2-97 hermetic pin diodes for stripline/microstrip switches/ attenuators technical data features ? broadband operation hf through x-band ? low insertion loss less than 0.5 db to 10 ghz (5082-3140) ? high isolation greater than 20 db to 10 ghz (5082-3140) ? fast switching/modulation 5 ns typical (5082-3141) ? low drive current required less than 20 ma for 20 db isolation (5082-3141) description/applications the hp 5082-3140 is a passivated planar device and the 5082-3141 is a passivated mesa device. both are in a shunt configuration in hermetic stripline packages. these diodes are optimized for good continuity of characteristic impedance which allows a continuous transition when used in 50 w microstrip or stripline circuits. these diodes are designed for applications in microwave and hf-uhf systems using stripline or microstrip transmission line techniques. 5082-3140 5082-3141 outline 60 6.65 (0.262) 6.15 (0.242) 0.64 typ. (0.025) 1.52 typ. (0.060) dimensions in millimeters and (inches) dia. (2 places) 3.05 min. (0.120) 0.13 typ. (0.005) 2.03 typ. chip location (0.080) 4.19 (0.165) 3.94 (0.155) 5.46 (0.215) 4.95 (0.195) 10.67 (0.420) 10.16 (0.400) 2.16 (0.085) 1.91 (0.075) 3.18 (0.125) 2.95 (0.115) 2.54 (0.100) 2.34 (0.092) maximum ratings part no. 5082- -3140 -3141 junction operating and storage -65 c to -65 c to temperature range +150 c +150 c power dissipation [1] 1.75 w 0.75 w peak incident pulse power [2] 225 w 50 w peak inverse voltage 150 v 70 v soldering temperature 230 c for 5 sec. notes: 1. device properly mounted in sufficient heat sink at 25 c, derate linearly to zero at maximum operating temperature. 2. t p = 1 m s, f = 10 ghz, du = 0.001, z o = 50 w , t a = 25 c. 5965-8882e
2-98 typical circuit functions per- formed consist of switching, duplexing, multiplexing, leveling, modulating, limiting, or gain control functions as required in tr switches, pulse modulators, phase shifters, and amplitude modulators operating in the frequency range from hf through ku-band. these diodes provide nearly ideal transmission characteristics from hf through ku-band. mechanical specifications package outline 60 is hermetic- ally sealed and capable of meeting the stringent requirements of space level high reliability testing. both the package and lead materials are gold plated kovar. the 5082-3141 is recommended for applications requiring fast switching or high frequency modulation of microwave signals, or where the lowest bias current for maximum attenuation is required. more information is available in hp application note 922 (applica- tions of pin diodes) and 929 (fast switching pin diodes). electrical specifications at t a = 25 c max. typical max. reverse typical cw power part min. insertion recovery carrier switching number package heat isolation loss max. time lifetime capability 5082- outline sink (db) (db) swr t rr (ns) t (ns) p a (w) 3140 60 anode 20 0.5 1.5 C 400 30 3141 60 cathode 20 1.0 1.5 10 35* 13 test [1] CCi f = 100 ma i f = 0 i f = 0 i f = 20 ma i f = 50 ma C conditions (except 3141; p in = 1 mw p in = 1 mw v r = 10 v i r = 250 ma i f = 20 ma) recovery *i f = 10 ma to 90% *i r = 6 ma note: 1. test frequencies: 8 ghz 5082-3141; 10 ghz 5082-3140. equivalent circuits z o = 50 z o = 50 l p l p r p r p forward bias (isolation state) zero bias (insertion loss state) r s l 1 e r = 1 e r = 1 1 2 z o = 50 z o = 50 l p l p r p r p c t r 1 e r = 1 e r = 1 1 r 2 l 2 2
2-99 forward voltage (v) forward current (ma) frequency (ghz) figure 2. typical insertion loss vs. frequency. 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0 insertion loss (db) 24 6 810 100 10 1 0.1 0.01 0 0.2 0.4 0.6 0.8 1.0 1.2 forward current (ma) forward voltage (v) figure 1. typical forward characteristics. 3140 125 c 25 c ?0 c 100 10 1 0.1 0.01 0 0.2 0.4 0.6 0.8 1.0 1.2 3141 125 c 25 c ?0 c 3141 3140 frequency (ghz) figure 3. typical swr vs. frequency. 1.8 1.6 1.4 1.2 1.0 swr 24 6 810 both diodes frequency (ghz) figure 4. typical isolation vs. frequency. 34 32 30 28 26 24 22 20 18 isolation (db) 24 6 810 3141 3140 bias current (ma) figure 5. typical attenuation above zero bias insertion loss vs. bias current at f = 8 ghz. 100 10 1 0.1 attenuation (db) 0.001 0.01 0.1 1 100 10 3141 3140 typical parameters typical equivalent circuit parametersCforward bias part number lp rp rs l 1 1 2 5082- (ph) ( w )( w ) (ph) (mm) (mm) 3140 150 0.0 0.95 30 3.8 3.8 3141 150 0.0 0.8 20 3.8 3.8 typical equivalent circuit parametersCzero bias part number lp rp r 1 l 2 r 2 c t 1 2 5082- (ph) ( w )(k w ) (ph) (k w ) (pf) (mm) (mm) 3140 30 0.0 1.2 16 0.0 0.20 5.3 5.3 3141 200 0.0 0 0.4 0.14 4.4 4.4
2-100 typical switching parameters rf switching speed hp 5082-3141 the rf switching speed of the hp 5082-3141 may be considered in terms of the change in rf isola- tion at 2 ghz. this switching speed is dependent upon the forward bias current, reverse bias drive pulse, and characteristics of the pulse source. the rf switch- ing speed for the shunt-mounted stripline diode in a 50 w system is considered for two cases, one driving the diode from the for- ward bias state to the reverse bias state (isolation to insertion loss), second driving the diode from the reverse bias state to the forward bias state (insertion loss to isolation). the total time it takes to switch the shunt diode from the isolation state (forward bias) to the inser- tion loss state (reverse bias) is shown in figure 6. these curves are for three forward bias condi- tions with the diode driven in each case with three different reverse voltage pulses (v pr ). the total switching time for each case includes the delay time (pulse initiation to 20 db isolation) and transition time (20 db isolation to 0.9 db isolation). slightly faster switching times may be realized by spiking the leading edge of the pulse or using a lower impedance pulse driver. time (ns) 28 24 20 16 12 8 4 0 isolation (db) 024681002468100246810 power = 0 dbm f o = 2 ghz i f = 10 ma i f = 20 ma i f = 50 ma 10 v 5v 2v figure 6. isolation vs. time (turn-on) for hp 5082-3141. frequency, 2 ghz. the time it takes to switch the diode from zero or reverse bias to a given isolation is less than the time from isolation to the insertion loss case. for all cases of forward bias generated by the pulse generator (positive pulse), the rf switching time from the insertion loss state to the isola- tion state was less than 2 nano- seconds. a more detailed treatise on switching speed is published in an929: fast switching pin diodes. reverse recovery time figures 8 and 9 show reverse recovery time, (t rr ) vs. forward current, (i f ) for various reverse pulse voltages v r . the circuit used to measure t rr is shown in figure 7. 50 50 1.5 f 1.0 f 1.0 k d.u.t. to scope v r i f figure 7. basic t rr test setup. 30 15 20 25 10 5 0 0102030 reverse recovery time (ns) forward current (ma) figure 8. typical reverse recovery time vs. forward current for various reverse driving voltages, 5082-3141. v r = 2 v v r = 10 v v r = 5 v 1000 100 10 0102030 reverse recovery time (ns) forward current (ma) figure 9. typical reverse recovery time vs. forward current for various reverse driving voltages, 5082-3140. v r = 5 v v r = 20 v v r = 10 v
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