GD90360 Intel, GD90360 Datasheet - Page 2

• Manufacturer Part Number: GD90360
• Manufacturer: Intel

Specifications of GD90360

• Lead Free Status / Rohs Status: Not Compliant

Functional Details
The GD16360 offers two identical independent channels, each
of which is fully equipped in the GD90360 evaluation board. In-
dividual amplitude adjustments are available, and digital super-
vision functions easily accessible via test pins on the board.
The descriptions below cover both channels with references in
the form Channel1 (Channel2).
Data Inputs
The digital transmit data inputs J1/J2 (J4/J5) are differential
LVPECL inputs, typically 140 - 155 Mbit/s CMI encoded data
from a CMI encoder. A 280 - 311 Mbit/s NRZ coded signal with
short CID runs can alternatively be used. The inputs are 50
transmission lines, AC coupled to the GD16360 and terminated
in R12/R14 (R10/R13). Single ended operation is possible if a
50
The analogue receive data inputs J3 (J6) are single ended 75
inputs. These inputs are mounted as AC coupled signals, ac-
cessing the GD16360 via a high-speed pulse transformer. If
transformer-less connection is preferred, remove the trans-
former and mount a short between pad 1 and 6. Two SMD re-
sistors size 0805 0
The analogue inputs are overvoltage protected by the diodes
D2 (D1) and drop resistors R2 (R1). The 75
input line is R7 (R5), which is located closest possible to the in-
put pins of the GD16360 in order to avoid stub effects and re-
flections from the PCB traces.
Data Outputs
The analogue data outputs from the line drivers are differential
CML outputs. Each channel has two cable drivers. One is cou-
pled out of the board via transformer, the other is AC coupled
with protection diodes. The transformer outputs are differential
outputs from the GD16360, mounted with the transformer in
one branch and a compensating load in the other. The output
line is DC terminated in R39 (R40) = 75 . The signal is AC
coupled to the transformer, and connected single ended out of
the transformer to J13 (J14) to the transmission cable/test
equipment. The coupling capacitor C21 (C22) to the transformer
is balanced by C17 (C18) in the unused branch of the output
stage, and resistor R35 (R37) compensates the impedance of
the expected external load.
The transformerless output similarly consists of a differential
output stage with an AC coupled branch and a branch with a
compensation network R22, C9, R31 (R26, C10, R32) . The sig-
nal is connected via C15 (C16) to connector J7 (J10). A protec-
tion circuit is inserted into this output. It is composed of diode
D3 (D4) and drop-resistor R36 (R38). These drop resistors may
be optimised or omitted (short circuited) for optimum perfor-
mance of the board. The requirements for a protection circuit
depends on the overall system design philosophy and may be
realised in other ways than suggested on the GD90360 board.
The protection circuit is not necessary for the operation of the
GD16360 device.
Individual potentiometers are mounted for regulation of the indi-
vidual outputs. TX01 (TX02) controls the transformer output,
while TXOM1 (TXOM2) controls the transformerless output.
The digital outputs from the cable equaliser is a differential
LVPECL interface, which connects the received CMI signal out
Data Sheet Rev. 02
termination is applied to the unused input.
in series will do the job.
termination of the
GD90360
via J8/J9 (J11/J12). This output is AC coupled out of the board
for easy testing.
The coupling capacitors C13/C11 (C14/C12) can be
short-circuited and R17/24 (R20/R28) removed, if DC coupled
output is preferred.
Mode Control
The GD16360 has loop-back and receiver shut-down for each
of the two channels. The operating modes are controlled by the
DIP switch S1-1/2 (S1-3/4).
Power Supply
The GD90360 evaluation board may be powered from an un-
regulated power supply, delivering 7.5 V, 0.5 A minimum. Stabi-
lised 3.3 V and 5 V supplies for the GD16360 are generated
locally on the board.
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