ICS8532AY-01 ICST [Integrated Circuit Systems], ICS8532AY-01 Datasheet - Page 10

• Manufacturer Part Number: ICS8532AY-01
• Description: LOW SKEW, 1-TO-17 DIFFERENTIAL-TO-3.3V LVPECL FANOUT BUFFER
• Manufacturer: ICST [Integrated Circuit Systems]

3. Calculations and Equations.
The purpose of this section is to derive the power dissipated into the load.
LVPECL output driver circuit and termination are shown in Figure 10.
T
voltage of 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
Pd_L = [(V
Pd_H = [(2.465V - (3.465V - 2V))/50 ] * (3.465V - 2.465V) = 20mW
Pd_L = [(1.765V - (3.465V - 2V))/50 ] * (3.465V - 1.765V) = 10.2mW
Total Power Dissipation per output pair = Pd_H + Pd_L = 30.2mW
8532AY-01
o calculate worst case power dissipation into the load, use the following equations which assume a 50 load, and a termination
•
•
For logic high, V
Using V
For logic low, V
Using V
OL_MAX
OH_MAX
CC
- 2V.
– (V
CC_MAX
CC_MAX
– (V
CC_MAX
CC_MAX
= 3.465, this results in V
= 3.465, this results in V
OUT
OUT
- 2V))/R
- 2V))/R
= V
= V
OL_MAX
OH_MAX
L
Figure 10 - LVPECL Driver Circuit and Termination
L
] * (V
] * (V
= V
= V
CC_MAX
CC_MAX
CC_MAX
CC_MAX
www.icst.com/products/hiperclocks.htlm
- V
– 1.7V
- V
OH_MAX
OL_MAX
– 1.0V
OL_MAX
OH_MAX
= 1.765V
= 2.465V
)
)
D
IFFERENTIAL
V
Q1
CCO
10
-
TO
R L
V
50
-3.3V LVPECL F
CCO
V
- 2V
OUT
L
OW
ICS8532-01
S
ANOUT
KEW
REV. B AUGUST 9, 2001
, 1-
B
TO
UFFER
-17