Jorge Garcia

Fusion 360 Community Manager

Heath Houghton

Product Manager for Fluid Simulation Products

Fusion 360 (Case Study)Creating a Lab Power Supply

About the speaker

Jorge Garcia

I'm a Community Manager for Fusion 360

Electronics/EAGLE, here at Autodesk. I have been

working with EAGLE for 10 years. I earned my

Bachelor’s Degree in Electrical Engineering from

Florida International University in 2008. I love

electronics and building projects focusing on power and

control applications. I have an affinity for embedded

systems and programming.

About the speaker

Heath Houghton

Heath Houghton is the product manager for fluids simulation

products. As Product Manager, Heath guides the development

efforts and roadmap decisions for flow and thermal simulation

projects. Heath joined Autodesk with the acquisition of Blue Ridge

Numerics CFdesign. He was in a technical role with Blue Ridge

Numerics for several years and he continued in that role with

Autodesk before transitioning to Product Manager. Heath has over

20 years of experience with both fluids and structural simulation

tools. In his spare time, Heath enjoys archery and training his bird

dogs.

Design Theory of Operation

Schematic Overview

Input Rectifier

• Takes 120VAC(BE CAREFUL!) and steps it

down to 24VAC(34V peak)

• Contains some basic safety features by

incorporating a fuse and power off switch

• The diodes are arranged in a basic

configuration known as a Bridge rectifier

which is the key component for converting

AC to DC

• The 4700uF capacitor is used to smooth the

ripple of the rectified waveform to get us

DC voltage.

Pre-Regulator

• Very useful, but not very common

• Dissipates part of the power sparing

the more expensive and sensitive

regulator.

• The control circuit determines when

the power resistor is in circuit or if it

should be bypassed.

• BD438 is used as a switch so it will

dissipate very little power

Control Circuit

• All of the op amps are setup as comparators, when

the measured value exceeds the set value their

outputs will go high.

• Diodes D3,D4, and Resistor R6 form and AND gate. In

order for IC2B to go high and bypass the power

resistor IC2C and IC2D have to be high.

How to determine thresholds- MATH

• From the schematic we can determine that the power dissipation of the regulator is defined by

• 𝑷𝒓𝒆𝒈 = 𝑽𝒉 − 𝑽𝒐𝒖𝒕 𝑰 − 𝑹𝑰𝟐

o The Maximum dissipation can be calculated by taking the derivative and setting that to 0. For a given R value we

can find the current at which max dissipation occurs plug it into the above equation and find out the peak dissipation

for a given power resistor value and output voltage.

▪ 𝐼 =𝑉ℎ−𝑉𝑜𝑢𝑡

2𝑅is the current that will yield the maximum power dissipation in the regulator

• Determining the optimal balance is a tradeoff between the resistor value and being able to provide the

necessary output voltage.

o A large resistor will allow us to have low dissipation in the Regulator but will limit what output current and voltages

we can output.

How to determine thresholds - VISUALLY

• The top table shows the regulator dissipation

with the resistor in-circuit for every

combination of current and output voltage

o All cells larger than zero are green. Cells less

than 0 are unachievable. The fringes have to

confirmed to make sure they will work since the

regulator needs some overhead

• Bottom table is no resistor in circuit

o All cells whose dissipation is greater than 25W

are red

• Make sure all red combinations can have the

resistor in circuit. The unobtainable regions in

the top table require the resistor to be

bypassed

R 10

VH 34

V(volts) | I(amps)> Dissipation of Regulator with a Resistor Pre-reg

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5

1.25 3.175 6.15 8.925 11.5 13.875 16.05 18.025 19.8 21.375 22.75 23.925 24.9 25.675 26.25 26.625

2.5 3.05 5.9 8.55 11 13.25 15.3 17.15 18.8 20.25 21.5 22.55 23.4 24.05 24.5 24.75

3.75 2.925 5.65 8.175 10.5 12.625 14.55 16.275 17.8 19.125 20.25 21.175 21.9 22.425 22.75 22.875

5 2.8 5.4 7.8 10 12 13.8 15.4 16.8 18 19 19.8 20.4 20.8 21 21

6.25 2.675 5.15 7.425 9.5 11.375 13.05 14.525 15.8 16.875 17.75 18.425 18.9 19.175 19.25 19.125

7.5 2.55 4.9 7.05 9 10.75 12.3 13.65 14.8 15.75 16.5 17.05 17.4 17.55 17.5 17.25

8.75 2.425 4.65 6.675 8.5 10.125 11.55 12.775 13.8 14.625 15.25 15.675 15.9 15.925 15.75 15.375

10 2.3 4.4 6.3 8 9.5 10.8 11.9 12.8 13.5 14 14.3 14.4 14.3 14 13.5

11.25 2.175 4.15 5.925 7.5 8.875 10.05 11.025 11.8 12.375 12.75 12.925 12.9 12.675 12.25 11.625

12.5 2.05 3.9 5.55 7 8.25 9.3 10.15 10.8 11.25 11.5 11.55 11.4 11.05 10.5 9.75

13.75 1.925 3.65 5.175 6.5 7.625 8.55 9.275 9.8 10.125 10.25 10.175 9.9 9.425 8.75 7.875

15 1.8 3.4 4.8 6 7 7.8 8.4 8.8 9 9 8.8 8.4 7.8 7 6

16.25 1.675 3.15 4.425 5.5 6.375 7.05 7.525 7.8 7.875 7.75 7.425 6.9 6.175 5.25 4.125

17.5 1.55 2.9 4.05 5 5.75 6.3 6.65 6.8 6.75 6.5 6.05 5.4 4.55 3.5 2.25

18.75 1.425 2.65 3.675 4.5 5.125 5.55 5.775 5.8 5.625 5.25 4.675 3.9 2.925 1.75 0.375

20 1.3 2.4 3.3 4 4.5 4.8 4.9 4.8 4.5 4 3.3 2.4 1.3 0 -1.5

21.25 1.175 2.15 2.925 3.5 3.875 4.05 4.025 3.8 3.375 2.75 1.925 0.9 -0.325 -1.75 -3.375

22.5 1.05 1.9 2.55 3 3.25 3.3 3.15 2.8 2.25 1.5 0.55 -0.6 -1.95 -3.5 -5.25

23.75 0.925 1.65 2.175 2.5 2.625 2.55 2.275 1.8 1.125 0.25 -0.825 -2.1 -3.575 -5.25 -7.125

25 0.8 1.4 1.8 2 2 1.8 1.4 0.8 0 -1 -2.2 -3.6 -5.2 -7 -9

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5

1.25 3.275 6.55 9.825 13.1 16.375 19.65 22.925 26.2 29.475 32.75 36.025 39.3 42.575 45.85 49.125

2.5 3.15 6.3 9.45 12.6 15.75 18.9 22.05 25.2 28.35 31.5 34.65 37.8 40.95 44.1 47.25

3.75 3.025 6.05 9.075 12.1 15.125 18.15 21.175 24.2 27.225 30.25 33.275 36.3 39.325 42.35 45.375

5 2.9 5.8 8.7 11.6 14.5 17.4 20.3 23.2 26.1 29 31.9 34.8 37.7 40.6 43.5

6.25 2.775 5.55 8.325 11.1 13.875 16.65 19.425 22.2 24.975 27.75 30.525 33.3 36.075 38.85 41.625

7.5 2.65 5.3 7.95 10.6 13.25 15.9 18.55 21.2 23.85 26.5 29.15 31.8 34.45 37.1 39.75

8.75 2.525 5.05 7.575 10.1 12.625 15.15 17.675 20.2 22.725 25.25 27.775 30.3 32.825 35.35 37.875

10 2.4 4.8 7.2 9.6 12 14.4 16.8 19.2 21.6 24 26.4 28.8 31.2 33.6 36

11.25 2.275 4.55 6.825 9.1 11.375 13.65 15.925 18.2 20.475 22.75 25.025 27.3 29.575 31.85 34.125

12.5 2.15 4.3 6.45 8.6 10.75 12.9 15.05 17.2 19.35 21.5 23.65 25.8 27.95 30.1 32.25

13.75 2.025 4.05 6.075 8.1 10.125 12.15 14.175 16.2 18.225 20.25 22.275 24.3 26.325 28.35 30.375

15 1.9 3.8 5.7 7.6 9.5 11.4 13.3 15.2 17.1 19 20.9 22.8 24.7 26.6 28.5

16.25 1.775 3.55 5.325 7.1 8.875 10.65 12.425 14.2 15.975 17.75 19.525 21.3 23.075 24.85 26.625

17.5 1.65 3.3 4.95 6.6 8.25 9.9 11.55 13.2 14.85 16.5 18.15 19.8 21.45 23.1 24.75

18.75 1.525 3.05 4.575 6.1 7.625 9.15 10.675 12.2 13.725 15.25 16.775 18.3 19.825 21.35 22.875

20 1.4 2.8 4.2 5.6 7 8.4 9.8 11.2 12.6 14 15.4 16.8 18.2 19.6 21

21.25 1.275 2.55 3.825 5.1 6.375 7.65 8.925 10.2 11.475 12.75 14.025 15.3 16.575 17.85 19.125

22.5 1.15 2.3 3.45 4.6 5.75 6.9 8.05 9.2 10.35 11.5 12.65 13.8 14.95 16.1 17.25

23.75 1.025 2.05 3.075 4.1 5.125 6.15 7.175 8.2 9.225 10.25 11.275 12.3 13.325 14.35 15.375

25 0.9 1.8 2.7 3.6 4.5 5.4 6.3 7.2 8.1 9 9.9 10.8 11.7 12.6 13.5

How to determine thresholds - VISUALLY

• After analyzing the tables it was

determined that the bordered

region would need the resistor

cut out.

o Vout >= 16.5

o AND I >= 0.75

• We are giving up some areas

where the resistor could protect

the regulator but worst case

scenario the regulator only has

to dissipate 25W in the

bordered area

R 10

VH 34

V(volts) | I(amps)> Dissipation of Regulator with a Resistor Pre-reg

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5

1.25 3.175 6.15 8.925 11.5 13.875 16.05 18.025 19.8 21.375 22.75 23.925 24.9 25.675 26.25 26.625

2.5 3.05 5.9 8.55 11 13.25 15.3 17.15 18.8 20.25 21.5 22.55 23.4 24.05 24.5 24.75

3.75 2.925 5.65 8.175 10.5 12.625 14.55 16.275 17.8 19.125 20.25 21.175 21.9 22.425 22.75 22.875

5 2.8 5.4 7.8 10 12 13.8 15.4 16.8 18 19 19.8 20.4 20.8 21 21

6.25 2.675 5.15 7.425 9.5 11.375 13.05 14.525 15.8 16.875 17.75 18.425 18.9 19.175 19.25 19.125

7.5 2.55 4.9 7.05 9 10.75 12.3 13.65 14.8 15.75 16.5 17.05 17.4 17.55 17.5 17.25

8.75 2.425 4.65 6.675 8.5 10.125 11.55 12.775 13.8 14.625 15.25 15.675 15.9 15.925 15.75 15.375

10 2.3 4.4 6.3 8 9.5 10.8 11.9 12.8 13.5 14 14.3 14.4 14.3 14 13.5

11.25 2.175 4.15 5.925 7.5 8.875 10.05 11.025 11.8 12.375 12.75 12.925 12.9 12.675 12.25 11.625

12.5 2.05 3.9 5.55 7 8.25 9.3 10.15 10.8 11.25 11.5 11.55 11.4 11.05 10.5 9.75

13.75 1.925 3.65 5.175 6.5 7.625 8.55 9.275 9.8 10.125 10.25 10.175 9.9 9.425 8.75 7.875

15 1.8 3.4 4.8 6 7 7.8 8.4 8.8 9 9 8.8 8.4 7.8 7 6

16.25 1.675 3.15 4.425 5.5 6.375 7.05 7.525 7.8 7.875 7.75 7.425 6.9 6.175 5.25 4.125

17.5 1.55 2.9 4.05 5 5.75 6.3 6.65 6.8 6.75 6.5 6.05 5.4 4.55 3.5 2.25

18.75 1.425 2.65 3.675 4.5 5.125 5.55 5.775 5.8 5.625 5.25 4.675 3.9 2.925 1.75 0.375

20 1.3 2.4 3.3 4 4.5 4.8 4.9 4.8 4.5 4 3.3 2.4 1.3 0 -1.5

21.25 1.175 2.15 2.925 3.5 3.875 4.05 4.025 3.8 3.375 2.75 1.925 0.9 -0.325 -1.75 -3.375

22.5 1.05 1.9 2.55 3 3.25 3.3 3.15 2.8 2.25 1.5 0.55 -0.6 -1.95 -3.5 -5.25

23.75 0.925 1.65 2.175 2.5 2.625 2.55 2.275 1.8 1.125 0.25 -0.825 -2.1 -3.575 -5.25 -7.125

25 0.8 1.4 1.8 2 2 1.8 1.4 0.8 0 -1 -2.2 -3.6 -5.2 -7 -9

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5

1.25 3.275 6.55 9.825 13.1 16.375 19.65 22.925 26.2 29.475 32.75 36.025 39.3 42.575 45.85 49.125

2.5 3.15 6.3 9.45 12.6 15.75 18.9 22.05 25.2 28.35 31.5 34.65 37.8 40.95 44.1 47.25

3.75 3.025 6.05 9.075 12.1 15.125 18.15 21.175 24.2 27.225 30.25 33.275 36.3 39.325 42.35 45.375

5 2.9 5.8 8.7 11.6 14.5 17.4 20.3 23.2 26.1 29 31.9 34.8 37.7 40.6 43.5

6.25 2.775 5.55 8.325 11.1 13.875 16.65 19.425 22.2 24.975 27.75 30.525 33.3 36.075 38.85 41.625

7.5 2.65 5.3 7.95 10.6 13.25 15.9 18.55 21.2 23.85 26.5 29.15 31.8 34.45 37.1 39.75

8.75 2.525 5.05 7.575 10.1 12.625 15.15 17.675 20.2 22.725 25.25 27.775 30.3 32.825 35.35 37.875

10 2.4 4.8 7.2 9.6 12 14.4 16.8 19.2 21.6 24 26.4 28.8 31.2 33.6 36

11.25 2.275 4.55 6.825 9.1 11.375 13.65 15.925 18.2 20.475 22.75 25.025 27.3 29.575 31.85 34.125

12.5 2.15 4.3 6.45 8.6 10.75 12.9 15.05 17.2 19.35 21.5 23.65 25.8 27.95 30.1 32.25

13.75 2.025 4.05 6.075 8.1 10.125 12.15 14.175 16.2 18.225 20.25 22.275 24.3 26.325 28.35 30.375

15 1.9 3.8 5.7 7.6 9.5 11.4 13.3 15.2 17.1 19 20.9 22.8 24.7 26.6 28.5

16.25 1.775 3.55 5.325 7.1 8.875 10.65 12.425 14.2 15.975 17.75 19.525 21.3 23.075 24.85 26.625

17.5 1.65 3.3 4.95 6.6 8.25 9.9 11.55 13.2 14.85 16.5 18.15 19.8 21.45 23.1 24.75

18.75 1.525 3.05 4.575 6.1 7.625 9.15 10.675 12.2 13.725 15.25 16.775 18.3 19.825 21.35 22.875

20 1.4 2.8 4.2 5.6 7 8.4 9.8 11.2 12.6 14 15.4 16.8 18.2 19.6 21

21.25 1.275 2.55 3.825 5.1 6.375 7.65 8.925 10.2 11.475 12.75 14.025 15.3 16.575 17.85 19.125

22.5 1.15 2.3 3.45 4.6 5.75 6.9 8.05 9.2 10.35 11.5 12.65 13.8 14.95 16.1 17.25

23.75 1.025 2.05 3.075 4.1 5.125 6.15 7.175 8.2 9.225 10.25 11.275 12.3 13.325 14.35 15.375

25 0.9 1.8 2.7 3.6 4.5 5.4 6.3 7.2 8.1 9 9.9 10.8 11.7 12.6 13.5

Main Regulator

• The circuit provides an Adjustable output

voltage to power your circuits.

• Diodes D1, and D2 protect the regulator by

making sure it doesn’t get reverse biased.

• R10 allows the user to set the voltage from

1.25-24VDC

• The V_Meas signal feeds one of the

comparators

Current Measurement

• The current measured signal feeds the other

comparator in the control circuit.

• R8,R14,R15 could technically be replaced with a

30k resistor, however sometimes especially in

large scale production it’s more cost effective to

limit the number of different component values

and order a larger quantity of the limited subset.

This is a good example.

• The voltage developed across R2, is amplified

and turned into a voltage by IC2A and Q4

How Fusion Electronics speeds up design

Collaboration on another level

• All data is versioned controlled

o You can recover from any bad saves by promoting a previous version

• All team members have access to the latest version of the data in real-time

o Allows for easy communication of changes

o Engineers from different disciplines can effectively work together

▪ ECAD-MCAD Workflows

▪ E-cooling simulation

Advanced Routing Features

• This power supply circuitry operates near DC

o From an electronics point of the view; all interconnects are transparent and intrinsic(aka parasitic)

impedances can be ignored

o This means that the layout itself is non-critical(generally speaking) and is a good candidate for a first time

PCB since the design requirements aren’t difficult to meet. We just have to make sure the traces are thick

enough to handle the current.

o This also means that we can leverage more of the automation that Fusion 360 Electronics/EAGLE provide to

speed up our design

Simplified Manufacturing Process

• The CAM processor export gives a gentle introduction to generating Gerber files and drill files since it

covers most use cases.

o With one click you can generate all your manufacturing data and send it to your manufacturer

o It analyzes your design and picks the most suitable template.

Demonstration

Please watch the demonstration here:https://drive.autodesk.com/new/de29810b9/shares/SH56a43QTfd62c1cd968b3008281353a8000

Or watch the demonstration in context at our class at AU2020

ECAD-MCAD Workflows

3DPCB from 2D in one click

• Fusion ships with many libraries that already include 3D models of components

o You can also assign your own 3D models when you make components

• This allows for a seamless transition between 2D and 3D PCB with no additional effort required of the

designer.

Designing an Enclosure from the 3D PCB

• 2 Main workflows

o Use PCB as basis for enclosure

▪ Insert the PCB into a new design and then draw the enclosure.

o Use the enclosure as the basis for the PCB

▪ PCB derive workflow allows the enclosure to drive the PCB design

• For this design we used the first workflow

Demonstration

Watch demo video here:https://drive.autodesk.com/new/de29810b9/shares/SH56a43QTfd62c1cd968a521b4e4325eb4e5

Or watch it in context at our class in AU2020

E-cooling

Baseline Enclosure

The transistor is not attached to a heat sink

• Natural convection

• 50 watt heat generation

Large Heat Sink

Large heat sink with no fan. Enclosure hidden for clarity.

Overall air flow and solid temperatures are shown. Maximum

Temperature over 900C.

Cross section at the transistor. Maximum Temperature over 900C.

Fan Flow Out

Large Heat Sink Added

The transistor is now attached to a large heat sink

• Natural convection

Large Heat Sink

Large heat sink with no fan. Overall air flow and solid

temperatures are shown. Maximum Temperature 648C.

Overall airflow and temperatures. Enclosure hidden to see internal

results. Maximum Temperature 648C.

Fan Flow Out

Heat Load Divided

The heat load is divided over our regulator and power resistor

each attached to their own heat sink

• 41 cfm fan also added

o 1st we try flow pulled out of the enclosure

o 2nd we try flow pulled into the enclosure

Fan Flow Out

Fan flow rate into enclosure. Overall air flow and solid

temperatures are shown. Maximum Temperature 345C.

Cross section of air flow. Maximum Temperature 345C.

Fan Flow Out

Fan Flow In

Fan flow rate into enclosure. Overall air flow and solid

temperatures are shown. Maximum Temperature 115C.

Cross section of air flow. Maximum Temperature 115C.

Fan Flow In

Demonstration

Watch the demo video here:https://drive.autodesk.com/new/de29810b9/shares/SH56a43QTfd62c1cd96828c30d78f9374618

Or watch it in context in our class at AU2020

Wrap-up

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