NB4N855SMEVB
http://onsemi.com
2
Figure 2. Evaluation Board Lay
−
up
Connecting Power and Ground Planes
The side launch 9 pin power supply connector is wired as
shown in Figure 3. Test points can be soldered on the top of
the PCB to accommodated easier connections. Exact values
that need to be applied can be found in Table 1.
Table 1. Power Supply Levels
Power Supply Span
V
CC
(Pin 10)
V
EE
/ GND
(Pin 5)
DUT_GND
(PCB SMA Ground))
3.0 V
1.75 V
−
1.25 V
0 V
3.3 V
2.05 V
−
1.25 V
0 V
3.6 V
2.35 V
−
1.25 V
0 V
V
CC
DUT_GND
V
EE
/GND
Figure 3. Power Supply Connector
−
9 Pin Side
View (Left) and PCB Top View (Right)
NC
NC
V
CC
V
CC
V
EE
/GND
DUT_GND
Stimulus (Generator) Termination
All ECL outputs need to be terminated to V
TT
(V
TT
= V
CC
–2.0 V = GND) via a 50
W
resistor. The current board design
utilizes the space for placement of the external termination
resistors. (More information on termination is provided in
AN8020). The 0402 chip resistor pads are provided on the
bottom side of the evaluation board. Solder the chip resistors
to the bottom side of the board between the appropriate input
of the device pin pads and the ground pads as shown in
Figure 4 (for split power supply setup, PCB is assembled in
this configuration).
