data sheet february 1999 LG1627BXC clocked laser driver features n high data-rate clocked laser diode driver n clock disable mode for data feedthrough n adjustable high output current n operation up to 3 gbits/s applications n sonet/sdh transmission systems n sonet/sdh test equipment n optical transmitters functional description the LG1627BXC is a g allium arsenide ( gaas ) laser diode driver to be used with direct modulated laser diodes in hi g h-speed non-return-to-zero ( nrz ) trans- mission s y stems. the device is made in a hi g h- performance 0.9 m g ate gaas hetero- j unction fet technolo gy that utilizes hi g h-densit y mim capacitors, airbrid g e interconnect, and nicr film precision resis- tors. the driver includes differential data and clock inputs. the hi g h-output, low overshoot drive current and prebias can be set separatel y . data retimin g is accomplished b y the internal flip-flop, minimizin g j itter on the data. clockin g can be disabled for data feedthrou g h. a pulse-width control enables the user to compensate for laser turn-on dela y . a 2.5 v band- g ap reference is re q uired for stable operation over temperature and var y in g power suppl y volta g e. functional diagram 5-6549(f).b figure 1. functional diagram bg2p5 pwp mod_e pwn gnd i out mk mk v ss1 clk_e clk clk v in v in v th v ss2 v ss3 v mod v pre i out-pre LG1627BXC
data sheet LG1627BXC clocked laser driver february 1999 2 lucent technologies inc. block diagram 5-7675(f)r.1 figure 2. block diagram v pre v mod mk mk gnd pwn pwp clk_e dq v th 50 w v in v in clk clk 50 w 50 w 50 w v ss1 bg2p5 mod_e v ss3 v ss2 22 w gnd i out i out-pr e
data sheet february 1999 LG1627BXC clocked laser driver 3 lucent technologies inc. pin information 5-6551(f).br.3 figure 3. pin diagram table 1. pin descriptions * national semiconductor is a registered trademark of national semiconductor corporation. pin symbol description 1v th capacitor to g round ( data input reference ) . 2v in data input. 3 complementar y data input. 4, 13, 14, packa g e bottom gnd ground. for optimum performance, the packa g e bottom must be soldered to the g round plane. 5 clk clock input. 6clk complementar y clock input. 7bg2p5 - 2.5 v band- g ap reference ( national semiconductor * p/n lm4040 ) . 8 mod_e modulation enable ( connect to v ss1 to enable, float to disable ) . 9 pwp pulse width ad j ust positive. 10 pwn pulse width ad j ust ne g ative. 11 mk complementar y mark densit y output. 12 mk mark densit y output. 15, 16 i out output modulation current ( dc coupled to laser cathode ) . 17 i out-pre output prebias current. 18 v pre prebias control input. 19 v ss2 v ss2 suppl y - 5.2 v for output prebias. 20 v ss3 v ss3 suppl y - 5.2 v for output modulation. 21 v mod modulation current control input. 22, 23 v ss1 v ss1 suppl y - 5.2 v. 24 clk_e clock enable ( connect to v ss1 to enable, float to disable ) . gnd gnd i out i out i out-pre v pre v ss2 v ss3 v mod v ss1 v ss1 clk_e bg2p5 mod_e pwp pwn mk mk v th v in gnd clk clk v in 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 v in
data sheet LG1627BXC clocked laser driver february 1999 4 lucent technologies inc. absolute maximum ratings stresses in excess of the absolute maximum ratings can cause permanent damage to the device. these are abso- lute stress ratings only. functional operation of the device is not implied at these or any other conditions in excess of those given in the operational sections of the data sheet. exposure to absolute maximum ratings for extended periods can adversely affect device reliability. recommended o p eratin g conditions table 3. recommended operating conditions handling precautions although protection circuitry has been designed into this device, proper precautions should be taken to avoid expo- sure to electrostatic discharge (esd) during handling and mounting. lucent employs a human-body model (hbm) and a charged-device model (cdm) for esd-susceptibility testing and protection design evaluation. esd voltage thresholds are dependent on the circuit parameters used to define the model. no industry-wide standard has been adopted for the cdm. however, a standard hbm (resistance = 1500 w , capacitance = 100 pf) is widely used and, therefore, can be used for comparison. the hbm esd threshold presented here was obtained by using these cir- cuit parameters. table 4. esd threshold voltage mountin g and connections certain precautions must be taken when usin g solder. for installation usin g a constant temperature solder, temper- atures of under 300 c ma y be emplo y ed for periods of time up to 5 seconds, maximum. for installation with a sol- derin g iron ( batter y operated or nonswitchin g onl y) , the solderin g tip temperature should not be g reater than 300 c and the solderin g time for each lead must not exceed 5 seconds. this device is supplied with solder on the back of the packa g e. for optimum performance, it is recommended to solder the back of the packa g e to g round. table 2. absolute maximum ratings parameter symbol min max unit supply voltage v ss C5.7 v input voltage v i gnd v ss v power dissipation p d 1 w storage temperature t stg - 40 125 c operating case temperature range t c 0 100 c parameter symbol min max unit case temperature t case 070c power supply v ss C4.7 C5.7 v human-body model esd threshold device voltage LG1627BXC >200
data sheet february 1999 LG1627BXC clocked laser driver 5 lucent technologies inc. electrical characteristics (t a = 25 c, v ss1 = v ss2 = v ss3 = C5.2 v, data input = 600 mv (single ended), and r l = 50 w ) minimum and maximum values are testing requirements. typical values are characteristics of the device and are the result of engineering evaluations. typical values are for information purposes only and are not part of the test- ing requirements. stresses in excess of the absolute maximum ratings can cause permanent damage to the device. table 5. electrical characteristics 1. excludes i pre and avera g e i mod . power suppl y current i ss2 ( relatin g to prebias ) is dependent on v pre . power suppl y current i ss3 ( relatin g to modulation ) is dependent on v mod . 2. maximum modulation at maximum v mod . 3. maximum prebias at maximum v pre . parameter symbol min typ max unit data input volta g e, sin g le ended v in 300 600 1000 mv power suppl y volta g ev ss1 , v ss2 , v ss3 C 4.9 C 5.2 C 5.5 v power suppl y current 1 i ss1 100 140 160 ma volta g e control for output modulation current v mod C 4.0 C 5.5 v output minimum modulation current i out low 02ma output maximum modulation current 2 i out high 75 85 ma volta g e control for prebias current v pre C 3.0 C 5.5 v output minimum prebias current i pre low 00.5ma output maximum prebias current 3 i pre high 50 60 ma mark densit y , 50% dut y c y cle ( 1 k w to gnd ) mk C 0.5 v mark densit y complement, 50% dut y c y cle ( 1 k w to gnd ) mk C 0.5 v pulse width ad j ust plus pwp C 3.0 C 4.2 C 5.5 v pulse width ad j ust ne g ative pwn C 3.0 C 4.2 C 5.5 v out p ut modulation i out = 40 ma, clock enabled output rise and fall times ( 20% 80% ) t r , t f 90 ps jitter ( rms ) 4 ps phase mar g in 270 de g out p ut modulation i out = 40 ma, clock disabled output rise and fall times ( 20% 80% ) t r , t f 90 ps jitter ( rms ) 6 ps out p ut modulation i out = 80 ma, clock enabled output rise and fall times ( 20% 80% ) t r , t f 100 ps jitter ( rms ) 4 ps phase mar g in 270 de g out p ut modulation i out = 80 ma, clock disabled output rise and fall times ( 20% 80% ) t r , t f 100 ps jitter ( rms ) 6 ps
data sheet LG1627BXC clocked laser driver february 1999 6 lucent technologies inc. typical optical evaluations and performance characteristics 5-7693(f)r.3 notes: all b y pass capacitors should be mounted close to the packa g e. for optimum performance, the packa g e must be soldered to g round. mark densit y ( mk and mk ) outputs are terminated with 1 k w pull-up resistors. for sin g le-ended operation, unused data and clock inputs should be ac coupled to a 50 w termination. pin 13 and pin 14 should be tied to g ether with a separate path to the g round plane. figure 4. typical optical evaluation of the LG1627BXC and d2500 laser zo = 50 w clock 0.047 m f clk voltage divider current sense v ss1 bypass 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 LG1627BXC clocked laser driver zo = 50 w data v ss1 v ss3 v mod 0.1 m f v ss = C5.2 v 0.047 m f 1 k w 1 k w mk mk clk_e v in i out v ss2 i out-pre v pre voltage divider current sense zo = 25 w 1 2 3 4 5 6 7 14 13 12 11 10 9 8 d2500 laser laser laser dc bias 0.1 m f 3 k w 0.1 m f 2 k w v ss voltage divider 0.1 m f 1 w v ss to node v ss2 and v ss3 one each to user voltage monitor (dvm) current sense 0.1 m f v ss to v ss1 bypass for v ss1 required to set v mod and v pre to achieve desired modulation and prebias v th v in (optional) 2 k w v ss = C5.2 v mod_e bg2p5 lm4040 rf input 2000 pwp pwn clk (optional) in in
data sheet february 1999 LG1627BXC clocked laser driver 7 lucent technologies inc. typical optical evaluations and performance characteristics (continued) horizontal: 60 ps/div, vertical: 1.5 mw/div figure 5. typical optical eye-diagram i out = 85 ma; i out-pre = 5 ma 5-7676(f) figure 6. typical i out vs. v mod 5-7677(f)r.1 figure 7. typical i out-pre vs. v pre 0 10 20 30 40 50 60 70 80 90 100 i out (ma) C5.5 C4.5 C5.0 C4.0 v mod ( v ) 0 10 20 30 40 50 60 70 80 i out-pre (ma) C5.5 C4.5 C5.0 C4.0 v pre ( v ) C3.5
data sheet LG1627BXC clocked laser driver february 1999 8 lucent technologies inc. outline diagram 5-6555(f).a assembl y notes: standoff specifications appl y to packa g e prior to solder dippin g of leads and packa g e base. durin g board assembl y , use back li g htin g to silhouette the packa g e. this will eliminate reflection problems with the solder on the bottom of the packa g e. lead space tolerance should be set to 0.012. board solder pattern for the packa g e base should not exceed 50% of the packa g e base area. insertion pressure should not exceed 125 g rams. ordering information device code package temperature comcode (ordering number) LG1627BXC 24-pin hermetic small outline 0 c to 70 c 108325754 1 1 0 0.004 0.082 0.005 0.092 0.045 0.035 0.030 0.012 0.280 0.465
data sheet february 1999 LG1627BXC clocked laser driver 9 lucent technologies inc. notes
data sheet LG1627BXC clocked laser driver february 1999 lucent technologies inc. reserves the right to make changes to the product(s) or information contained herein without notice. n o liability is assumed as a result of their use or application. no rights under any patent accompany the sale of any such product(s) or information. copyright ? 1999 lucent technologies inc. all rights reserved februar y 1999 ds99-143hspl for additional information, contact y our microelectronics group account mana g er or the followin g : internet: http://www.lucent.com/micro e-mail: docmaster@micro.lucent.com n. america: microelectronics group, lucent technolo g ies inc., 555 union boulevard, room 30l-15p-ba, allentown, pa 18103 1-800-372-2447 , fax 610-712-4106 ( in canada: 1-800-553-2448 , fax 610-712-4106 ) asia pacific: microelectronics group, lucent technolo g ies sin g apore pte. ltd., 77 science park drive, #03-18 cintech iii, sin g apore 118256 tel. (65) 778 8833 , fax ( 65 ) 777 7495 china: microelectronics group, lucent technolo g ies ( china ) co., ltd., a-f2, 23/f, zao fon g universe buildin g , 1800 zhon g shan xi road, shan g hai 200233 p. r. china tel. (86) 21 6440 0468 , ext. 316 , fax ( 86 ) 21 6440 0652 japan: microelectronics group, lucent technolo g ies japan ltd., 7-18, hi g ashi-gotanda 2-chome, shina g awa-ku, tok y o 141, japan tel. (81) 3 5421 1600 , fax ( 81 ) 3 5421 1700 europe: data re q uests: microelectronics group dataline: tel. (44) 1189 324 299 , fax ( 44 ) 1189 328 148 technical in q uiries: germany: (49) 89 95086 0 ( munich ) , united kingdom: (44) 1344 865 900 ( ascot ) , france: (33) 1 40 83 68 00 ( paris ) , sweden: (46) 8 594 607 00 ( stockholm ) , finland: (358) 9 4354 2800 ( helsinki ) , italy: (39) 02 6608131 ( milan ) , spain: (34) 1 807 1441 ( madrid )
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