isl59311 Intersil Corporation, isl59311 Datasheet - Page 13

• Manufacturer Part Number: isl59311
• Description: Differential Video Amplifier With Common Mode Sync Encoder And Serial Digital Interface
• Manufacturer: Intersil Corporation

Power Dissipation Calculation
When switching at high speeds, or driving heavy loads, the
ISL59311 drive capability is ultimately limited by the rise in die
temperature brought about by internal power dissipation. For
reliable operation die temperature must be kept below T
(+125°C). It is necessary to calculate the power dissipation for
a given application prior to selecting package type. Power
dissipation may be calculated:
where:
• V
• V
• C
• C
• I
• f is frequency
Having obtained the application's power dissipation, the
maximum junction temperature can be calculated:
T
where:
• T
• T
• PD is the power dissipation calculated above
θ
application (package + PCB combination). Refer to the
Package Power Dissipation curves. See Technical Bulletin
389 (http://www.intersil.com/data/tb/TB389.pdf) for additional
QFN PCB layout information.
PD
JA
JMAX
S
S
JMAX
MAX
OUT
L
INT
is the thermal resistance, junction to ambient, of the
=
is the quiescent supply current
is the total power supply to the ISL59311 (= V
is the load capacitance
(
V
=
is the internal load capacitance (80pF max)
S
is the swing on the output (V
is the maximum ambient operating temperature
T
is the maximum junction temperature (+125°C)
×
MAX
I
S
)
×
+
4
Σ
1
Θ
(
JA
C
INT
×
PD
×
V
2
S
×
13
f
)
+
(
C
L
H
×
V
- V
2
OUT
L
)
×
f
)
CCD
)
JMAX
ISL59311
April 25, 2007
FN6372.3