PCB Forum - Recent Threads

Help me convert allegro .alg file to Altium .pcbdoc

abtAmit — Fri, 05 Jun 2026 09:28:00 GMT

Hi everyone,

I recently came across the SK-AM62P-LP Evaluation board on TI.com. TI included the design files, and I thought analyzing them would be a great way to expand my knowledge of PCB design.

The project seems to have been designed using Allegro, and the provided file has an .alg extension. Since I don't have the software to open or convert this, could someone who has Altium Designer do me a huge favor?

I've attached the file. If anyone is kind enough to convert it into a .PcbDoc format and attach it in a reply, I would really appreciate it. Thanks in advance for the help!"

[View:/cfs-file/__key/communityserver-discussions-components-files/76/5873.PROC164E2_5F00_BRD.zip:415:123]

RE: Help me convert allegro .alg file to Altium .pcbdoc

beacon_dave — Fri, 05 Jun 2026 19:56:22 GMT

[quote userid="521287" url="~/products/pcbprototyping/f/forum/57016/help-me-convert-allegro-alg-file-to-altium-pcbdoc/235992"]i dont think i could visually inspect all 12 or more layer on the physical PC motherboard.[/quote]

You could perhaps use the included Gerber files for each layer to achieve that ?

Also looks like KiCad has a Gerber Viewer which can Export a Gerber to KiCad PCB.

https://www.kicad.org/discover/gerber-viewer/

Note though:

"....Converting to gerbers will not create a normal KiCad PCB design, it will be editable representation of the copper from the gerber..."

So you could perhaps try exporting from KiCad PCB to EasyEDA.

RE: Help me convert allegro .alg file to Altium .pcbdoc

abtAmit — Fri, 05 Jun 2026 19:15:35 GMT

i simple words.
i am currently using EasyEDA for pcb designing.
now i want to check the pcb layout of the SK-AM62P-LP.
but the problem is i cannot import it directly in easyeda, thats why i thought if someone could convert that alg to pcbdoc file i could import and inspect it.

RE: Help me convert allegro .alg file to Altium .pcbdoc

shabaz — Fri, 05 Jun 2026 19:03:40 GMT

Are we supposed to guess your goal? Guessing from your response you've implied the goal is not to learn a CAD tool, but possibly to learn *something* at a level that you are unable to do from visual inspection.

By importing from one format to another (and in your case across three formats it seems), you will almost certainly lose any layer attributes, distances between planes, probably even the link between the PCB and schematic (KiCad only imports the PCB as far as I can see) so you've straight away lost detail.

You need a goal before a plan.

RE: Help me convert allegro .alg file to Altium .pcbdoc

abtAmit — Fri, 05 Jun 2026 18:52:40 GMT

[quote userid="123345" url="~/products/pcbprototyping/f/forum/57016/help-me-convert-allegro-alg-file-to-altium-pcbdoc/235990"]you can learn a lot from visual inspection of existing PCBs; for instance, pick any PC motherboard and look at it.[/quote]

i dont think i could visually inspect all 12 or more layer on the physical PC motherboard.
i am using easyeda, my plan is to get the .pcbdoc file and import it in EasyEDA.

RE: Help me convert allegro .alg file to Altium .pcbdoc

shabaz — Fri, 05 Jun 2026 17:13:04 GMT

Hi,

It's unclear what problem you're trying to solve. If it's to learn a CAD tool, then importing from one format to another is one of the worst ways (CAD tools will use basic primitives and won't pick the best way to convert shapes and holes from one system to another, whereas someone designing the footprints will pick more suitable features in their CAD system).

If it's to learn about PCB features and not the CAD tool itself, then you can learn a lot from visual inspection of existing PCBs; for instance, pick any PC motherboard and look at it.

RE: Help me convert allegro .alg file to Altium .pcbdoc

abtAmit — Fri, 05 Jun 2026 15:53:51 GMT

i am using easyeda, my plan is to get the .pcbdoc file and import it in EasyEDA.
i will try KiCAD as you suggested.
which PCB design software do you use?

RE: Help me convert allegro .alg file to Altium .pcbdoc

wolfgangfriedrich — Fri, 05 Jun 2026 13:51:15 GMT

I am taking a guess here, as I don't understand your workflow: you want to use the free Altium viewer.

There are other options:

1) Use the .brd file from the TI project zip file, Allegro has a free viewer too.

2) Install KiCAD 10, it has a very capable Allegro importer and view the file in KiCAD. It is free and does not need a license.

3) Use the Gerber/ODB++ files to analyze the board with one of a the free Gerber/ODB viewers. There are too many to list them all.

RE: Help me convert allegro .alg file to Altium .pcbdoc

abtAmit — Fri, 05 Jun 2026 13:08:13 GMT

I don't have altium licence. So i can't convert it.

I tried to get 15days Free trial but i haven't got any licence from Altium.

RE: Help me convert allegro .alg file to Altium .pcbdoc

wolfgangfriedrich — Fri, 05 Jun 2026 12:29:16 GMT

.alg is not the native Allegro PCB format, it is an intermediate format used for transferring or migrating designs between Allegro and other PCB software.

Altium should be the software to convert this. Normally PCB software companies don't supply exporters to support their competition. It is up to your favourite software of choice to rely on their import capabilities for other formats.

Have you even tried the Altium import wizard? What problems did it have importing the .alg file?

New member working on PCB review workflows

EthanKang — Wed, 20 May 2026 16:28:17 GMT

Hi everyone,

I’m new to posting here, although I’ve been reading element14 on and off for a while. I’m a hardware/software developer, mostly working around board bring-up, PCB review workflows, and the software side of making hardware projects easier to inspect and share.

For the past couple of years I’ve been building PCBAtlas, a PCB review workbench for iPad, iPhone, and Mac. It recently entered a public TestFlight beta.

The basic problem I’m trying to work on is that PCB review often lives in too many places at once: EDA screenshots, Gerber viewers, revision folders, notes, chat threads, and informal checklists. PCBAtlas is an attempt to bring some of that review process into a single workbench — import board/manufacturing data, inspect the layout in 2D, keep revisions together, skim a board summary, and export something that can be shared before fabrication.

It is not meant to replace KiCad, an EDA editor, or a CAM/DFM sign-off flow. It is much more limited than that: a review and communication tool for people who already have PCB data and want to inspect it more conveniently.

KiCad `.kicad_pcb` files are where I’ve spent the most testing time so far, especially 2D inspection, 3D viewing, and project/schematic browsing. The beta also supports manufacturing-side imports such as Gerber and IPC-2581, but real-world files always expose quirks, so I’m especially interested in feedback on format compatibility and odd import behavior.

I’d like to participate here as a normal member, not just drop a product thread and disappear. If anyone here regularly reviews boards and wants to try the beta on a real or non-sensitive project, I’d be grateful for blunt feedback on import issues, unclear reports, missing review information, or anything that feels awkward in the workflow.

TestFlight: testflight.apple.com/.../k37Njgd9

I can share a site link, or a short walkthrough in the replies if useful, but I did not want to make the first post link-heavy.

*Disclosure: I’m the developer of PCBAtlas. I’ll answer questions in this thread and won’t DM anyone or add anyone to a mailing list.*

RE: New member working on PCB review workflows

EthanKang — Thu, 21 May 2026 12:29:20 GMT

**Video walkthrough:** https://youtu.be/rAZ_lP4zfCo

Logic Gate Output Changes When Nearby Relay Activates

eva_402 — Mon, 27 Apr 2026 08:08:51 GMT

Hi,
I’m using a few AND/OR logic gates to generate enable signals before they enter a microcontroller. The logic works normally, but sometimes outputs change briefly when a nearby relay switches.

The relay and logic ICs are on the same board.

Questions:

Is this more likely EMI coupling or supply disturbance?
Should I add more decoupling or flyback suppression first?
On the PCB, is physical separation between relay components and logic ICs usually enough?

RE: Logic Gate Output Changes When Nearby Relay Activates

DAB — Thu, 30 Apr 2026 20:54:14 GMT

Never underestimate the value of metal shielding.

Also, ferrite cores can be very useful in reducing induced spikes.

RE: Logic Gate Output Changes When Nearby Relay Activates

colporteur — Tue, 28 Apr 2026 12:52:28 GMT

I've experienced the interference from relays in digital electronics. The components don't even have to be on the same board. Mostly working with Arduino's and raspberry pi. My fix was to code to simulate key bounce. relay contacts under heavy load do tend to generate emf. Its never seems to be good for the contacts and the surround environment. I can give you empathy but not a practical solution.

RE: Logic Gate Output Changes When Nearby Relay Activates

robogary — Mon, 27 Apr 2026 13:05:21 GMT

Depends. Is the relay switching an inductive load ?

If possible, you could remove the relay's load and cycle to see if that is related to misoperation.

Relay coils should have a flyback diode (or a shottkey double back diode tvs) unless it effects any critical timing. Larger coils should also have RC suppression.

If your relay switches an inductive load like a motor or solenoid, that load should also have suppression. The suppression will also ensure the relay contact life.

RE: Logic Gate Output Changes When Nearby Relay Activates

acdc90 — Mon, 27 Apr 2026 08:21:45 GMT

is the gates powered on 5volts

is the relays on 5v or 12v

does the relay have diode across coil

can we have a circuit ?

Thermal profile methodology for DIY reflow — what I know, what I'm missing

pvit — Mon, 13 Apr 2026 00:22:40 GMT

Hi everyone. I built a compact reflow micro-table for hassle-free PCB assembly at home: [mention:8f821a5acb1c40a599317f20e3b6936a:f7d226abd59f475c9d224a79e3f0ec07]

I'd like to write a general guide on setting up thermal profiles, but I lack the practical experience to make something solid. I'm not talking about production-line requirements — more about "reasonably good" for advanced DIY.

What I know so far as hard constraints:

For RoHS/leaded: TAL no more than 60 seconds. For LTS — I'm not sure.
Ramp rate: 1–2°C/sec (except the start)
Cooling rate: ~4°C/sec; passive air cooling is acceptable (not sure about LTS).

Everything else seems to depend on the specific paste and equipment — recommendations vary widely. The bigger frustration is that datasheets give you a profile to follow but don't explain how much the parameters can actually vary. It's like the difference between a datasheet and a reference manual :)

A colleague with hands-on production experience described this simplified approach to me — I'd be curious whether it holds up in practice:

Ramp linearly at 1–2°C/sec
Wait until paste visibly melts across all components
Turn off immediately and let it cool

I'm keeping the scope to LTS and leaded — RoHS/SAC peak temperatures and tighter process windows are an unnecessary complication for beginners.

Questions

How important is a soaking plateau, and how does it depend on the paste type?
How long can components and the board stay above a given temperature before damage becomes a concern?
Is there a minimum time above liquidus required for proper intermetallic formation?
How critical is cooling rate — does the solidification speed affect joint quality, and what is generally preferable?
and so on...

I'd really appreciate input from people with real PCB assembly experience to help systematize the practical nuances — the goal is to put together beginner-friendly guidance on building reflow profiles from scratch.

I've also tried to document my limited experience with LTS pastes here: github.com/.../soldering_paste.md — feedback on what could be improved there would be much appreciated as well.

RE: Thermal profile methodology for DIY reflow — what I know, what I'm missing

BigG — Thu, 16 Apr 2026 16:53:00 GMT

An idea I had (needs effort to explore practical implications) is to place a layer of densely packed steel wool between the plate and the board to allow for warping and to provide a more even heat distribution. The thermal conductivity of steel wool will certainly be better than air but not as good as a solid metal plate.

RE: How to Position an SMT Stencil at Home

pvit — Wed, 15 Apr 2026 11:06:44 GMT

I just imagine squeegee path and keep pins aside. There are 4 corners. 2 pins required. Usually enough variants to select from.

From my experience, the only real problem is to position SMT stencil with ease and high precision. Everything else is not a big deal.

Also, dry paste (high viscosity) is a bit more convenient, but difference is not fatal.

How to Position an SMT Stencil at Home

pvit — Wed, 15 Apr 2026 06:49:24 GMT

This is a positioning method that wasn't obvious to me until I'd tried a few other approaches. Sharing it in case it saves someone time.

The basic idea: use needles and fiducial holes to fix the stencil and PCB to a silicone mat. It's far more accurate and practical than building a makeshift frame with tape.

Use case

- Hobby use — assembling a few boards occasionally
- Open source projects where reproducibility matters (many people will build it)

What's out there

SMT stencil printers (full-size) — large, require dedicated space. Fine for production runs, overkill at home. Also needs a larger stencil, which drives up cost and shipping.
Compact stencil printers — appeared only recently. Much better suited for hobby use. Still somewhat large — might make sense for a dozen boards, but overkill for 1–2.
Fiducial hole positioning — has its nuances, but nearly ideal for hobby use. Unbeatable on price.

Hobby boards typically don't exceed 100×100 mm. In that case a steel stencil runs about $3. The question "solder by hand or use paste?" pretty much answers itself.

Worth noting: in "proper" stencil use the stencil doesn't touch the board — it snaps off during squeegee travel. With fiducial positioning the stencil lies directly on the board. In theory that's worse, but the results are good enough not to worry about.

How to do it

"Use needles and fiducial holes" sounds simple. In practice there are subtleties — needles come in different diameters, and repeatability matters.

For a long time I used AWG 22 steel wire with 0.7 mm holes:

Total offset no more than 0.1 mm
Sufficient for 0.5 mm pitch components

Downsides:

Still need to source the wire
Wire deforms when clipped, so zero clearance is impossible

On recent boards I tried something different. It turns out there are "location pins" at 1 mm diameter and smaller. At one well-known three-letter Chinese fab you can order them for pennies along with the boards. As shown in the photo, each location area has 4 holes — 0.6, 0.65, 1.0, and 1.05 mm — for 0.6 and 1.0 mm pins.

I went with 1.0 mm pins. Very happy with the results:

Pins drop straight into the board — no pushing into the mat
Zero play
Prints are even more precise. Multiple squeegee passes don't smear anything
Result does not depend on user experience

It's too early to call it 100% reproducible, but I've ordered boards this way three times with no issues. For extra safety you could add 1.05 mm holes next to the 1.0 mm ones, but I've never needed them.

If you know other convenient methods — share them.

RE: How to Position an SMT Stencil at Home

BigG — Wed, 15 Apr 2026 10:02:39 GMT

Good idea. I'm just wondering whether these pins will impinge on the solder application process. You typically apply solder paste on the stencil and then scrape across with a card etc.

RE: How to Position an SMT Stencil at Home

Andrew J — Wed, 15 Apr 2026 09:32:16 GMT

I just tape the PCB down to a board along as much of all 4 edges as possible so that it doesn’t move. With the stencil, I place a long piece of tape along one side. The stencil is positioned on the PCB so it is properly aligned then the stencil’s tape is pressed down onto the board (not PCB) and that allows the stencil to (a) not move whilst scraping paste across it; and (b) provides a hinge for lifting it off without disturbing paste. It also allows the stencil to be lowered back down if you’ve missed some paste or could do with more on some pads. Never had an issue with this approach.

RE: Thermal profile methodology for DIY reflow — what I know, what I'm missing

pvit — Mon, 13 Apr 2026 18:51:33 GMT

Yeah. Thin plate => bad heat distribution. Fat plate => slow cooling. I use Pi5 fan to blow from the bottom. It improves cooling speed 2x-3x until melting point reached. But that's still 1°C/sec. Something more serious will not fit device size.

The cheat is to end profile graph on melting point instead of room temp, lol :).

RE: Thermal profile methodology for DIY reflow — what I know, what I'm missing

wolfgangfriedrich — Mon, 13 Apr 2026 17:19:58 GMT

[quote userid="121623" url="~/products/pcbprototyping/f/forum/56848/thermal-profile-methodology-for-diy-reflow-what-i-know-what-i-m-missing/234961"]Using a hotplate like this is very much affected by the heat transfer between plate and board. It is necessary to press the board down on the hotplate since it will almost certainly warp as it heats up.[/quote]

This is probably the most important point to make a hot-plate work, at least when frying larger boards.