8N3PG10MBKI-161 Data Sheet
Schematic Example
Figure 7 shows an example IDT8N3PG10MBKI-161 application
schematic in which the device is operated at VCC = +3.3V. The
schematic example focuses on functional connections and is
intended as an example only and may not represent the exact user
configuration. Refer to the pin description and functional tables in
the datasheet to ensure the logic control inputs are properly set. For
example OE, FSEL0 and FSEL1 can be configured from an FPGA
instead of pull up and pull down resistors as shown.
As with any high speed analog circuitry, the power supply pins are
vulnerable to random noise, so to achieve optimum jitter
performance isolation of the VCC pin from power supply is required.
In order to achieve the best possible filtering, it is recommended that
the placement of the filter components be on the device side of the
PCB as close to the power pins as possible. If space is limited, the
0.1µF capacitor on the VCC pin must be placed on the device side
with direct return to the ground plane though vias. The remaining
filter components can be on the opposite side of the PCB.
The input is driven by a DC coupled LVDS driver, though HCSL and
LVPECL are also compatible with the IDT CLK, nCLK differential
inputs. There are two LVPECL termination options shown; the
simple three resistor termination of R5, R6 and R7 and an AC
termination, used when coupling the IDT8N3PG10MBKI-161
LVPECL output stage to a different logic family receiver. Note that
the pull down resistors R8 and R9 that bias the LVPECL output
stage are to be placed on the IDT8N3PG10MBKI-161 side of the
PCB directly adjacent to pins 6 and 7 for best signal integrity. Most
often each output of a 3.3V LVPECL driver will be DC terminated
with a 130 pull up and an 82 pull down resistor at the 3.3V
LVPECL receiver. This is also a valid option with the
Power supply filter component recommendations are a general
guideline to be used for reducing external noise from coupling into
the devices. The filter performance is designed for a wide range of
noise frequencies. This low-pass filter starts to attenuate noise at
approximately 10kHz. If a specific frequency noise component is
known, such as switching power supplies frequencies, it is
recommended that component values be adjusted and if required,
additional filtering be added. Additionally, good general design
practices for power plane voltage stability suggests adding bulk
capacitance in the local area of all devices.
IDT8N3PG10MBKI-161, though the three resistor termination is
simpler in regard to component count and layout as well as lower in
power dissipation.
NOTE: This device package has an ePAD that is connected to
ground internally. The ePAD should be connected to GND on the
PCB through vias in order to improve heat dissipation.
©2016 Integrated Device Technology, Inc
15
Revision A January 28, 2016