an Intel company
2.5 Gbit/s
Retiming
Laser Driver
GD16571
Preliminary
General Description
The GD16571 is a high performance low
power 2.5 Gbit/s Laser Driver with
optional on chip retiming of data.
The GD16571 is designed to meet and
exceed ITU-T STM-16 or SONET OC-48
fiberoptic communication systems re-
quirements.
The GD16571 is designed to sink a
Modulation Current into the IOUT pin and
a Pre-Bias Current into the IPRE pin. The
Modulation Current is adjustable up to
70 mA by means of the pin VMOD. The
Pre-Bias Current may be adjusted up to
50 mA by means of the VPRE pin.
Retiming of the data signal connected to
the pins DIN, DINQ is made by means of
a DFF clocked by an external clock sig-
nal at the data rate fed to the pins CKIN
and CKINQ.
A Mark-Space monitor is available on the
pins MARKP and MARKN. Together with
the symmetry adjustment pin (SYM) this
may be used to control the mark space
ratio of the output signal.
The GD16571 is implemented in a Sili-
con Bipolar process and requires a single
+5 V supply or a single -5.2 V supply.
The circuit is available in a thermally
enhanced 32-pin TQFP plastic package.
Features
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Complies with ITU-T STM-16 and
SONET OC-48 standards.
Intended for driving a 25
W
load,
e.g. a laser diode with 25
W
input
impedance.
Clocked or non-clocked operation.
Large modulation current adjustment
range from 5 mA to 70 mA.
Output voltage over / under shoot
less than
鹵2
% respectively
鹵
5 %.
Rise / fall times less than 100 ps.
Laser diode pre-bias adjustable up to
50 mA.
Mark-Space monitor.
Symmetry adjustment.
Internal 50
W
termination of data and
clock inputs.
Operates up to 3.5 Gbit/s.
Power dissipation: 0.38 W.
Excluding Modulation Current and
Pre-bias Current.
Silicon Bipolar process.
32 pin thermally enhanced TQFP
plastic package.
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VADJEF
VMOD
VADJBUF
VPRE
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Modulation
Current
Control
CKSEL
DIN
DINQ
50
50
Pre-Bias
Current
Control
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IPRE
Input
Buffer
Output
Driver
VDD
VDDR
VDDCONT
IOUT
IOUTN
VEE
VEEP
VEEB
VEER
MARKP
MARKN
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MUX
D
Q
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DINT
CKIN
CKINQ
50
50
Input
Buffer
Mark/Space
Monitor
SYM
CKINT
Applications
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Tele Communication:
鈥?SDH STM-16
鈥?SONET OC-48
Datacom up to 3.125 Gbit/s.
Electro Absorption laser driver.
Direct Modulation laser driver.
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Data Sheet Rev.: 10
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