MK1493-05
DIFFERENTIAL SPREAD SPECTRUM CLOCK DRIVER CLOCK SYNTHESIZER
IDT™
DIFFERENTIAL SPREAD SPECTRUM CLOCK DRIVER 9
MK1493-05 REV J 051310
Application Information
Series Termination Resistor
Clock output traces should use series termination. To series
terminate a 50Ω trace (a commonly used trace impedance),
place a 33Ω resistor in series with the clock line, as close to
the clock output pin as possible. The nominal impedance of
the clock output is 20Ω.
Decoupling Capacitors
As with any high-performance mixed-signal IC, the
MK1493-05 must be isolated from system power supply
noise to perform optimally.
Decoupling capacitors of 0.01µF must be connected
between each VDD and the PCB ground plane.
PCB Layout Recommendations
For optimum device performance and lowest output phase
noise, the following guidelines should be observed.
1) Each 0.01µF decoupling capacitor should be mounted on
the component side of the board as close to the VDD pin as
possible. No vias should be used between decoupling
capacitor and VDD pin. The PCB trace to VDD pin should
be kept as short as possible, as should the PCB trace to the
ground via. Distance of the ferrite bead and bulk decoupling
from the device is less critical.
2) To minimize EMI, and obtain the best signal integrity, the
33Ω series termination resistor should be placed close to
the clock output.
3) An optimum layout is one with all components on the
same side of the board, minimizing vias through other signal
layers (the ferrite bead and bulk decoupling capacitor can be
mounted on the back). Other signal traces should be routed
away from the MK1493-05.
This includes signal traces just underneath the device, or on
layers adjacent to the ground plane layer used by the device.
Absolute Maximum Ratings
Stresses above the ratings listed below can cause permanent damage to the MK1493-05. These ratings are stress
ratings only. Functional operation of the device at these or any other conditions above those indicated in the
operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for
extended periods can affect product reliability. Electrical parameters are guaranteed only over the recommended
operating temperature range.
Item Rating
Supply Voltage, VDD, VDDA 5.5 V
All Inputs and Outputs -0.5 V to VDD+0.5 V
Ambient Operating Temperature 0 to +70° C
Storage Temperature -65 to +150° C
Junction Temperature 125° C
Soldering Temperature 260° C
ESD Protection (Input) 2000 V min. (HBM)
