ICS85352AYI IDT, Integrated Device Technology Inc, ICS85352AYI Datasheet - Page 14

• Manufacturer Part Number: ICS85352AYI
• Manufacturer: IDT, Integrated Device Technology Inc
• Type: Clock Multiplexerr

Specifications of ICS85352AYI

• Number Of Clock Inputs: 2
• Mode Of Operation: Differential
• Output Frequency: 700MHz
• 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: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 48
• Lead Free Status / Rohs Status: Not Compliant

ICS85352I Data Sheet
3. Calculations and Equations.
The purpose of this section is to calculate the power dissipation for the LVPECL output pairs.
LVPECL output driver circuit and termination are shown in Figure 5.
Figure 5. LVPECL Driver Circuit and Termination
T
V
Pd_H is power dissipation when the output drives high.
Pd_L is the power dissipation when the output drives low.
Pd_H = [(V
[(2V – 0.9V)/50Ω] * 0.9V = 19.8mW
Pd_L = [(V
[(2V – 1.7V)/50Ω] * 1.7V = 10.2mW
Total Power Dissipation per output pair = Pd_H + Pd_L = 30mW
ICS85352AYI REVISION B JULY 6, 2010
o calculate worst case power dissipation into the load, use the following equations which assume a 50Ω load, and a termination voltage of
CCO
•
•
– 2V.
For logic high, V
(V
For logic low, V
(V
OL_MAX
OH_MAX
CCO_MAX
CCO_MAX
– (V
– (V
– V
– V
CCO_MAX
CCO_MAX
OH_MAX
OUT
OL_MAX
OUT
= V
V
= V
Q1
CCO
) = 1.7V
) = 0.9V
OL_MAX
– 2V))/R
– 2V))/R
OH_MAX
= V
L
= V
L
] * (V
] * (V
CCO_MAX
CCO_MAX
COC_MAX
CCO_MAX
RL
50Ω
V
CCO
– 1.7V
– 0.9V
-
V
2V
– V
OUT
– V
OL_MAX
OH_MAX
) = [(2V – (V
) = [(2V – (V
14
CCO_MAX
CCO_MAX
– V
– V
OL_MAX
OH_MAX
12 BIT, 2-TO-1, 3.3V, 2.5V LVPECL CLOCK BUFFER
))/R
))/R
L]
L
* (V
] * (V
©2010 Integrated Device Technology, Inc.
CCO_MAX
CCO_MAX
– V
– V
OL_MAX
OH_MAX
) =
) =