Datasheet VSC7990W Datasheet (VITESSE)

VITESSE

SEMICONDUCTOR CORPORATION

Advance Product Information

VSC7990

SONET/SDH 10.7Gb/s

Laser Diode Driver

G52303-0, Rev 2.2 Page 1
04/05/01

© VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012

Tel: (800) VITESSE • FAX: [phone] • Email: [e-mail]

Internet: www.vitesse.com

Features

General Description

The VSC7990 is a single +5V or −5.2V supply, 10.7Gb/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. Clock and data inputs are differentially terminated to 50

Ω and

must be AC-coupled. The superl at ive edge- rat e and dr iv e cur re nt of t he VSC7990 enables efficient design of an
OC-192/STM-64 transmitter using di rect ly modul at ed lase r diod es. A two- chi p OC-12 to OC-1 92 opti cal trans­mitter can be easily implemented using the VSC7990 and the VSC8171 10Gb/s MUX/CRU.

Applications

• OC-192/STM-64 @ 2.488Gb/s to 10.7Gb/s

• 10Gb/s Serial Ethernet

VSC7990 Block Diagram

• 100mA Available Modulation Current

• 100mA Available Bias Current

• 10.7Gb/s Operation

• Duty Cycle Control

• Single Power Supply

• Direct Access to Modulation and Bias FETs

• On-chip Reclocking Register

• On-chip MUX for Selectable Clocked or Unclocked
Applications

• On-chip 50

Ω Input Termination for Clock and Data

• Av ailab le in Tested Bare Die

50Ω

(2)

D

MUX

Q

DIN

PWN
PWP

VTHD

(1)

50Ω

(2)

NDIN

VTHDN

(1)

50Ω

(2)

(2)

CLK

NCLK

I

MOD

VIB

3Ω

VIP

CLKSEL

MIP

I

BIAS

MIB

IOUT
NIOUT
IBIAS

NOTES: (1) Terminated to off-chip capacitor. (2) On-die components.

3Ω

50Ω

(2)

(2)

VITESSE

SEMICONDUCTOR CORPORATION

Advance Product Inf ormation

VSC7990

SONET/SDH 10.7Gb/s
Laser Diode Driver

Page 2 G52303-0, Rev 2.2

04/05/01

© VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012

Tel: (800) VITESSE • FAX: [phone] • Email: [e-mail]

Internet: www.vitesse.com

AC Characteristics (Over recommended operating conditions)

Table 1: High-Speed Inputs and ECL Outputs

Table 2: Laser Driver AC Electrical Specifications

DC Characteristics (Over recommended operating conditions)

Table 3: Power Dissipat ion

Table 4: Laser Driver DC Electrical Specifications

Symbol Parameter Min Typ Max Units Conditions

V

IN

Single-ended Input Voltage Swing 400 1000 mVp-p V

CM

= −3.7V

V

IN

On-Chip Terminations 35 65 Ω

Symbol Parameter Min Typ Max Units Conditions

tR, t

F

Output Rise and Fall Times 35 ps

RL = 25Ω, 20% to 80%,
20mA < I

MOD

< 100mA

t

SU

Data to Clock Setup Time TBD ps

t

H

Hold Time TBD ps

Symbol Parameter Min Typ Max Units Conditions

I

VSS

Power Supply Current (VSS) 150 mA VSS = −5.5V, I

MOD

= I

BIAS

= 0mA

P

D

Total Power Dissipation 800 mW VSS = −5.5V, I

MOD

= I

BIAS

= 0mA

Symbol Parameter Min Typ Max Units Conditions

I

BIAS

Programmable Laser Bias Current 2  100 mA 

I

MOD

Programmabl e Mo du la tio n Cur re nt 1  100 mA 

V

IB

Laser Bias Contr ol Voltage VSS+2.1V V I

BIAS

= 60mA

V

IP

Laser Modulation Control Voltage VSS+2.1V V I

MOD

= 100mA

V

OCM

Output Voltage Compliance  GND −3V  VV

SS

= −5.2V

VITESSE

SEMICONDUCTOR CORPORATION

Advance Product Information

VSC7990

SONET/SDH 10.7Gb/s

Laser Diode Driver

G52303-0, Rev 2.2 Page 3
04/05/01

© VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012

Tel: (800) VITESSE • FAX: [phone] • Email: [e-mail]

Internet: www.vitesse.com

Table 5: MUX Select Logic Table

Table 6: MOD_EN Logic Table

Absolute Maximum Ratings

(1)

Negative Power Supply Voltage (VSS)...........................................................................................................-6.0V

All Pins............................................... ........ .......................................................................................V

SS

to + 0.5V

Supply Voltage (V

SS

) .....................................................................................................................................-6.0V

Supply Current (I

SS

)....................................................................................................................................300mA

Input Voltage (V

IN

).............................................................................................................................VSS to +0.5V

Modulation Control Voltage (V

IP

)......................................................................................................VSS to +0.5V

Maximum Junction Temperature Range ......................................................................................-55°C to +125°C

Storage Temperature Range .........................................................................................................-65°C to +150°C

NOTE: (1) CAUTION: Stresses listed under “Absolute Maximum Ratings” may be applied to devices one at a time without caus-

ing permanent damage. Functionality at or above the values listed is not implied. Exposure to these values for extended
periods may affect device reliability.

Recommended Operating Conditions

Positive Voltage Rail (GND, VDD)..................................................................................................................... 0V

Negative Voltage Rail (V

SS

).............................................................................................................-5.5V to -4.9V

Junction Temperature Operating Range (T

J

) ...................................................................................0°C to +125°C

SEL

Mode Select

V

SS

Clocked Data In

GND (V

DD

) Unclocked Data In

N/C Unclocked Data In

SEL

Mode Select

V

SS

Modulation Current Enabled

GND (V

DD

) Modulation Current Disabled

VITESSE

SEMICONDUCTOR CORPORATION

Advance Product Inf ormation

VSC7990

SONET/SDH 10.7Gb/s
Laser Diode Driver

Page 4 G52303-0, Rev 2.2

04/05/01

© VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012

Tel: (800) VITESSE • FAX: [phone] • Email: [e-mail]

Internet: www.vitesse.com

Figure 1: Single-Ended AC-Coupled

Data

Source

0.1µF

0.1µF

DIN

50Ω

(1)

50Ω

(1)

7kΩ

(1)

2.6kΩ

(1)

V

SS

VTHD

(1) On-chip components.

V

SS

7kΩ

(1)

2.6kΩ

(1)

V

SS

0.1µF

NDIN

0.1µF

VTHDN

Clock

Source

0.1µF

CLK

50Ω

(1)

50Ω

(1)

7kΩ

(1)

2.6kΩ

(1)

(1)

(1)

V

SS

V

SS

7kΩ

(1)

2.6kΩ

(1)

V

SS

0.1µF

Chip

Boundary

NCLK

VITESSE

SEMICONDUCTOR CORPORATION

Advance Product Information

VSC7990

SONET/SDH 10.7Gb/s

Laser Diode Driver

G52303-0, Rev 2.2 Page 5
04/05/01

© VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012

Tel: (800) VITESSE • FAX: [phone] • Email: [e-mail]

Internet: www.vitesse.com

Figure 2: Differential AC-Coupled

Data

Source

0.1µF

0.1µF

0.1µF

0.1µF

DIN

50Ω

(1)

50Ω

(1)

7kΩ

(1)

2.6kΩ

(1)

V

SS

VTHD

(1) On-chip components.

V

SS

7kΩ

(1)

2.6kΩ

(1)

V

SS

NDIN

0.1µF

VTHDN

Clock

Source

0.1µF

CLK

50Ω

(1)

50Ω

(1)

7kΩ

(1)

2.6kΩ

(1)

(1)

(1)

V

SS

V

SS

7kΩ

(1)

2.6kΩ

(1)

V

SS

Chip

Boundary

NCLK

VITESSE

SEMICONDUCTOR CORPORATION

Advance Product Inf ormation

VSC7990

SONET/SDH 10.7Gb/s
Laser Diode Driver

Page 6 G52303-0, Rev 2.2

04/05/01

© VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012

Tel: (800) VITESSE • FAX: [phone] • Email: [e-mail]

Internet: www.vitesse.com

Figure 3: Control Signals VIP and VIB

Figure 4: Simplified Output Structure

30mA

60mA

I (MIB)

I (MIP)

VIP

VIB

V

SS

+ 1.5V (typical)

V

SS

+ 1.5V (typical)

Typical Bias Current vs. Bias Voltage

Typical Modulation Current vs. Modulation Voltage

I

MOD

v

SS

VIP

MIP

VIB

MIB

I

BIAS

I

BIAS

V

DD

Output

Differential

Pair

NIOUT IOUT

2.5kΩ 2.5kΩ3Ω 3Ω

500Ω

300Ω

v

SS

VITESSE

SEMICONDUCTOR CORPORATION

Advance Product Information

VSC7990

SONET/SDH 10.7Gb/s

Laser Diode Driver

G52303-0, Rev 2.2 Page 7

04/05/01

© VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012

Tel: (800) VITESSE • FAX: [phone] • Email: [e-mail]

Internet: www.vitesse.com

Package Pin Descriptions

Figure 5: Pad Assignments

2159µm (0.085")

1270

µm

(0.050")

VSC7990

0.002"
(51µm)

0.002"
(51µm)

Die Size with Scribe: 2159µm x 1270µm (0.085" x 0.050")
Die Thickness: 381µm (0.015")
Pad Pitch: 127µm (0.005")
Pad to Pad Clearance: 51µm (0.002")
Pad Size: 77µm x 77µm (0.003" x 0.003")
Pad Passivation Opening: 76.2µm x 76.2µm (0.003" x 0.003")
Scribe Size: 50µm (0.002")

Pad 39

IBIAS

Pad 40

IBIAS

Pad 38

VDD

Pad 37

VDD

Pad 36

VDD

Pad 35

VDD

Pad 34NCPad 33

VDD

Pad 32

IOUT

Pad 31

VDD

Pad 30
NIOUT

Pad 29

VDD

Pad 28NCPad 27

VDD

Pad 26

VDD

Pad 25

VDD

Pad 24

VDD

Pad 23

VIP

Pad 22

MIP

Pad 21

VSS

Pad 20

VSS

Pad 19

MOD_EN

Pad 18

PWN

Pad 17

PWP

Pad 2

VDD

Pad 3

DIN

Pad 4

VDD

Pad 5
NDIN

Pad 6

VDD

Pad 7

CLK

Pad 8

VDD

Pad 9
CLKN

Pad 10

VDD

Pad 11

VDD

Pad 12

VDD

Pad 13

VDD

Pad 14

CLKSEL

Pad 15

VDD

Pad 16

NC

Pad 41

NC

Pad 42

VIB

Pad 43

MIB

Pad 44

VSS

Pad 45

VSS

Pad 46
VTHDN

Pad 1
VTHD

VITESSE

SEMICONDUCTOR CORPORATION

Advance Product Inf ormation

VSC7990

SONET/SDH 10.7Gb/s
Laser Diode Driver

Page 8 G52303-0, Rev 2.2

04/05/01

© VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012

Tel: (800) VITESSE • FAX: [phone] • Email: [e-mail]

Internet: www.vitesse.com

Table 7: Pad Locations for VSC7990 Die

Pin # Signal Name Signal Type Levels Description

1VTHD——Input Bias Thresh old Ad jus t, True
2VDD— 0V Ground
3DIN IECL

(1)

Data Input, True
4VDD— 0V Ground
5 NDIN I ECL

(1)

Data Input, Complement
6VDD— 0V Ground
7CLK IECL

(1)

Clock Input, True
8VDD— 0V Ground
9CLKN IECL

(1)

Clock Input, Comp le m en t

10 VDD — 0V Ground
11 VDD — 0V Ground
12 VDD — 0V Ground
13 VDD — 0V Ground
14 CLKSEL I — Clock Select (see Table 5)
15 VDD — 0V Ground
16 NC ——No Connection
17 PWP I — Duty Cycle Control, Positive
18 PWN I — Duty Cycle Control, Negative
19 MOD_EN I ECL Modulation Output Enable
20 VSS —–5.2V Power Supply
21 VSS —–5.2V Power Supply
22 MIP O — Modulation Current Monitor
23 VIP I — Modulation Set Voltage
24 VDD — 0V Ground
25 VDD — 0V Ground
26 VDD — 0V Ground
27 VDD — 0V Ground
28 NC ——No Connection
29 VDD — 0V Ground
30 NIOUT O — Modulation Current Out, Complement
31 VDD — 0V Ground
32 IOUT O — Modulation Curre nt Out, True
33 VDD — 0V Ground
34 NC ——No Connection
35 VDD — 0V Ground
36 VDD — 0V Ground
37 VDD — 0V Ground

VITESSE

SEMICONDUCTOR CORPORATION

Advance Product Information

VSC7990

SONET/SDH 10.7Gb/s

Laser Diode Driver

G52303-0, Rev 2.2 Page 9
04/05/01

© VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012

Tel: (800) VITESSE • FAX: [phone] • Email: [e-mail]

Internet: www.vitesse.com

NOTE: (1) Data and clock input s are ECL-sw ing but not ECL level. Inputs must be AC-coupled as shown in Figures 2 and 3 of

this data sheet.

38 VDD — 0V Ground
39 IBIAS O — Bias Current Output
40 IBIAS O — Bias Current Output
41 NC ——No Connection
42 VIB I — Bias Output Adjust
43 MIB O — Bias Current Monitor
44 VSS —–5.2V Power Supply
45 VSS —–5.2V Power Supply
46 VTHDN ——Input Bias Threshold Adjust for Data, Complement

Pin # Signal Name Signal Type Levels Description

VITESSE

SEMICONDUCTOR CORPORATION

Advance Product Inf ormation

VSC7990

SONET/SDH 10.7Gb/s
Laser Diode Driver

Page 10 G52303-0, Rev 2.2

04/05/01

© VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012

Tel: (800) VITESSE • FAX: [phone] • Email: [e-mail]

Internet: www.vitesse.com

Ordering Informatio n

The order number for this product is formed by a combination of the device type and package style.

VSC7990

XX

Device Type

SONET/SDH 10.7Gb/s Laser Diode Driver

Package Style

W : Bare die in waffle pack

Notice

Vitesse Semiconductor Corporation (“Vitesse”) provides this document for informational purposes only. This document contains pre-production
information about Vitesse products in their conce pt, development and/or testi ng phase. All information in t his document, including de scriptions of
features, functions, performa n ce, technical specif ications and availability, is subject to change without notice at any time. Nothing contained in this
document shall be con stru ed a s e xten ding an y warr an ty or pr omise , ex press or imp lied, that any Vitesse product wil l be avai lab le as described or
will be suitable for or will accompli sh any particular task.

Vitesse products are not intended for use in life support applia nc es, devices or systems. Use of a Vitesse product in such applications without writ­ten consent is prohibited