and gr-1089-core wave shape standard i tsp a 2/10 s gr-1089-core 500 8/20 s iec 61000-4-5 400 10/160 s fcc part 68 200 10/700 s itu-t k.20/45/21 fcc part 68 150 10/560 s fcc part 68 125 10/1000 s gr-1089-core 100 these devices are designed to limit overvoltages on digital telecommunication lines. overvoltages are normally caused by a.c. p ower system or lightning flash disturbances which are induced or conducted on to the telephone line. a single device provides 2-point prote ction and is typically used for the protection of transformer windings and low voltage electronics. how to order the protector consists of a symmetrical voltage-triggered bidirectional thyristor. overvoltages are initially clipped by breakd own clamping until the voltage rises to the breakover level, which causes the device to crowbar into a low-voltage on-state condition. this low-vo ltage on state causes the current resulting from the overvoltage to be safely diverted through the device. the device switches off when the di verted current falls below the holding current value. device symbol smbj package (top view) 12 t(a) r(b) mdxxbge t r sd4xaa t erminals t and r correspond to the alternative line designators of a and b ............................................ ul recognized components *rohs directive 2002/95/ec jan 27 2003 including annex device package carrier tisp40xxh1bj smb (do-214aa) embossed tape reeled marking code 40xxh1 std. qty. 3000 tisp 40xxh1bjr-s insert xx value corresponding to protection voltages of 15 v, 30 v and 40 v. order as * r o h s c o m p l i a n t
august 1999 - revised january 2007 specifications are subject to change without notice. customers should verify actual device performance in their specific applications. absolute maximum ratings, t a = 25 c (unless otherwise noted) tisp40xxh1bj vlv overvoltage protector series electrical characteristics, t a = 25 c (unless otherwise noted) rating symbol value unit repetitive peak off-state voltage ?015 ?030 ?040 v drm 8 15 25 v non-repetitive peak on-state pulse current (see notes 1 and 2) i tsp a 2/10 s (telcordia gr-1089-core, 2/10 s voltage wave shape) 8/20 s (i ec 61000-4-5, combination wave generator, 1.2/50 voltage, 8/20 current) 10/160 s (fcc part 68, 10/160 s voltage wave shape) 5/310 s (i tu-t k.20/45/21, 10/700 s voltage wave shape) 5/320 s (f cc part 68, 9/720 s voltage wave shape) 10/560 s (fcc part 68, 10/560 s voltage wave shape) 10/1000 s (telcordia gr-1089-core, 10/1000 s voltage wave shape) 500 400 200 150 150 125 100 non-repetitive peak on-state current (see notes 1 and 2) i tsm a 20 ms (50 hz) full sine wave 16.7 ms (60 hz) full sine wave 0.2 s 50 hz/60 hz a.c. 2 s 50 hz/60 hz a.c. 1000 s 50 hz/60 hz a.c. 45 50 21 7 2 initial rate of rise of current (2/10 waveshape) di/dt 450 a/ s junction temperature t j -40 to +150 c storage temperature range t stg -65 to +150 c notes: 1. initially the device must be in thermal equilibrium with t j =25 c. 2. the surge may be repeated after the device returns to its initial conditions. parameter test conditions min typ max unit i drm repetitive peak off- state current v d =v drm 5 a v (bo) breakover voltage di/dt = 0.8 a/ms ?015 ?030 ?040 15 30 40 v v (bo) impulse breakover voltage dv/dt 1000 v/ s, linear voltage ramp, maximum ramp value = 500 v di/dt = 12 a/ s, linear current ramp, maximum ramp value = 10 a ?015 ?030 ?040 33 57 74 v i (bo) breakover current di/dt = 0.8 a/ms 0.8 a i d o v t i= 5 a, t = 100 s 3v tw on-state voltage ff-state current v d = 6v v d = 13 v v d = 22 v ?015 ?030 ?040 2 a i h holding current i t = 5a, di/dt=-/+30ma/ms 50 m a
august 1999 - revised january 2007 specifications are subject to change without notice. customers should verify actual device performance in their specific applications. tisp40xxh1bj vlv overvoltage protector series electrical characteristics, t a = 25 c (unless otherwise noted) (continued) c off off-state capacitance f=1mhz, v d =1v rms, v d =0 f=1mhz, v d =1v rms, v d =1v f=1mhz, v d =1v rms, v d =2v ?015 ?030 ?040 ?015 ?030 ?040 ?015 ?030 ?040 78 62 59 70 55 52 65 50 47 100 81 77 90 72 68 85 65 61 pf parameter test conditions min typ max unit thermal characteristics parameter test conditions min typ max unit r ja junction to free air thermal resistance eia/jesd51-3 pcb, i t = i tsm(1000) , t a = 25 c, (see note 3) 115 c/w 265 mm x 210 mm populated line card, 4-layer pcb, i t = i tsm(1000) , t a = 25 c 52 note 3: eia/jesd51-2 environment and pcb has standard footprint dimensions connected with 5 a rated printed wiring track widths.
august 1999 - revised january 2007 specifications are subject to change without notice. customers should verify actual device performance in their specific applications. tisp40xxh1bj vlv overvoltage protector series parameter measurement information figure 1. voltage-current characteristic for t and r terminals all measurements are referenced to the r terminal -v v drm i drm v d i h i tsm i tsp v (bo) i (bo) i d quadrant i i switching characteristic +v +i v (bo) i (bo) v drm i drm v d i d i h i tsm i tsp -i quadrant iii switching characteristic pm4ac
august 1999 - revised january 2007 specifications are subject to change without notice. customers should verify actual device performance in their specific applications. tisp40xxh1bj vlv overvoltage protector series typical characteristics figure 2. capacitance vs off-state voltage v d - off-state voltage - v 0.01 0.02 0.05 0.1 0.2 0.5 1 2 3 5 10 20 30 c off ? capacitance ? pf 20 30 40 50 60 70 80 tc4h1ae '4040 '4030 '4015 t j = 25 c v d = 1 vrms
august 1999 - revised january 2007 specifications are subject to change without notice. customers should verify actual device performance in their specific applications. tisp40xxh1bj vlv overvoltage protector series rating and thermal information figure 3. non-repetitive peak on-state current vs current duration t - current duration - s 0.01 0.1 1 10 100 1000 i tsm(t) - non-repetitive peak on-state current - a 1.5 2 3 4 5 6 7 8 15 20 30 40 50 60 10 ti4maj v gen = 600 vrms, 50/60 hz r gen = 1.4*v gen /i tsm(t) eia/jesd51-2 environment eia/jesd51-3 pcb t a = 25 c
august 1999 - revised january 2007 specifications are subject to change without notice. customers should verify actual device performance in their specific applications. figure 4. transformer saturation ai4xao th1 t1 unsaturated l rw th1 t1 saturated tisp40xxh1bj vlv overvoltage protector series applications information transformer protection the inductance of a transformer winding reduces considerably when the magnetic core material saturates. saturation occurs when the magnetizing current through the winding inductance exceeds a certain value. it should be noted that this is a different current to the transformed current component from primary to secondary. the standard inductance-current relationship is: where: l = unsaturated inductance value in h di = current change in a dt = time period in s for current change di e = winding voltage in v rearranging this equation and working large 6 changes to saturation gives the useful circuit relationship of: a transformer winding volt-second value for saturation gives the designer an idea of circuit operation under overvoltage condit ions. the volt-second value is not normally quoted, but most manufacturers should provide it on request. a 50 v s winding will support rectangular voltage pulses of 50 v for 1 s, 25 v for 2 s, 1 v for 50 s and so on. once the transformer saturates, primary to secondary coupling will be lost and the winding resistance, rw, shunts the overvoltage protector, th1 - see figure 4. this saturated condition is a concer n for long duration impulses and a.c. fault conditions because the current capability of the winding wire may be exceeded. for example, if the on-state voltage of the protector is 1 v and the winding resistance is 0.2 1 , the winding would bypass a current of 1/0.2 = 5 a, even through the protector was in the low voltage condition. el di dt ---- - = ex x 6 tl 6 i = ( ( figure 5 shows a generic protection arrangement. resistors r1 and r2, together with the overcurrent protection, prevent excessi ve winding current flow under a.c. conditions. normally these resistors would only be needed for special cases, e.g. some t1/e1 designs. a lternatively, a split winding could be used with a single resistor connecting the windings. this resistor could be by-passed by a small capacit or to reduce signal attenuation. figure 5. transformer winding protection th1 signal t1 over- current protect ion line r1 r2 ai4xan overcurrent protection upstream from the overvoltage protector can be fuse, ptc or thick film resistor based. for very high fre quency circuits, fuse inductance due to spiral wound elements may need to be evaluated. tisp device voltage selection normally, the working voltage value of the protector, v drm , would be chosen to be just greater than the peak signal amplitude over the equipment temperature range. this would give the lowest possible protection voltage, v (bo) . this would minimize the peak voltage applied to the transformer winding and increase the time to core saturation. in high frequency circuits, there are two further considerations. low voltage protectors have a higher capacitance than high vo ltage protectors.
august 1999 - revised january 2007 specifications are subject to change without notice. customers should verify actual device performance in their specific applications. tisp40xxh1bj vlv overvoltage protector series tisp device voltage selection (continued) so a higher voltage protector might be chosen specifically to reduce the protector capacitive effects on the signal. low energy short duration spikes will be clipped by the protector. this will extend the spike duration and the data loss time. a higher protector voltage will reduce the data loss time. generally, this will not be a significant factor for inter-conductor protection. however, clipping is significant for protection to ground, where there is continuous low-level a.c. common mode induction. in s ome cases the induced a.c. voltage can be over 10 v. repetitive clipping at the induced a.c. peaks by the protector would cause severe data c orruption. the expected a.c. voltage induced should be added to the maximum signal level for setting the protector v drm value. 2-wire digital systems typical systems using a single twisted pair connection are: integrated services digital network (isdn) and pair gain. signal level protection at the transformer winding is given by protectors th3 and th5. typically these could be tisp4015h1 type devices with a 15 v voltage protection level. figure 6. 2-wire system ai4xal signal transformer coupled two-wire interface dc supply th5 th4 c2 t2 over- current protection line th1 th2 th3 over- current protection dc feed signal c1 t1 two line protection circuits are given; one referenced to ground using th1 and th2 (left) and the other inter-wire using protec tor th4 (right) - see figure 6. for isdn circuits compliant to etsi etr 080:1993, ranges 1 and 2 can be protected by the following device types: tisp4095m3, tisp4095h3, tisp3095h3 (combines th1 and th2) and tisp7095h3 (combines th1, th2 and th4). ranges 4 through 5 can be protected b y: tisp4145m3, tisp4145h3, tisp3145h3 (combines th1 and th2) and tisp7145h3 (combines th1, th2 and th4). device surge requirement, h or m, will be set by the overcurrent protection components and the standards complied with. protection of just the d.c. feed to etsi ranges is covered in the tisp5xxxh3 data sheet. when loop test voltages exceed the normal d.c. feed levels, higher voltage protectors need to be selected. for two terminal pro tectors, for levels up to 190 v (135 v rms) the tisp4250, h3 or m3, can be used and for 210 v (150 v rms) the tisp4290, h3 or m3, can be use d. in pair gain systems, the protector v drm is normally set by the d.c. feed value. the following series of devices have a 160 v working voltage at 25 c: tisp4220m3, tisp4220h3, tisp3210h3 (combines th1 and th2) and tisp7210h3 (combines th1, th2 and th4). these devices can be used on 150 v d.c. feed voltages down to an ambient temperature of -25 c. where the subscriber equipment may be exposed to pots (plain old telephone service) voltage levels, protector th4 needs a higher working voltage of about 275 v. suitable device type s are: tisp4350m3, tisp4350h3, tisp3350h3 (combines th1 and th2) and tisp7350h3 (combines th1, th2 and th4). the overcurrent protection for the overvoltage protector can be fuse, ptc or thick film resistor based. its a.c. limiting capab ility should be less than the ratings of the intended overvoltage protector. equipment complying with the year 2000 international k.20, k.21 and k.4 5 recommendations from the itu-t, may be required to demonstrate protection coordination with the intended primary protector. wit hout adding series resistance, a simple series fuse overcurrent protection is likely to fail the equipment for this part of the recommendat ion. if the d.c. feed consists of equal magnitude positive and negative voltage supplies, appropriately connected tisp5xxxh3 unidire ctional protectors could replace th1 and th2. 4-wire digital systems a typical system using a two twisted pair connection is the high-bit-rate digital subscriber line (hdsl) and the s interface of isdn. figure 7 shows a generic two line system. hdsl tends to have ground referenced protection at both ends of the lines (th1, th2, th3 and th4). the isdn s interface is often inside the premises and simple inter-wire protection is used at the terminating adaptor (th7 an d th8). in all
august 1999 - revised january 2007 specifications are subject to change without notice. customers should verify actual device performance in their specific applications. tisp40xxh1bj vlv overvoltage protector series 4-wire digital systems figure 7. 4-wire system ai4xam dc feed th9 signal th10 signal transformer coupled four-wire interface th7 th8 t3 t4 over- current protection over- current protection line 1 line 2 over- current protection over- current protection th5 th6 th1 th2 th3 th4 dc supply signal signal t1 t2 cases, signal protection, th5, th6, th9 and th10, can be tisp4015h1 type devices with a 15 v voltage protection level. for an hdsl d.c. feed voltage of 180 v or less and operation down to an ambient of -25 c, the following th1, th2, th3 and th4 protectors are suitable: tisp4250m3 or tisp4250h3, tisp3250h3 (combines th1 and th2 or th3 and th4) and tisp7250h3 (combines th1, th2 and th7 or th3, th4 and th8). possible overcurrent protection components are covered in the 2-wire digital systems clause. for isdn interfaces powered with 40 v (etsi, ets 300 012 1992) the following th1, th2, th3 and th4 protectors are suitable: tisp4070m3 or tisp4070h3 or tisp4070l3, tisp3070f3 or tisp3070h3 (combines th1 and th2 or th3 and th4) and tisp7070f3 or tisp7070h3 (combines th1, th2 and th7 or th3, th4 and th8). at the terminating adaptor, the th7 and th8 protectors do not see the d.c. feed voltag e and should be selected to not clip the maximum signal level. generally, the tisp40xxh1 series will be suitable. internal isdn lines are not exposed to high stress levels and the chances of a.c. power intrusion are low (etsi en 300 386-2 19 97). accordingly, the equipment port protection needs are at a lower level than ports connected to outside lines. home phone networking using the existing house telephone wiring, home phone networking systems place the local network traffic in a high band above t he pots and adsl (asymmetrical digital subscriber line) spectrum. local network rates are 1 mbps or more. to reject noise and harmonics, an in-line protection and 5 mhz to 10 mhz bandpass filter module is used for the equipment. these modules are available from magnetic comp onent manufacturers (e.g. bel fuse inc.) a typical circuit for the telephone line magnetics module is shown in figure 8. transformer t1 isolates the equipment from the house wiring. the isolated winding output is voltage limited by a very low-voltage protector, th1. with a di fferential voltage of about 12 v peak to peak, the tisp4015h1 could be used for th1. after filtering, connection is made to the differential trans ceiver of the processing ic. figure 8. home phone networking isolation/filter/protection circuit ai4xap th1 filter c1 t1 tip ring protection hrtrx+ hrtrx- tisp is a trademark of bourns, ltd., a bourns company, and is registered in u.s. patent and trademark office. bourns is a registered trademark of bourns, inc. in the u.s. and other countries.
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