ICS8534AY-01T IDT, Integrated Device Technology Inc, ICS8534AY-01T Datasheet - Page 12

• Manufacturer Part Number: ICS8534AY-01T
• Manufacturer: IDT, Integrated Device Technology Inc
• Type: Clock Driverr

Specifications of ICS8534AY-01T

• Number Of Clock Inputs: 2
• Mode Of Operation: Differential
• Output Frequency: 500MHz
• Output Logic Level: LVPECL
• Operating Supply Voltage (min): 3.135V
• Operating Supply Voltage (typ): 3.3V
• Operating Supply Voltage (max): 3.465V
• Package Type: TQFP EP
• Operating Temp Range: 0C to 85C
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Pin Count: 64
• Lead Free Status / RoHS Status: Not Compliant

Recommendations for Unused Input and Output Pins
Inputs:
CLK/nCLK Inputs
For applications not requiring the use of the differential input, both
CLK and nCLK can be left floating. Though not required, but for
additional protection, a 1kΩ resistor can be tied from CLK to
ground.
PCLK/nPCLK Inputs
For applications not requiring the use of the differential input, both
PCLK and nPCLK can be left floating. Though not required, but for
additional protection, a 1kΩ resistor can be tied from PCLK to
ground.
LVCMOS Control Pins
All control pins have internal pull-ups or pull-downs; additional
resistance is not required but can be added for additional
protection. A 1kΩ resistor can be used.
Termination for 3.3V LVPECL Outputs
The clock layout topology shown below is a typical termination for
LVPECL outputs. The two different layouts mentioned are
recommended only as guidelines.
FOUT and nFOUT are low impedance follower outputs that
generate ECL/LVPECL compatible outputs. Therefore, terminating
resistors (DC current path to ground) or current sources must be
used for functionality. These outputs are designed to drive 50
Figure 5A. 3.3V LVPECL Output Termination
IDT™ / ICS™ 3.3V LVPECL FANOUT BUFFER
ICS8534-01
LOW SKEW, 1-TO-22 DIFFERENTIAL-TO-3.3V LVPECL FANOUT BUFFER
RTT =
((V
FOUT
OH
+ V
OL
) / (V
1
CC
Z
Z
– 2)) – 2
o
o
= 50Ω
= 50Ω
Z
o
50Ω
RTT
50Ω
V
CC
FIN
- 2V
Ω
12
Outputs:
LVPECL Outputs
All unused LVPECL outputs can be left floating. We recommend
that there is no trace attached. Both sides of the differential output
pair should either be left floating or terminated.
transmission lines. Matched impedance techniques should be
used to maximize operating frequency and minimize signal
distortion. Figures 5A and 5B show two different layouts which are
recommended only as guidelines. Other suitable clock layouts may
exist and it would be recommended that the board designers
simulate to guarantee compatibility across all printed circuit and
clock component process variations.
Figure 5B. 3.3V LVPECL Output Termination
FOUT
Z
Z
o
o
= 50Ω
= 50Ω
ICS8534AY-01 REV. A OCTOBER 27, 2008
125Ω
84Ω
3.3V
125Ω
84Ω
FIN