ics843-75 Integrated Device Technology, ics843-75 Datasheet - Page 9

• Manufacturer Part Number: ics843-75
• Description: Low Jitter Xtal-input Lvpecl-output 75-mhz Clock Synthesizer
• Manufacturer: Integrated Device Technology

IDT™ / ICS™ 75MHZ, LVCMOS, LVPECL DUAL OUTPUT OSCILLATOR
ICS843-75
75MHZ, LVCMOS, LVPECL DUAL OUTPUT OSCILLATOR
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 3.
T
termination
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
[(2V - 0.9V)/50 ] * 0.9V = 19.8mW
Pd_L = [(V
[(2V - 1.7V)/50 ] * 1.7V = 10.2mW
Total Power Dissipation per output pair = Pd_H + Pd_L = 30mW
843AG-75
o calculate worst case power dissipation into the load, use the following equations which assume a 50
•
•
For logic high, V
(V
For logic low, V
(V
OL_MAX
OH_MAX
CCO_MAX
CCO_MAX
CC
- 2V.
Integrated
Circuit
Systems, Inc.
– (V
– (V
- V
- V
CC_MAX
OH_MAX
OL_MAX
CC_MAX
OUT
OUT
- 2V))/R
) = 1.7V
) = 0.9V
- 2V))/R
= V
= V
OL_MAX
OH_MAX
L
L
] * (V
] * (V
F
= V
= V
IGURE
CC_MAX
CC_MAX
CC_MAX
CC_MAX
www.icst.com/products/hiperclocks.html
3. LVPECL D
- V
– 1.7V
- V
– 0.9V
OL_MAX
OH_MAX
) = [(2V - (V
) = [(2V - (V
RIVER
V
Q1
CC
9
9
C
CC _MAX
CC _MAX
IRCUIT AND
- V
- V
OL_MAX
OH_MAX
T
ERMINATION
RL
V
50
)) /R
CC
)) /R
- 2V
V
75MH
L
] * (V
L
OUT
] * (V
CC_MAX
CC_MAX
D
UAL
Z
, LVCMOS, LVPECL
- V
- V
OL_MAX
O
OH_MAX
UTPUT
) =
) =
load, and a
REV. A JANUARY 9, 2006
O
SCILLATOR
ICS843-75
TSD