protection products 1 www.semtech.com protection products LC04-12 dual low capacitance tvs array for telecom line-card applications ? transient protection for high-speed data lines to bellcore gr 1089 i pp =100a (2/10s) itu k.20 i pp =100a (5/310s) iec 61000-4-2 (esd) 15kv (air), 8kv (contact) iec 61000-4-4 (eft) 40a (5/50ns) iec 61000-4-5 (lightning) i pp =100a (8/20s) ? protects two tip and ring line pairs ? low capacitance for high-speed interfaces ? high surge capability ? low clamping voltage ? solid-state silicon avalanche technology description features circuit diagram schematic & pin configuration revision 01/15/03 applications mechanical characteristics so-16 (top view) ? jedec so-16 package ? molding compound flammability rating: ul 94v-0 ? marking : part number, date code, logo ? packaging : tube or tape and reel per eia 481 ? adsl/hdsl ? rs-232 and rs-423 ? v.90 ? wan/lan equipment ? cable modems tip ring pin 1 - 4 pin 13 - 16 the LC04-12 has been specifically designed to protect sensitive components which are connected to high- speed telecommunications lines from over voltages caused by lightning, electrostatic discharge (esd) , cable discharge event (cde) , and electrical fast tran- sients (eft) . the device is in a jedec so-16 nb package. it is designed to provide metallic (tip to ring) or common mode (tip to ground and ring to ground) surge protec- tion for up to two tip and ring pairs. the low capaci- tance topology means signal integrity is preserved on high-speed lines. the high surge capability (600w, tp=10/1000s) makes the LC04-12 suitable for telecommunications systems operating in harsh tran- sient environments. the LC04-12 is designed to meet the lightning surge requirements of bellcore gr- 1089(intra-building), itu k.20, and iec 61000-4-5. the features of the LC04-12 are ideal for protecting adsl, rs-232, rs-423, rs-422, and v.90 interfaces.
2 ? 2003 semtech corp. www.semtech.com protection products LC04-12 absolute maximum rating electrical characteristics g n i t a rl o b m y se u l a vs t i n u t ( r e w o p e s l u p k a e p p ) s 0 0 0 1 / 0 1 =p k p 0 0 6s t t a w t ( t n e r r u c e s l u p k a e p p 1 = 0 0 0 1 / 0) si p p 5 2a t ( t n e r r u c e s l u p k a e p p ) s 0 2 / 8 =i p p 0 0 1a e r u t a r e p m e t g n i r e d l o s d a e lt l ) . c e s 0 1 ( 0 6 2c e r u t a r e p m e t g n i t a r e p ot j 5 2 1 + o t 5 5 -c e r u t a r e p m e t e g a r o t st g t s 0 5 1 + o t 5 5 -c 2 1 - 4 0 c l r e t e m a r a pl o b m y ss n o i t i d n o cm u m i n i ml a c i p y tm u m i x a ms t i n u e g a t l o v f f o - d n a t s e s r e v e rv m w r 2 1v e g a t l o v n w o d k a e r b e s r e v e rv r b i t a m 1 =3 . 3 1v t n e r r u c e g a k a e l e s r e v e ri r v m w r c 5 2 = t , v 2 1 =2a e g a t l o v g n i p m a l cv c i p p , a 0 1 = t p s 0 0 0 1 / 0 1 = 5 . 9 1v e g a t l o v g n i p m a l cv c i p p , a 5 2 = t p s 0 0 0 1 / 0 1 = 4 2v e c n a t i c a p a c n o i t c n u jc j e n i l h c a e v r z h m 1 = f , v 0 = 5 1f p
3 ? 2003 semtech corp. www.semtech.com protection products protection products LC04-12 typical characteristics non-repetitive peak pulse power vs. pulse time power derating curve clamping voltage vs. peak pulse current 0 10 20 30 40 50 60 70 80 90 100 110 0 5 10 15 20 25 30 time (s) percent of i pp e -t td = i pp /2 waveform parameters: tr = 8s td = 20s pulse waveform clamping voltage vs. peak pulse current 0.1 1 10 100 0.1 1 10 100 1000 pulse duration - t p (s) peak pulse power - p pk (kw) 0 5 10 15 20 25 0 20 40 60 80 100 120 140 160 peak pulse current - i pp (a) clamping voltage - v c (v) waveform parameters: tr = 8s td = 20s 0 5 10 15 20 25 30 0 5 10 15 20 25 30 peak pulse current - i pp (a) clamping voltage - v c (v) waveform parameters: tr = 10s td = 1000s 0 10 20 30 40 50 60 70 80 90 100 110 0 25 50 75 100 125 150 ambient temperature - t a ( o c) % of rated power or i pp capacitance vs. reverse voltage 0 2 4 6 8 10 12 14 01234567 reverse voltage - v r (v) capacitance - c j (pf) f=1mhz
4 ? 2003 semtech corp. www.semtech.com protection products LC04-12 figure 1 - connection for differential (line-to-line) protection of two tip/ring line pairs t ip 1 t ip 2 ring 1 ring 2 device connection options the LC04-12 is designed to protect up to four high- speed data lines (two differential pairs) from transient over-voltages which result from lightning and esd. differential protection of two line pairs is achieved by connecting the device as follows (figure 1): pins 1-4 are connected to line 1 of the first pair (i.e. tip 1) and pins 13-16 are connected to line 2 of the first pair (i.e. ring 1). pins 5-8 are connected to line 1 of the second pair (i.e. tip 2) and pins 9-12 are connected to line 2 of the second pair (i.e. ring 2). common mode protection of one line pair is achieved by connecting the device as shown in figure 2. the protected lines are connected at pins 1-4 and pins 9- 12. connection to ground is made at pins 5-8 and 13- 16. optionally, the lines may be connected at pins 1-4 and 5-8 with pins 9-16 being connected to ground. all pins should be connected for best results. minimize parasitic inductance in the protection circuit path by keeping the trace length between the protected line and the LC04-12 as short as possible. ground con- nections should be made directly to the ground plane. adsl protection configuring the LC04-12 for remote terminal adsl applications a typical adsl protection circuit for remote terminals is shown in figure 3. the LC04-12 is connected between tip & ring on the transmit and receive line pairs. it provides protection to common mode (line-to-ground) lightning and esd surges. it is designed to meet the intra-building requirements of bellcore gr-1089. to complete the protection circuit, the lcda12c-1 is employed as the ic side protection element. this device helps prevent the transceiver from latching up by providing fine clamping of transients that are coupled through the transformer. figure 2 - connection for common mode (line-to- ground) protection of one tip/ring line pair tip g nd gnd ring applications information
5 ? 2003 semtech corp. www.semtech.com protection products protection products LC04-12 configuring the LC04-12 for central office adsl applications for central office applications, the LC04-12 can be configured for operation to 24v with the addition of two external steering diodes. this is accomplished by connecting two adjacent legs of the LC04-12 in series and adding the steering diodes as shown in figure 4. each of the tvs diodes has a working voltage of 12v. since the voltages are additive when series connected, the device will have a working voltage of 24v. the power rating of the device is effectively doubled since the surge current capability remains unchanged. during positive duration transients, the internal tvs diodes of the LC04-12 will be reversed biased when the line voltage exceeds 24v. transient current will flow through the LC04-12 to ground. for negative duration transient, the external steering diodes (d1 and d2) will be forward biased when the voltage exceeds the forward voltage (v f ) of the device. the steering diodes are required to insure that the internal compensation diodes of the LC04-12 are not reverse biased as this would result in their destruction. the es1a ultrafast rectifiers have been found to work well in this application. these devices will survive the bellcore 1089 (intra-building) and itu k.20/k.21 surges and have a repetitive reverse voltage rating of 50v, and a typical junction capacitance of 10pf. the total capacitance seen by the line will typically be <25pf. this is determined by the sum of the capaci- tance of the steering diode and 1/2 of the capacitance of each line pair of the LC04-12. applications information (continued)
6 ? 2003 semtech corp. www.semtech.com protection products LC04-12 typical applications figure 3 - adsl protection (remote terminal) figure 4- LC04-12 configured for 24v lines (adsl central office) t n e n o p m o ct n e n o p m o c t n e n o p m o c t n e n o p m o ct n e n o p m o ct r a pt r a p t r a p t r a pt r a p r e b m u nr e b m u n r e b m u n r e b m u nr e b m u n n o i t p i r c s e dn o i t p i r c s e d n o i t p i r c s e d n o i t p i r c s e dn o i t p i r c s e d s v t2 1 - 4 0 c le c n a t i c a p a c w o l y a r r a e d o i d s v t 2 d & 1 da 1 s ee c a f r u s t s a f a r t l u r e i f i t c e r t n u o m
7 ? 2003 semtech corp. www.semtech.com protection products protection products LC04-12 land pattern - so-16 outline drawing - so-16
8 ? 2003 semtech corp. www.semtech.com protection products LC04-12 contact information semtech corporation protection products division 200 flynn road, camarillo, ca 93012 phone: (805)498-2111 fax (805)498-3804 t r a p r e b m u n g n i k r o w e g a t l o v r e p y t q l e e r e z i s l e e r b t . 2 1 - 4 0 c lv 2 10 0 5h c n i 7 e t . 2 1 - 4 0 c lv 2 10 0 5 2h c n i 3 1 note: (1) no suffix indicates tube pack. ordering information
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