ics8535-11 Holt Integrated Circuits, Inc., ics8535-11 Datasheet - Page 11

• Manufacturer Part Number: ics8535-11
• Description: Skew, 1-to-4, Crystal Oscillator/ Lvcmos-to-3.3v Lvpecl Fanout Buffer
• Manufacturer: Holt Integrated Circuits, Inc.

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
8535AG-11
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
F
L
L
] * (V
IGURE
] * (V
= V
= V
CC_MAX
CC_MAX
CC_MAX
CC_MAX
10 - LVPECL D
www.icst.com/products/hiperclocks.html
- V
– 1.7V
- V
OH_MAX
OL_MAX
– 1.0V
OL_MAX
OH_MAX
= 1.765V
= 2.465V
)
)
V
RIVER
Q1
CC
LVCMOS-
11
C
IRCUIT AND
L
OW
S
TO
KEW
RL
V
T
50
CC
ERMINATION
-3.3V LVPECL F
- 2V
V
, 1-
OUT
TO
-4, C
RYSTAL
ICS8535-11
ANOUT
O
REV. B JULY 27, 2001
SCILLATOR
B
UFFER
/