ESDAXXL ? march 1998 - ed: 3 dual transil ? array for esd protection sot23 where transient overvoltage protection in esd sensitive equipment is required, such as : - computers - printers - communication systems it is particulary recommended for the rs232 i/o port protection where the line interface withstands only with 2kv esd surges. applications application specific discretes a.s.d. ? functional diagram 2 unidirectional transil ? functions. low leakage current : i r max. < 20 m s. 300 w peak pulse power (8/20 m s) features description the ESDAXXL is a dual monolithic voltage suppressor designed to protect componentswhich are connected to data and transmission lines against esd. it clamps the voltage just above the logic level supply for positive transients, and to a diode drop below ground for negative transients. it can also work as bidirectionnal suppressor by connecting only pin1 and 2. benefits high esd protection level : up to 25 kv. high integration. suitable for high density boards. iec 1000-4-2 level 4 mil std 883c-method 3015-6 : class 3. (human body model) complies with the following standards : 1/6
symbol parameter v rm stand-off voltage v br breakdown voltage v cl clamping voltage i rm leakage current i pp peak pulse current a t voltage temperature coefficient c capacitance rd dynamic resistance v f forward voltage drop electrical characteristics (t amb =25 c) symbol parameter value unit v pp electrostatic discharge mil std 883c - method 3015-6 25 kv p pp peak pulse power (8/20 m s) 300 w t stg t j storage temperature range maximum junction temperature - 55 to + 150 150 c c t l maximum lead temperature for soldering during 10s 260 c t op operating temperature range - 40 to + 85 c absolute maximum ratings (t amb =25 c) types v br @i r i rm @v rm rd a tc v f @i f min. max. max. typ. max. typ. max. note 1 note 2 0v bias vvma m avm w 10 -4 / cpf v ma esda6v1l 6.1 7.2 1 20 5.25 350 6 140 1.25 200 esda14v2l 14.2 15.8 1 5 12 650 10 90 1.25 200 note 1 : square pulse ipp = 15a, tp=2.5 m s. note 2 : d v br = a t* (tamb -25 c) * v br (25 c) ? ESDAXXL 2/6
the esda family has been designed to clamp fast spikes like esd. generally the pcb designers need to calculate easily the clamping voltage v cl . this is why we give the dynamic resistance in addition to the classical parameters. the voltage across the protection cell can be calculated with the following formula: v cl =v br +rdi pp whereipp is the peakcurrent throughthe esdacell. dynamic resistance measurement the short duration of the esd has led us to prefer a more adapted test wave, as below defined, to the classical 8/20 m s and 10/1000 m s surges. 2.5 m s duration measurement wave. as the value of the dynamic resistance remains stable for a surge duration lower than 20 m s, the 2.5 m s rectangular surge is well adapted. in addition both rise and fall times are optimized to avoid any parasitic phenomenon during the measurement of rd. calculation of the clamping voltage use of the dynamic resistance 2 m s tp = 2.5 m s t i ipp 0 25 50 75 100 125 150 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 ppp[tj initial]/ppp[tj initial=25 c] tj initial( c) fig. 1 : peak power dissipation versus initial junction temperature 1 10 100 10 100 1000 3000 ppp(w) tp( m s) fig. 2 : peak pulse power versus exponential pulse duration (tj initial = 25 c) ? ESDAXXL 3/6
25 50 75 100 125 1 10 100 200 i [tj] / i [tj=25 c] rr tj( c) fig. 5 : relative variation of leakage current versus junction temperature (typical values). 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 0.01 0.10 1.00 5.00 i (a) fm tj=25 c v (v) fm fig. 6-1 : peak forward voltage drop versus peak forward current (typical values)(esda6v1l). 0 5 10 15 20 25 30 35 40 45 50 0.1 1.0 10.0 50.0 i (a) pp tp=2.5 m s esda6v1l esda14v2l v (v) cl fig. 3 : clamping voltage versus peak pulse current (tj initial = 25 c). rectangular waveform tp = 2.5 m s. 12 51020 10 20 50 100 200 c(pf) f=1mhz vosc=30mv esda6v1l esda14v2l v (v) r fig. 4 : capacitanceversus reverse applied voltage (typical values). 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 0.01 0.10 1.00 5.00 i (a) fm tj=25 c v (v) fm fig. 6-2 : peak forward voltage drop versus peak forward current (typical values)(esda14v2l). ? ESDAXXL 4/6
typical application : esd sensitive device gnd 2 * ESDAXXL i/o i/o i/o i/o application example 1. esd protection by the ESDAXXL electrostatic discharge (esd) is a major cause of failure in electronic systems. transient voltage suppressors (tvs) are an ideal choice for esd protection. they are capable of clamping the incoming transient to a low enough level such that damage to the protected semiconductor is prevented. surface mount tvs arrays offer the best choice for minimal lead inductance. they serve as parallel protection elements, connected between the signal line to ground. as the transient rises above the operating voltage of the device, the tvs array becomes a low impedance path diverting the transient current to ground. the ESDAXXL array is the ideal board level protection of esd sensitive semiconductor components. the tiny sot23 package allows design flexibility in the design of high density boards where the space saving is at a premium. this enablesto shorten the routing and contributes to hardening againt esd. 2. circuit board layout circuit board layout is a critical design step in the suppression of esd induced transients. the following guidelines are recommended : the ESDAXXL should be placed as close as pos- sible to the input terminals or connectors. the path length between the esd suppressor and the protected line should be minimized all conductive loops, including power and ground loops should be minimized the esd transient return path to ground should be kept as short as possible. ground planes should be used whenever possi- ble. ? ESDAXXL 5/6
type marking esda6v1l el61 esda14v2l el15 packaging: standard packaging is tape and reel. marking information furnished is believed to be accurate and reliable. however, sgs-thomson micr oelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. no license is granted by implication or otherwise under any patent or patent rights of sgs-thomson microelectronics. specifications mentioned in this publication are subject to change without notice. this publication supersedes and replaces all information previously supplied. sgs- thomson microelectronics products are not authorized for use as critical components in life support devices or systems without express writ- ten approval of sgs-thomson microelectronics. ? 1998 sgs-thomson microelectronics - printed in italy - all rights reserved. sgs-thomson microelectronics group of companies australia - brazil - canada - china - france - germany - italy - japan - korea - malaysia - malta - morocco the netherlands - singapore - spain - sweden - switzerland - taiwan - thailand - united kingdom - u.s.a. package mechanical data sot23 (plastic) b e s e e1 a d c l h a1 ref. dimensions millimeters inches min. max. min. max. a 0.64 1.3 0.025 0.051 a1 0.1 0.004 b 0.3 0.54 0.012 0.021 c 0.085 0.18 0.003 0.007 d 2.67 3.05 0.105 0.120 e 0.89 1.05 0.035 0.041 e1 1.7 2.1 0.067 0.083 e 1.2 1.6 0.047 0.063 h 2.1 2.75 0.083 0.108 s 0.35 0.65 0.014 0.026 foot print (in millimeters) 0.9 0.035 0.9 0.035 1.9 0.075 mm inch 2.35 0.92 1.1 0.043 1.1 0.043 1.45 0.037 0.9 0.035 order code esda 6v1 l esd array v br min package : sot23 plastic ? ESDAXXL 6/6
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