The tool provides a universal simple method of representing the thermal character of electronics by Interpreting values from datasheet or measurement. It allows a power plot using a SPICE simulator to accurate represent package temperatures, which can be employed as vehicle to cross compare techniques.
2. Why thermal model is needed?
Smaller chip reduces parasitic effect.
Less parasitic allows for high frequency with less switching loss.
Efficient high frequency allows further size reduction.
In order to make a smaller and higher power switch, the thermal limit
must be pushed back.
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3. What is thermal impedance
Silicon chip
Solder/Wire
Copper frame
Epoxy
Tj Tam b
Z th
power
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4. What is Thermal impedance 4
t
Foster circuit Z th t Rn 1 exp
n 1 C n Rn
Foster-equivalent model have a real physical meaning: each RC cell
represents the contribution to the thermal impedance of a given part
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5. Deliverable of the Our Tool
a universal and simple method of representing the
thermal character of a device
Interpret values from datasheet or measurement
The tool would allow a power plot using a SPICE
simulator to accurate represent package temperatures.
Employed as vehicle to cross compare techniques.
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7. Results
Temperature response to oscilloscope waveform
Temperature Limit
80 80
70 70
Junction Temperature [ C]
60 60
Input power [W]
50 50
40 40
30 30
20 20
Junction temperature
10 Input Power 10
0 0
0 10 20 30 40 50
Time [us]
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8. Application 5 yr
300 100%
beneficial of the tool
250
80%
Quantity in Test
Controlled lifetime 200
Failure Rate
60%
150
Reliable performance 100
40%
Life e c/TJ 20%
Reduced manufacture cost 50
0 0%
Reduced maintenance costs 1 10 100 1000 10000
Test Time (Hours)
Temperature Operating Life test underwent using JESD22-A108 standard
Useful life period
Failure rate
EFR IFR (Intrinsic Failure Rate) Wearout
low, constant period
0 Time
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9. Advantage
Related Art benchmark
Supplier A Supplier B
Foster networks RC networks Cauer RC networks included in
included in the datasheet the datasheet
Supplier C Supplier D
Use two additional pins Supplier E
Online calculator and some
for junction temperature Cauer RC networks included in a apps
thermal RC networks
from RC networks note for each part
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On the other hand, the suppliers and manufacturers keep shrinking product size for cost down Technicallly, see bove
Regardless of the operator or the specifics, the network is a point-to-multipoint distribution scheme, where a signal splits many times and can travel long distances from its point of origination to its destination at a customer premises. These splits and transmission distance create loss that system-level amplifiers at different points in the network must compensate.
The clear trend in the industry is to increased output levels from the power amplifiers. With bandwidth consumption increasing, nodes can handle fewer homes before usage exceeds capacity. A common solution is to offload bandwidth by inserting more nodes into a network. The result of these additional nodes is to increase splitting of the input signals before they reach a customer premises.