AN1944 Freescale Semiconductor / Motorola, AN1944 Datasheet - Page 3

• Manufacturer Part Number: AN1944
• Description: Generating Temperature-Dependent IV Curves Using ADS
• Manufacturer: Freescale Semiconductor / Motorola

3 is useful. However, a more useful method of illustrating
the temperature dependence of IV curves is illustrated in
Figure 4.
(Normalized to 25°C) versus Temperature at Parametric
MOTOROLA SEMICONDUCTOR APPLICATION INFORMATION
The data gathered from the simulation shown in Figure
Figure 5. MRF9080 Simulated IV–Temperature Data
1.020
1.010
1.000
0.990
0.980
0.960
0.970
0.950
1.060
1.040
1.020
1.000
0.980
0.960
Figure 4. Generic Plot of Gate Source Voltage
(Normalized to Gate Source Voltage @ 25°C)
0
5
10
800 mA
15
20
25
30
Values of I
T, TEMPERATURE (°C)
T, TEMPERATURE (°C)
35
40
45
50
Freescale Semiconductor, Inc.
DQ
55
For More Information On This Product,
600 mA
60
2.5 A
65
70
75
Go to: www.freescale.com
1.0 A
80
I
DQ
85
5000 mA
4000 mA
3000 mA
2000 mA
1000 mA
= 5.0 A
90
95
100
macro in Microsoft Excel. This macro tests all values of I
(simulated) and compares them against desired values to
graph (600 mA, 800 mA and so on). When a tested I
value is within +/– 1% of the desired I
and V
and T
MRF9080 device. This data was taken under DC pulse
conditions in a controlled temperature environment. Each
measurement was performed quickly enough so that P
not contribute to the T
MEASURED VERSUS MODELED
between measured and simulated IV–Temperature behavior
from 600 mA to 3000 mA. At higher quiescent currents, the
correlation is not as strong. When designing temperature
compensation circuits, it is recommended that a circuit similar
to that shown in Figure 7 should be used.
The data set shown in Figure 5 was generated using a
Figure 6 shows the IV–Temperature data measured from an
A comparison of Figures 5 and 6 show a strong correlation
Figure 6. MRF9080 Measured IV–Temperature Data
1.020
1.010
1.000
0.990
0.980
0.970
0.960
0.950
0.940
GS
SNK
(Normalized to Gate Source Voltage @ 25°C)
0
are recorded. This process is repeated for all V
.
10
20
(device)
30
T, TEMPERATURE (°C)
40
.
50
60
DQ
, the temperature
70
80
AN1944
I
DQ
= 5.0 A
90
diss
2.5 A
0.6 A
3
did
DQ
DQ
100
GS