VSC7925 Datasheet, PDF (1/10 Pages) Vitesse Semiconductor Corporation – SONET/SDH 2.5Gb/s Laser Diode Driver

VITESSE
SEMICONDUCTOR CORPORATION
Preliminary Data Sheet
VSC7925
SONET/SDH 2.5Gb/s Laser Diode Driver
Features
• Rise Times Less Than 100ps
• High Speed Operation (Up to 2.5Gb/s NRZ Data)
• Single-ended Inputs
• Single Supply
• Direct Access to Modulation and Bias FET’s
• Data Density Monitors
• On-Chip Reclocking Register
• 24-Pin Ceramic Package
Applications
• SONET/SDH at 622Mb/s, 1.244Gb/s, and
2.488Gb/s
• Full-Speed Fibre Channel (1.062Gb/s)
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 monitor-
ing 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 fre-
quency decoupling capacitors.P
VSC7925 Block Diagram
DIN
50Ω **
NDIN*
10pF **
DQ
CLK
50Ω **
NCLK*
10pF **
* Terminated to off-chip capacitor
** On-die components
MK
NMK
DCC
DCC
VIP
VIB
IOUT
NIOUT
IBIAS
I_MOD
I_BIAS
MIP
MIB
G52157-0, Rev 3.2
05/01/01
© VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012
Tel: (800) VITESSE • FAX: [phone] • Email: [e-mail]
Internet: www.vitesse.com
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