? 1999 calirornia micro devices corp. all rights reserved. 11/99 215 topaz street, milpitas, california 95035 tel: (408) 263-3214 fax: (408) 263-7846 www.calmicro.com california micro devices pac dn016 diode forward dc current (note 1) 20ma storage temperature -65c to 150c operating temperature range -20c to 85c dc voltage at any channel input v n -0.5v to v p +0.5v note 1: only one diode conducting at a time. 6 channel esd protection array with zener supply clamp features ? six channels of esd protection ? integral zener diode clamp to suppress supply rail transient ? 15kv esd protection (hbm) ? 8kv contact, 15kv air esd protection per iec 61000-4-2 ? low loading capacitance, 3pf typ ? miniature 8-pin msop or soic package product description the pac? dn016 is a diode array designed to provide 6 channels of esd protection for electronic components or sub- systems. each channel consists of a pair of diodes which steers the esd current pulse either to the positive (v p ) or negative (v n ) supply. in addition, there is an integral zener diode between v p and v n to suppress any voltage disturbance due to these esd current pulses. the pac dn016 will protect against esd pulses up to 15kv human body model, and 8kv contact discharge per international standard iec 61000-4-2. applications ? i/o port protection for cellular phones, notebook computers, pdas, etc. ? esd protection for vga (video) port in pc?s or notebook computers. ? esd protection for sensitive electronic equipment. absolute maximum ratings schematic configuration note 2: from i/o pins to v p or v n only. bypass opacitor between v p and v n is not required. however, a 0.2 f ceramic chip capacitor bypassing v p to v n is recommended if the lowest possible channel clamp voltage is desired. note 3: human body model per mil-std-883, method 3015, c discharge =100pf, r discharge =1.5k w , v p =5.0v, v n =gnd. note 4: this parameter is guaranteed by design and characterization. note 5: standard iec 61000-4-2 with c discharge =150pf, and r discharge =330 w , v p =5v, v n =gnd. 1 c0540399 pac? is a trademark of california micro devices corp. s n o i t a c i f i c e p s d r a d n a t s r e t e m a r a p. n i m. p y t. x a m e g a t l o v y l p p u s g n i t a r e p ov ( p v - n )v 5 . 5 @ t n e r r u c y l p p u sv p v - n v 5 . 5 = a 0 2 i , e g a t l o v d r a w r o f e d o i d f c 5 2 = t , a m 0 2 =v 5 6 . 0v 5 9 . 0 c 5 2 = t , a m 1 @ e g a t l o v n w o d k a e r b e s r e v e r p m a l c r e n e z v 6 . 6 n o i t c e t o r p d s e m e t s y s - n i , t u p n i l e n n a h c y n a t a e g a t l o v e g r a h c s i d k a e p ) 2 e t o n ( 0 0 0 5 1 0 3 d o h t e m , l e d o m y d o b n a m u h ) 4 , 3 e t o n ( v k 5 1 0 0 0 2 - 4 - 0 0 0 1 6 c e i r e p e g r a h c s i d t c a t n o c ) 5 e t o n ( v k 8 c 5 2 = t , m b h d s e v k 5 1 @ e g a t l o v p m a l c l e n n a h c ) 4 , 3 s e t o n ( 0 0 0 s t n e i s n a r t e v i t i s o p 0 0 0 s t n e i s n a r t e v i t a g e n v p +v 0 . 3 1 v n -v 0 . 3 1 c 5 2 = t , t n e r r u c e g a k a e l l e n n a h c a 1 . 0 a 0 . 1 ) z h m 1 @ d e r u s a e m ( e c n a t i c a p a c t u p n i l e n n a h c v p v , v 5 = n , v 0 =v t u p n i v 5 . 2 = ) 4 e t o n ( f p 3f p 6 g n i t a r r e w o p e g a k c a p 0 0 0 e g a k c a p c i o s 0 0 0 e g a k c a p p o s m w m 0 5 3 w m 0 0 2 this device is particularly well-suited for portable electronics (e.g. cellular phones, pdas, notebook computers) because of its small package footprint, high esd protection level, and low loading capacitance. it is also suitable for protecting video output lines and i/o ports in computers and peripheral equipment.
?1999 california micro devices corp. all rights reserved. 11/99 215 topaz street, milpitas, california 95035 tel: (408) 263-3214 fax: (408) 263-7846 www.calmicro.com california micro devices pac dn016 application information see also california micro devices application note ap209, ?design considerations for esd protection.? in order to realize the maximum protection against esd pulses, care must be taken in the pcb layout to minimize parasitic series inductances to the supply and ground rails. refer to figure 1, which illustrates the case of a positive esd pulse applied between an input channel and chassis ground. the parasitic series inductance back to the power supply is represented by l 1 . the voltage v z on the line being protected is: v z = forward voltage drop of d 1 + l 1 x d(i esd )/dt + v supply where i esd is the esd current pulse, and v supply is the positive supply voltage. an esd current pulse can rise from zero to its peak value in a very short time. as an example, a level 4 contact discharge pe r the iec 61000-4-2 standard results in a current pulse that rises from zero to 30 amps in 1ns. here d(i esd )/dt can be approximated by d i esd / d t, or 30/(1x10 -9 ). so just 10nh of series inductance (l 1 ) will lead to a 300v increment in v z ! figure 1 2 input capacitance vs. input voltage 0 1 2 3 4 5 012345 input voltage input capacitance (pf ) typical variation of c in with v in (v p =5v, v n =0v) n o i t a m r o f n i g n i r e d r o t r a p d r a d n a t s e g a k c a pr e b m u n t r a p g n i r e d r o s n i pe l y t sg n i k r a m t r a p 8c i o ss 6 1 0 n d c a p 8p o s mm 6 1 0 n d c a p when placing an order please specify desired shipping: tubes or tape & reel. (v p = 5v, v n = 0v, 0.1 m f chip capacitor between v p & v n )
? 1999 calirornia micro devices corp. all rights reserved. 11/99 215 topaz street, milpitas, california 95035 tel: (408) 263-3214 fax: (408) 263-7846 www.calmicro.com california micro devices pac dn016 figure 5 4 8/99 similarly for negative esd pulses, parasitic series inductance from the v n pin to the ground rail will lead to drastically increased negative voltage on the line being protected. another consideration is the output impedance of the power supply for fast transient currents. most power supplies exhibit a much higher output impedance to fast transient current spikes. in the v z equation above, the v supply term, in reality, is given by (v dc + i esd x r out ), where v dc and r out are the nominal supply dc output voltage and effective output impedance of the power supply respectively. as an example, a r out of 1 ohm would result in a 10v increment in v z for a peak i esd of 10a. to mitigate these effects, a zener diode has been integrated into this protection array between v p and v n . this zener diode clamps the maximum voltage of v p relative to v n at the breakdown voltage of the zener diode. although not strictly necessary, it is recommended that v p be bypassed to the ground plane with a high frequency bypass capacitor. this will lower the channel clamp voltage, and is especially effective when v p is much lower than the zener breakdown voltage. the value of this bypass capacitor should be chosen such that it will absorb the charge transferred by the esd pulse with minimal change in v p . typically a value in the 0.1 f to 0.2 f range is adequate for iec-61000-4-2 level 4 contact discharge protection (8kv). for higher esd voltages, the bypass capacitor should be increased accordingly. ceramic chip capacitors mounted with short printed circuit board traces are good choices for this application. electrolytic capacitors should be avoided as they have poo r high frequency characteristics. as a general rule, the esd protection array should be located as close as possible to the point of entry of expected electrosta tic discharges. the power supply bypass capacitor mentioned above should be as close to the v p pin of the protection array as possible, with minimum pcb trace lengths to the power supply and ground planes to minimize stray series inductance.
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