VITESSE
SEMICONDUCTOR CORPORATION
Preliminary Data Sheet
VSC7927
Features
• Rise Times of Less Than 100ps • High Speed Operation (Up to 2.5 Gb/s NRZ Data) • Differential or Single-Ended Inputs • Single Supply • ECL-Compatible Clock and Data Inputs
SONET/SDH 2.5Gb/s Laser Diode Driver
• Direct Access to Modulation and Bias FETs • Data Density Monitors • On-Chip Reclocking Register • On-Chip Mux for Clocked or Non-clocked Applications • On-Chip 50Ω Input Termination: Clock and Data
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 NMK
IOUT NIOUT
DIN 50 Ω** DINTERM* 50 Ω** NDIN
DQ
M U X
IBIAS
DCC CLK 50 Ω** CLKTERM* 50 Ω ** NCLK SEL MIP *Terminated to Off-chip Capacitor **On Die Components VIB VIP
IMOD
IBIAS
MIB
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: prodinfo@vitesse.com Internet: www.vitesse.com
Page 1
VITESSE
SEMICONDUCTOR CORPORATION
Preliminary Data Sheet
SONET/SDH 2.5Gb/s Laser Diode Driver
Table 1: Signal Pin Reference Signal
DIN, NDIN MK, NMK NIOUT IOUT VSS GND VIP MIP VIB MIB IBIAS CLK, NCLK DINTERM CLKTERM DCC SEL Total Pins
VSC7927
Description
Data Input and Data Reference, On-chip 50Ω Termination Data Density Differential Outputs Laser Modulation Current Output (Complementary) Laser Modulation Current Output (to Laser Cathode) Negative Voltage Rail Positive Voltage Rail Modulation Gate Node Modulation Source Node Bias Gate Node Bias Source Node Laser Bias Output (To Laser Cathode) Clock Input and Clock Reference, On-chip 50Ω Termination Data Reference Clock Reference Duty Cycle Control, Leave Floating Clk/Non-clk Data Select
Type
In Out Out Out Pwr Pwr In In In In Out In In In In In
Level
ECL ECL
# Pins
2 2 1 1 2 5 1 1 1 1 1 2 1 1 1 1 24
— —
Pwr Pwr DC DC DC DC DC ECL DC DC DC DC
—
—
Table 2: Mux Select Logic Table SEL
VSS GND N/C
Mode Select
Clocked Data In Non-clocked Data In Non-clocked Data In
Table 3: Absolute Maximum Ratings Symbol
VSS TJ TSTG
Rating
Negative Power Supply Voltage Maximum Junction Temperature Storage Temperature
Limit
VCC to -6.0V -55°C to + 125°C -65°C to +150°C
Table 4: Recommended Operating Conditions Symbol
GND VSS TCl TJ
Parameter
Positive Voltage Rail Negative Voltage Rail Operational Temperature Junction Temperature
(1)
Min —
-5.5 -40
Typ
0 -5.2
Max —
-4.9 85
(2)
Units
V V °C °C
Conditions
—
— —
Power dissipation = 1.3W
125
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: prodinfo@vitesse.com Internet: www.vitesse.com G52201-0, Rev 3.0 04/05/01/01
VITESSE
SEMICONDUCTOR CORPORATION
Preliminary Data Sheet
VSC7927
Table 5: High Speed Inputs and ECL Outputs Symbol
VIN VCM VOH VOL VIN
SONET/SDH 2.5Gb/s Laser Diode Driver
Parameter
Single-ended Input Voltage Swing Differential Input Common Mode Range ECL Output High Voltage ECL Output Low Voltage On-Chip Terminations
Min
300 -2.3 -1200
Typ — — — — —
Max
1500 -1.3
Units
mVp-p V mV mV Ω
Conditions
VCM = -2.0V VSS = -5.2V 50Ω to -2.0V 50Ω to -2.0V
—
-1600 65
—
35
Table 6: Power Dissipation Symbol
IVSS PD
Parameter
Power Supply Current (VSS) Total Power Dissipation
Min — —
Typ — —
Max
120 700
Units
mA mW
Conditions
VSS = -5.5V, IMOD = IBIAS = 0mA, MK/NMK open circuit VSS = -5.5V, IMOD = IBIAS = 0mA, RLOAD = 25Ω to GND, MK/NMK terminated 50Ω to -2V
Table 7: Laser Driver DC Electrical Specifications Symbol
IBIAS IMOD VIB VIP VOCM
Parameter
Programmable Laser Bias Current Programmable Modulation Current Laser Bias Control Voltage Laser Modulation Control Voltage Output Voltage Compliance
Min
2 2 — —
Typ
— — — — GND 3V
Max
100 100 VSS + 2.1 VSS + 2.1 —
Units
mA mA V V V —
Conditions —
IBIAS = 50mA IMOD= 60mA VSS = -5.2V
—
Table 8: Laser Driver AC Electrical Specifications Symbol
tR, tF tSU tH
Parameter
Output Rise and Fall Times Data to Clock Setup Time Hold Time
Min — — 20
Typ —
50 50
Max
100
Units
ps ps ps
Conditions
25Ω load, 20%-80%, 20mA < IMOD < 60mA, IBIAS = 60mA
90 —
— —
Table 9: Package Thermal Specifications Symbol
θJCC
Parameter
Thermal Resistance from Junction-to-Case
Min —
Typ
25
Max —
Units
°C/W
Conditions
Ceramic Package
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: prodinfo@vitesse.com 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 PD PD = = = = = = = -5.2V 40mA 20mA -2.0V -2.0V (-5.2 * 150mA) + ((5.2 - 2.0) * 40mA) + ((5.2-- 2.0) * 20mA) 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 PD PD = = = = = = = -5.5V 60mA 50mA 0V 0V (5.5 * 150mA) + (5.5 * 60mA) + (5.5mA * 50mA) 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: prodinfo@vitesse.com 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 6.4K
X
* 50
X
*On-chip Components
VSS VSS
DINTERM to -2.0V for Differential ECL Inputs
Figure 2: Single-Ended Operation
DATA SOURCE
0.1µf GND
0.1µf
7927
DIN DINTERM NDIN
0.1µf 0.1µf GND
CLOCK SOURCE
0.1µf GND
CLK CLKTERM NCLK
0.1µf GND
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: prodinfo@vitesse.com Internet: www.vitesse.com
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VITESSE
SEMICONDUCTOR CORPORATION
Preliminary Data Sheet
SONET/SDH 2.5Gb/s Laser Diode Driver
Figure 3: Single-Ended AC-Coupled
GND
VSC7927
0.1µf SOURCE
DINTERM (CLKTERM)
DIN (CLK)
X
50 4.0K -2.0V 50 6.4K
X X
0.1µf GND
NDIN (NCLK)
0.1µf
VSS
GND
Figure 4: Differential AC-Coupled
GND
0.1µf SOURCE 0.1µf
DIN (CLK)
X
DINTERM (CLKTERM)
50
4.0K -2.0V
X
0.1µf GND
NDIN (NCLK)
50
6.4K
X
VSS
Figure 5: Differential DC-Coupled
GND
DIN (CLK)
X
SOURCE
DINTERM (CLKTERM)
50
4.0K -2.0V
X
NDIN (NCLK)
50
6.4K
X
-2.0V
VSS
Page 6
© VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: prodinfo@vitesse.com Internet: www.vitesse.com
G52201-0, Rev 3.0 04/05/01/01
VITESSE
SEMICONDUCTOR CORPORATION
Preliminary Data Sheet
VSC7927
I (MIB) 30 mA
SONET/SDH 2.5Gb/s Laser Diode Driver
Figure 6: Control Signals VIP and VIB
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
IOUT
IBIAS
X
X
X
VIP
X
IMOD
OUTPUT DIFF PAIR IBIAS
X VIB
X
MIP
X
MIB
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: prodinfo@vitesse.com Internet: www.vitesse.com
Page 7
VITESSE
SEMICONDUCTOR CORPORATION
Preliminary Data Sheet
SONET/SDH 2.5Gb/s Laser Diode Driver
Figure 8: Pad Assignments for VSC7927 Die
1720µm 1620µm 50µm 50µm
VSC7927
50µm
120 120µm 150µm
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 2 NDIN PAD 3 DIN PAD 4 DINT PAD 5 CLOCKT PAD 6 CLOCK PAD 7 NCLOCK PAD 8 N/C SEL PAD 9 GND PAD 10 PAD 25 VIB PAD 24 GND PAD 23 IOUT PAD 22 IOUT PAD 21 GND PAD 20 GND PAD 19 NIOUT PAD 18 IBIAS GND GND GND GND GND NMARK MARK PAD 11 PAD 12 PAD 13 PAD 14 PAD 15 PAD 16 PAD 17
30µm
1620µm
1720µm
50µm
Die Size: Actual Die Size: Pad Size: Pad Pitch: Space Between Pads:
1620µm x 1620µm 1720µmx1720µm (after the die are cut up) 120µm x 120µm 150µm 30µm
Page 8
© VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: prodinfo@vitesse.com 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
Pin Diagram for 24-Pin Ceramic Package
DCC MIB
19 18 17 16 15 14 7 8 9 10 11 13 12
VSS
VSS
NDIN DIN DINTERM CLKTERM CLK NCLK
24 1 2 3 4 5 6
23
22
21
20
MIP
VIP
VIB GND IOUT GND NIOUT IBIAS
SEL
GND
GND
GND
MK
Note:
Package lid and bottom heat spreader are electrically connected to GND within the package.
MK
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: prodinfo@vitesse.com Internet: www.vitesse.com
Page 9
VITESSE
SEMICONDUCTOR CORPORATION
Preliminary Data Sheet
SONET/SDH 2.5Gb/s Laser Diode Driver
VSC7927
Package Information - 24 Pin Ceramic Package (Formed Leads)
Top View
A 24 23 22 21 20 19
Key
A B C D
mm
9.5 7.7 2.0 1.27 0.30 1.7 0.6 11.5 0.125 8.51
In
0.374 0.303 0.079 0.050 0.012 0.067 0.024 0.453 0.005 0.335
INDEX E 1 2 3 A 4 5 6 15 14 13 17 16 18
E F G H I J
7
8
9
10 11
D 12
Side View
B
I J H C
G
F
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: prodinfo@vitesse.com 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
Key
A B C D
mm
9.5 7.7 5.8 1.27 0.30 1.7 0.6 9.53 0.125 8.51
In
0.374 0.303 .230 0.050 0.012 0.067 0.024 0.375 0.005 0.335
INDEX E 1 2 3 A 4 5 6 15 14 13 17 16 18
E F G H I J
7
8
9
10 11
D 12
Side View
B
I
G
F
C
H
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: prodinfo@vitesse.com Internet: www.vitesse.com
Page 11
VITESSE
SEMICONDUCTOR CORPORATION
Preliminary Data Sheet
SONET/SDH 2.5Gb/s Laser Diode Driver
VSC7927
Ordering Information
The order number for this product is formed by a combination of the device number, and package style.
VSC7927
Device Type VSC7927: 2.5Gb/s Laser Diode Driver
XX
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: prodinfo@vitesse.com Internet: www.vitesse.com
G52201-0, Rev 3.0 04/05/01/01