VITESSE SEMICONDUCTOR CORPORATION Preliminary Data Sheet VSC7925 SONET/SDH 2.5Gb/s Laser Diode Driver Features Applications • Rise Times Less Than 100ps • High Speed Operation (Up to 2.5Gb/s NRZ Data) • SONET/SDH at 622Mb/s, 1.244Gb/s, and 2.488Gb/s • Single-ended Inputs • Full-Speed Fibre Channel (1.062Gb/s) • Single Supply • Direct Access to Modulation and Bias FET’s • Data Density Monitors • On-Chip Reclocking Register • 24-Pin Ceramic Package General Description The VSC7925 is a single 5V supply, 2.5Gb/s laser diode driver with direct access to the laser modulation and bias FETs. Laser bias and modulation currents are set by external components allowing precision monitoring and setting of the current levels. Data density outputs are provided to allow the user to adjust the laser bias in unbalanced data applications. Clock and data inputs have nominal 50Ω termination resistors and high frequency decoupling capacitors.P VSC7925 Block Diagram MK IOUT NMK NIOUT DIN 50Ω ** 10pF ** D DCC Q IBIAS NDIN* DCC IBIAS VIP CLK 50Ω NCLK* 10pF IMOD ** ** VIB MIP MIB * Terminated to off-chip capacitor ** On-die components G52157-0, Rev 3.2 05/01/01 © VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: [email protected] Internet: www.vitesse.com Page 1 VITESSE SEMICONDUCTOR CORPORATION Preliminary Data Sheet VSC7925 SONET/SDH 2.5Gb/s Laser Diode Driver Table 1: Signal Pin Reference Signal Type DIN, NDIN In MK, NMK Out NIOUT Out Level # Pins ECL Description 2 Data Input and Data Reference 2 Data Density Differential Outputs 1 Laser Modulation Current Output (Complementary) IOUT Out 1 Laser Modulation Current Output (To Laser Cathode) VSS Pwr Pwr 4 Negative Voltage Rail GND Pwr Pwr 6 Positive Voltage Rail VIP In DC 1 Modulation Gate Node MIP In DC 1 Modulation Source Node VIB In DC 1 Bias Gate Node MIB IBIAS In DC 1 Bias Source Node Out DC 1 Laser Bias Output (To Laser Cathode) 2 Clock Input and Clock Reference 1 Duty Cycle Control, Leave Floating CLK, NCLK In DCC In DC Total Pins 24 Table 2: Absolute Maximum Ratings Symbol Rating Limit VSS Negative Power Supply Voltage VCC to -6.0V TJ Maximum Junction Temperature -55°C to + 125°C TSTG Storage Temperature -65°C to +150°C Table 3: High-Speed Inputs and ECL Outputs Symbol Parameter Min Typ Max Units Conditions VIN Single-ended Input Voltage Swing 300 1500 mV VCM = -2.5V VCM Differential Input Common Mode Range -3.3 -1.3 V VSS = -5.2V VOH ECL Output High Voltage -1200 -500 mV 50Ω to -2.0V VOL ECL Output Low Voltage -2000 -1600 mV 50Ω to -2.0V Page 2 © VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: [email protected] Internet: www.vitesse.com G52157-0, Rev 3.2 05/01/01 VITESSE SEMICONDUCTOR CORPORATION Preliminary Data Sheet VSC7925 SONET/SDH 2.5Gb/s Laser Diode Driver Table 4: Recommended Operating Conditions Symbol Parameter Min GND Positive Voltage Rail VSS Negative Voltage Rail -5.5 TCASE KF Operational Temperature9.0 pt -40 Typ Max 0 -5.2 Units Conditions V -4.9 V 85 °C Power dissipation = 1.3W Ceramic Package NOTE: (1) Lower limit of specification is ambient temperature and upper limit is case temperature. Table 5: Power Dissipation Symbol Parameter Min Typ Max Units Conditions IVSS Power Supply Current (VSS) 220 mA IMOD = IBIAS = 0mA PD Total Power Dissipation 1200 mW VSS = -5.5V, IMOD = IBIAS = 0mA, RLOAD = 25Ω to GND Max Units Conditions 50 mA 60 mA Table 6: Laser Driver DC Electrical Specifications Symbol Parameter Min Typ IBIAS Programmable Laser Bias Current 2 IMOD Programmable Modulation Current 2 VIB Laser Bias Control Voltage VSS + 2.1 V IBIAS = 50mA VIP Laser Modulation Control Voltage VSS + 2.1 V IMOD= 60mA VOCM Output Voltage Compliance V VSS = -5.2V - GND -2.5V Table 7: Laser Driver AC Electrical Specifications Symbol Parameter Min Typ Max Units 100 ps tR, tF Output Rise and Fall Times tSU Data to Clock Setup Time 50 ps tH Hold Time 50 ps G52157-0, Rev 3.2 05/01/01 Conditions 25Ω load, 20%-80%, 15mA < IMOD < 60mA, IBIAS = 20mA © VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: [email protected] Internet: www.vitesse.com Page 3 VITESSE SEMICONDUCTOR CORPORATION Preliminary Data Sheet VSC7925 SONET/SDH 2.5Gb/s Laser Diode Driver Figure 1: Laser Driver Maximum Case Temperature vs. Modulation Current CASE TEMPERATURE vs. MODULATION CURRENT 90 Case Temperature (oC) 80 70 60 50 40 30 20 10 0 0 10 20 30 40 50 60 Modulation Current (mA) 70 80 Figure 2: Clock and Data Input Structure X 0V (GND) DIN (CLK) X + 2000 2kΩ 50 50Ω NDIN (NCLK) X - VREF 3 •Nominal VREF Value = -2.5V •All Values Nominal 10pF 2000 2kΩ X X 0V (GND) -5.2V(VSS) Figure 3: Single-Ended Operation DATA SOURCE 7925 VSC7925 0.1µf DIN NDIN 0.1µf CLOCK SOURCE 0.1µf GND CLK NCLK 0.1µf GND Page 4 © VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: [email protected] Internet: www.vitesse.com G52157-0, Rev 3.2 05/01/01 VITESSE SEMICONDUCTOR CORPORATION Preliminary Data Sheet VSC7925 SONET/SDH 2.5Gb/s Laser Diode Driver Figure 4: Control Signals VIP and VIB I (MIB) 50 mA VIB 2.1V Typical Bias Current v.s. Bias Voltage I (MIP) 60 mA VIP 2.1V Typical Modulation Current v.s. Modulation Voltage Figure 5: Simplified Output Structure NIOUT X VIP IOUT X OUTPUT DIFF PAIR X IMOD G52157-0, Rev 3.2 05/01/01 IBIAS X X VIB IBIAS X X MIP MIB © VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: [email protected] Internet: www.vitesse.com Page 5 VITESSE SEMICONDUCTOR CORPORATION Preliminary Data Sheet VSC7925 SONET/SDH 2.5Gb/s Laser Diode Driver Figure 6: Pad Assignments for VSC7925 Die 1720 1620 50 120 120 150 30 PAD 34 PAD 33 PAD 32 PAD 31 PAD 30 PAD 29 DCC VSS VSS VSS VSS VIP PAD 28 PAD 27 PAD 26 MIP MIP MIB PAD 1 DINTERM PAD 25 VIB PAD 2 DINTERM PAD 24 GND0 PAD 3 DIN PAD 23 OUT PAD 4 GND PAD 22 OUT PAD 5 GND PAD 21 GND0 PAD 6 CLOCK PAD 20 GND0 PAD 7 CLOCKTERM PAD 19 NOUT PAD 8 CLOCKTERM PAD 18 IBIAS VSS PAD 9 VSS PAD 10 GND PAD 11 50 50 1620 1720 GND GND GND GND NMARK MARK PAD 12 PAD 13 PAD 14 PAD 15 PAD 16 PAD 17 50 Dimensions in micrometers. 1) 2) 3) 4) 5) Page 6 Die size = 1620µm x 1620µm Actual die size = 1720µm x 1720µm (after the die are cut up) Pad size = 120µm x 120µm Pad pitch = 150µm Space between pads = 30µm © VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: [email protected] Internet: www.vitesse.com G52157-0, Rev 3.2 05/01/01 VITESSE SEMICONDUCTOR CORPORATION Preliminary Data Sheet VSC7925 SONET/SDH 2.5Gb/s Laser Diode Driver VSS VSS VIP MIP MIB 24 23 22 21 20 19 18 GND 3 16 IOUT GND 4 15 GND CLK 5 14 NIOUT NCLK 6 IBIAS 7 8 9 10 11 13 12 MK GND MK 17 GND 2 GND DIN GND 1 VSS NDIN Note: G52157-0, Rev 3.2 05/01/01 DCC Pin Diagram - 24-Pin Ceramic Package VIB Package lid and bottom heat spreader are electrically connected to GND within the package. © VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: [email protected] Internet: www.vitesse.com Page 7 VITESSE SEMICONDUCTOR CORPORATION Preliminary Data Sheet VSC7925 SONET/SDH 2.5Gb/s Laser Diode Driver Package Information - 24 Pin Ceramic Package (Formed Leads) Top View A 24 23 22 21 20 19 INDEX E 18 1 2 17 3 16 4 15 5 14 6 13 Key mm In A 9.5 0.374 B 7.7 0.303 C 2.0 0.079 D 1.27 0.050 E 0.30 0.012 F 1.7 0.067 G 0.6 0.024 H 11.5 0.453 I 0.125 0.005 J 8.51 0.335 A 7 8 9 10 D 11 12 Side View B G I F J H C NOTES: Drawing not to scale. Package #: 101-000-0 Issue #:1 Page 8 © VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: [email protected] Internet: www.vitesse.com G52157-0, Rev 3.2 05/01/01 VITESSE SEMICONDUCTOR CORPORATION Preliminary Data Sheet VSC7925 SONET/SDH 2.5Gb/s Laser Diode Driver Package Information - 24 Pin Ceramic Package (Straight Leads) Top View A 24 23 22 21 20 19 INDEX E 18 1 Key mm In A 9.5 0.374 B 7.7 0.303 C 5.8 .230 D 1.27 0.050 E 0.30 0.012 F 1.7 0.067 G 0.6 0.024 H 9.53 0.375 2 17 I 0.125 0.005 3 16 J 8.51 0.335 4 15 5 14 6 13 A 7 8 9 10 D 11 12 Side View B I G C H F C NOTES: Drawing not to scale. Package #: 101-000-0 Issue #:1 G52157-0, Rev 3.2 05/01/01 © VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: [email protected] Internet: www.vitesse.com Page 9 VITESSE SEMICONDUCTOR CORPORATION Preliminary Data Sheet VSC7925 SONET/SDH 2.5Gb/s Laser Diode Driver Ordering Information The order number for this product is formed by a combination of the device number, and package style. VSC7925 XX Device Type VSC7925: 2.5Gb/s Laser Diode Driver Package Style KF: (Ceramic - Straight Leads) KFL: (Ceramic- Formed Leads) Notice Vitesse Semiconductor Corporation (“Vitesse”) provides this document for informational purposes only. This document contains pre-production information about Vitesse products in their concept, development and/or testing phase. All information in this document, including descriptions of features, functions, performance, technical specifications and availability, is subject to change without notice at any time. Nothing contained in this document shall be construed as extending any warranty or promise, express or implied, that any Vitesse product will be available as described or will be suitable for or will accomplish any particular task. Vitesse products are not intended for use in life support appliances, devices or systems. Use of a Vitesse product in such applications without written consent is prohibited. Page 10 © VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: [email protected] Internet: www.vitesse.com G52157-0, Rev 3.2 05/01/01