
NB4N121K
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7
Figure 9. Typical Termination Configuration for Output Driver and Device Evaluation
CLx for Test Only (Representing Receiver Input Loading); Not Added to Application
CL3D
2 pF
CL4D
2 pF
A. For 1X configuration, connect IREF pin
to GND or for 2X configuration, connect
IREF pin to VCC. To adjust load drive for
1X configuration, use RREF from 0 W to
1 kW, to adjust 2X load, use 20 kW to
50 kW.
B. RL1, RL2: 50 W for 1X Load
25 W for 2X Load
C. RS1, RS2: 0 W for Test and
Evaluation. Select to Minimizing Ringing.
D. CL1, CL2, CL3, CL4: Receiver Input
Simulation Load Capacitance Only
CL1D
2 pF
CL2D
2 pF
Z0 = 50 W
2X Load Option
1X Load
Receiver 2
Receiver
RS1C
RS2C
HCSL
Driver
RREFA
RL1B
50
RL2B
50
Qx
50 W*
VTCLK = VTCLK = VCC 2.0 V
LVPECL
Driver
Z0 = 50 W
VCC = 3.3 V
GND
50 W*
VTCLK
D
Figure 10. LVPECL Interface
*RTIN, Internal Input Termination Resistor
50 W*
VTCLK = VTCLK
LVDS
Driver
Z0 = 50 W
VCC = 3.3 V
GND
50 W*
VTCLK
D
Figure 11. LVDS Interface
*RTIN, Internal Input Termination Resistor
NB4N121K