VITESSE SEMICONDUCTOR CORPORATION Preliminary Data Sheet VSC7927 SONET/SDH 2.5Gb/s Laser Diode Driver Features • Rise Times of Less Than 100ps • Direct Access to Modulation and Bias FETs • High Speed Operation (Up to 2.5 Gb/s NRZ Data) • Data Density Monitors • Differential or Single-Ended Inputs • Single Supply • On-Chip Mux for Clocked or Non-clocked Applications • ECL-Compatible Clock and Data Inputs • On-Chip 50Ω Input Termination: Clock and Data • On-Chip Reclocking Register General Description The VSC7927 is a single 5V supply, 2.5 Gb/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 high unbalanced data applications. Clock and data inputs are differentially terminated to 50Ω. Applications • SDH/SONET @ 622Mb/s, 1.244Gb/s, 2.488Gb/s • Full Speed Fibre Channel (1.062Gb/s) VSC7927 Block Diagram MK IOUT NMK NIOUT DIN D Q 50 Ω** M U X IBIAS DINTERM* 50 Ω** NDIN IMOD DCC IBIAS VIP CLK 50 Ω** CLKTERM* 50 Ω ** VIB NCLK SEL MIP MIB *Terminated to Off-chip Capacitor **On Die Components G52201-0, Rev 3.0 04/05/01 © 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 VSC7927 SONET/SDH 2.5Gb/s Laser Diode Driver Table 1: Signal Pin Reference Signal Type Level # Pins Description DIN, NDIN In ECL 2 Data Input and Data Reference, On-chip 50Ω Termination MK, NMK Out ECL 2 Data Density Differential Outputs NIOUT Out 1 Laser Modulation Current Output (Complementary) IOUT Out — — 1 Laser Modulation Current Output (to Laser Cathode) VSS Pwr Pwr 2 Negative Voltage Rail GND Pwr Pwr 5 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 In DC 1 Bias Source Node Out DC 1 Laser Bias Output (To Laser Cathode) CLK, NCLK In ECL 2 Clock Input and Clock Reference, On-chip 50Ω Termination DINTERM In DC 1 Data Reference CLKTERM In DC 1 Clock Reference DCC In DC 1 Duty Cycle Control, Leave Floating SEL In DC 1 Clk/Non-clk Data Select Total Pins — — 24 IBIAS Table 2: Mux Select Logic Table SEL Mode Select VSS GND Clocked Data In Non-clocked Data In N/C Non-clocked Data In Table 3: 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 4: Recommended Operating Conditions Symbol Parameter Min Typ Max Units GND Positive Voltage Rail — 0 — V VSS Negative Voltage Rail -5.5 -5.2 -4.9 V — — (2) 85 °C 125 °C (1) TCl Operational Temperature -40 TJ Junction Temperature — Conditions Power dissipation = 1.3W NOTES: (1) Lower limit of specification is ambient temperature and upper limit is case temperature. (2) See section “Calculation of the Maximum Case Temperature” for detailed maximum temperature calculations. 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 G52201-0, Rev 3.0 04/05/01/01 VITESSE SEMICONDUCTOR CORPORATION Preliminary Data Sheet VSC7927 SONET/SDH 2.5Gb/s Laser Diode Driver Table 5: High Speed Inputs and ECL Outputs Symbol Parameter Min Typ Max Units 300 — — — — — 1500 mVp-p VIN Single-ended Input Voltage Swing VCM Differential Input Common Mode Range VOH ECL Output High Voltage -1200 VOL ECL Output Low Voltage — VIN On-Chip Terminations 35 -2.3 Conditions VCM = -2.0V -1.3 V VSS = -5.2V — mV 50Ω to -2.0V -1600 mV 50Ω to -2.0V 65 Ω Table 6: Power Dissipation Symbol Parameter Min Typ Max Units Conditions IVSS Power Supply Current (VSS) — — 120 mA VSS = -5.5V, IMOD = IBIAS = 0mA, MK/NMK open circuit PD Total Power Dissipation — — 700 mW VSS = -5.5V, IMOD = IBIAS = 0mA, RLOAD = 25Ω to GND, MK/NMK terminated 50Ω to -2V Min Typ Max Units Conditions 100 mA — — Table 7: Laser Driver DC Electrical Specifications Symbol Parameter IBIAS Programmable Laser Bias Current 2 — IMOD Programmable Modulation Current 2 — 100 mA V IBIAS = 50mA VIB Laser Bias Control Voltage — — VSS + 2.1 VIP Laser Modulation Control Voltage — — VSS + 2.1 V IMOD= 60mA VOCM Output Voltage Compliance — GND 3V — V VSS = -5.2V Min Typ Max Units Table 8: Laser Driver AC Electrical Specifications Symbol Parameter Conditions tR, tF Output Rise and Fall Times — — 100 ps 25Ω load, 20%-80%, 20mA < IMOD < 60mA, IBIAS = 60mA tSU Data to Clock Setup Time — 50 90 ps — tH Hold Time 20 50 — ps — Table 9: Package Thermal Specifications Symbol θJCC G52201-0, Rev 3.0 04/05/01 Parameter Min Typ Max Units Conditions Thermal Resistance from Junction-to-Case — 25 — °C/W Ceramic 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 3 VITESSE SEMICONDUCTOR CORPORATION Preliminary Data Sheet SONET/SDH 2.5Gb/s Laser Diode Driver VSC7927 Calculation of the Maximum Case Temperature The VSC7927 is designed to operate with a maximum junction temperature of 125°C. The rise from the case to junction is determined by the power dissipation of the device. The power dissipation is determined by the VSS current plus the operating IMOD and IBIAS currents. The power of the chip is determined by the following formula: PD = (-VSS * ISS) + ((VIOUT – VSS) * IMOD) + ((VIBIAS – VSS) * IBIAS) For example with: VSS IMOD IBIAS VIBIAS VIOUT = = = = = -5.2V 40mA 20mA -2.0V -2.0V PD = (-5.2 * 150mA) + ((5.2 - 2.0) * 40mA) + ((5.2-- 2.0) * 20mA) PD = 780mW + 128mW + 64mW = 972mW The thermal rise from junction-to-case is θJC * PD. For the ceramic package, θJCP = 25°C/W. Thus the thermal rise is: 25°C/W * 972W = 24.3°C The maximum case temperature is: 125°C – 24.3°C = 100.7°C The absolute maximum power dissipation of the device is at: VSS IMOD IBIAS VIBIAS VIOUT = = = = = -5.5V 60mA 50mA 0V 0V PD = (5.5 * 150mA) + (5.5 * 60mA) + (5.5mA * 50mA) PD = 1.43W This will net a maximum junction to case thermal rise of: 1.43W * 25°C/W = 35.8°C This situation will allow maximum case temperature of: 35.8°C – 58°C = 89.2°C 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 G52201-0, Rev 3.0 04/05/01/01 VITESSE SEMICONDUCTOR CORPORATION Preliminary Data Sheet VSC7927 SONET/SDH 2.5Gb/s Laser Diode Driver Figure 1: On-chip Data and Clock Input Configuration GND DIN (CLK) DINTERM (CLKTERM) NDIN (NCLK) GND DATA BUFFER (CLOCK BUFFER) X 50 * 4.0K * 50 * 6.4K * X X *On-chip Components VSS VSS DINTERM to -2.0V for Differential ECL Inputs Figure 2: Single-Ended Operation 7927 0.1µf DATA SOURCE DIN DINTERM NDIN 0.1µf 0.1µf GND CLOCK SOURCE GND CLK CLKTERM NCLK 0.1µf 0.1µf GND G52201-0, Rev 3.0 04/05/01 0.1µf GND © 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 VSC7927 SONET/SDH 2.5Gb/s Laser Diode Driver Figure 3: Single-Ended AC-Coupled GND DIN (CLK) 0.1µf X SOURCE DINTERM (CLKTERM) 0.1µf NDIN (NCLK) 50 4.0K 50 6.4K X -2.0V X 0.1µf GND VSS GND Figure 4: Differential AC-Coupled GND 0.1µf DIN (CLK) X SOURCE 0.1µf DINTERM (CLKTERM) 50 -2.0V X NDIN (NCLK) 0.1µf 4.0K 50 6.4K X GND VSS Figure 5: Differential DC-Coupled GND DIN (CLK) X SOURCE DINTERM (CLKTERM) 50 -2.0V X NDIN (NCLK) 4.0K 50 6.4K X -2.0V Page 6 VSS © VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: [email protected] Internet: www.vitesse.com G52201-0, Rev 3.0 04/05/01/01 VITESSE SEMICONDUCTOR CORPORATION Preliminary Data Sheet VSC7927 SONET/SDH 2.5Gb/s Laser Diode Driver Figure 6: Control Signals VIP and VIB I (MIB) 30 mA VIB VSS + 1.5 Volts (Typical) Typical Bias Current v.s. Bias Voltage I (MIP) 60 mA VIP VSS + 1.5 Volts (Typical) Typical Modulation Current v.s. Modulation Voltage Figure 7: Simplified Output Structure NIOUT X VIP IOUT X X OUTPUT DIFF PAIR X IMOD G52201-0, Rev 3.0 04/05/01 IBIAS 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 7 VITESSE SEMICONDUCTOR CORPORATION Preliminary Data Sheet VSC7927 SONET/SDH 2.5Gb/s Laser Diode Driver Figure 8: Pad Assignments for VSC7927 Die 1720µm 50µm 120 120µm 150µm 30µm PAD 34 PAD 33 PAD 32 PAD 31 PAD 30 PAD 29 PAD 28 PAD 27 PAD 26 DCC VSS VSS VSS VSS VIP MIP MIP MIB PAD 1 N/C PAD 25 VIB PAD 2 NDIN PAD 24 GND PAD 3 DIN PAD 23 IOUT PAD 4 DINT PAD 22 IOUT PAD 5 CLOCKT PAD 21 GND PAD 6 CLOCK PAD 20 GND PAD 7 NCLOCK PAD 19 NIOUT PAD 8 N/C PAD 18 IBIAS SEL PAD 9 GND PAD 10 1620µm 1720µm GND GND GND GND GND NMARK MARK PAD 11 PAD 12 PAD 13 PAD 14 PAD 15 PAD 16 PAD 17 1620µm x 1620µm 1720µmx1720µm (after the die are cut up) 120µm x 120µm 150µm 50µm Die Size: Actual Die Size: Pad Size: Pad Pitch: Space Between Pads: Page 8 50µm 1620µm 50µm 30µm © VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: [email protected] Internet: www.vitesse.com G52201-0, Rev 3.0 04/05/01/01 VITESSE SEMICONDUCTOR CORPORATION Preliminary Data Sheet VSC7927 SONET/SDH 2.5Gb/s Laser Diode Driver DCC VSS VSS VIP MIP MIB Pin Diagram for 24-Pin Ceramic Package 24 23 22 21 20 19 18 DINTERM 3 16 IOUT CLKTERM 4 15 GND CLK 5 14 NIOUT NCLK 6 IBIAS Note: G52201-0, Rev 3.0 04/05/01 7 8 9 10 11 13 12 MK GND MK 17 GND 2 GND DIN GND 1 SEL NDIN 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 9 VITESSE SEMICONDUCTOR CORPORATION Preliminary Data Sheet VSC7927 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 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 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 G I F J H C NOTES: Drawing not to scale. Package #: 101-000-0 Issue #:1 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 G52201-0, Rev 3.0 04/05/01/01 VITESSE SEMICONDUCTOR CORPORATION Preliminary Data Sheet VSC7927 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. G52201-0, Rev 3.0 04/05/01 © VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: [email protected] Internet: www.vitesse.com Page 11 VITESSE SEMICONDUCTOR CORPORATION Preliminary Data Sheet VSC7927 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. VSC7927 XX Device Type VSC7927: 2.5Gb/s Laser Diode Driver Package Style KF: (Ceramic - Straight Leads) KFL: (Ceramic- Formed Leads) KFRL: (Ceramic - Reversed Formed Leads}* X : (Bare Die) *Optional Reversed Formed Leads: Package leads have the same profile and dimensions, but heat spreader is away from board. Please contact the factory for additional information. 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 12 © VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: [email protected] Internet: www.vitesse.com G52201-0, Rev 3.0 04/05/01/01