lm7171amwgflqv National Semiconductor Corporation, lm7171amwgflqv Datasheet - Page 19

• Manufacturer Part Number: lm7171amwgflqv
• Description: Lm7171qml Very High Speed, High Output Current, Voltage Feedback Amplifier
• Manufacturer: National Semiconductor Corporation

Power Dissipation
The maximum power allowed to dissipate in a device is de-
fined as:
Where
θ
For example, for the LM7171 in a Ceramic SOIC package, the
maximum power dissipation at 25°C ambient temperature is
680 mW.
Thermal resistance, θ
size, package size and package material. The smaller the die
size and package, the higher θ
package has a lower thermal resistance (106°C/W) than that
of the Ceramic SOIC (182°C/W). Therefore, for higher dissi-
pation capability, use an 8-pin DIP package.
The total power dissipated in a device can be calculated as:
P
connected at the output. P
vice with a load connected at the output; it is not the power
dissipated by the load.
Furthermore,
For example, the total power dissipated by the LM7171 with
V
Q
S
PD
T
T
P
P
P
= ±15V and output voltage of 10V into 1 kΩ is
is the quiescent power dissipated in a device with no load
JA
J(max)
A
Q
L
D
: = output current × (voltage difference between sup-
: = supply current × total supply voltage with no load
FIGURE 6. The LM7171 Driving a 150 pF Load
= P
is the power dissipation in a device
is the maximum junction temperature
is the ambient temperature
is the thermal resistance of a particular package
ply voltage and output voltage of the same side of
supply voltage)
Q
+ P
with a 50Ω Isolation Resistor
L
P
D
JA
= (T
, depends on parameters such as die
P
D
L
J(max)
= P
is the power dissipated in the de-
Q
− T
JA
+ P
becomes. The 8-pin DIP
A
L
)/θ
JA
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Application Circuit
= (6.5 mA) × (30V) + (10 mA) × (15V − 10V)
= 195 mW + 50 mW
= 245 mW
Fast Instrumentation Amplifier
Multivibrator
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