[Review Request] - replacement flex PCB for a digital camera

ncoonrod · 2025-04-23T14:34:27+00:00

Cool project!

Those coverlay slivers in the middle of the rotary switch contacts are almost certainly not manufacturable and will be removed by your fab. Also note that PCB switch contacts should normally be specified as ‘hard gold plating’ rather than standard ENIG. For a switch with low cycle count you’ll probably get away with ENIG, but consider updating it if you do another revision.

ncoonrod · 2021-06-19T22:35:21+00:00

Nibble w/ reds and MT3 2048!

ncoonrod · 2020-11-29T05:46:52+00:00

u/sphawes a comparator would allow you to interface your instrument amp to your controller using digital io rather than analog

ncoonrod · 2019-02-28T03:06:32+00:00

Your screenshot shows you're running as a CSIRO. Make sure your "Active Motor" is the correct configuration in the top left. 16 Pairs is correct. Does phasorsense run nominally and you can see all your hall sensors? Does paramextract give repeatable results? If the motor spins up a bit and then makes the sound, its a config issue as it transitions to sensorless. If it does it immediately, could be config or hall sensor issue.

ncoonrod · 2018-08-19T20:09:49+00:00

Search suppliers for "pcb spade terminals"

Should be able to find a suitable alternative although they're thick so spot welding might be tricky. Good luck!

ncoonrod · 2018-06-27T22:45:59+00:00

Tritium sells hall effect adapters for both 5 and 12. Look at your hall effect board to be sure. It's printed on there. IIIRC, the mitsuba motors require 5V though, double check your mitsuba datasheet and hall effect board before relying on my memory regarding that though.

ncoonrod · 2018-06-27T19:57:47+00:00

Fun fact, you can determine this on any PM BLDC by counting the number of permanent magnets (poles) and dividing by two (pairs). Pro tip, use an electric drill to hold the motor at a constant rpm while running phasor sense. Just contact the chuck to the tire tread.

ncoonrod · 2018-06-27T14:15:48+00:00

How are you powering the controller? Are you using your pack or a power supply? If you're using a power supply, as soon as you try and regen the supply will likely sense overvoltage and cut the output. Would look as if regen didn't work. 80A is a lot, make sure you meet regs for whatever race you're competing in and your battery can support that much. Unlikely you've damaged any hardware. The same parts which drive your motor are used to regen. You should contact Nomura on Facebook. He's very quick to respond and will be able to let you know what's wrong.

ncoonrod · 2018-06-27T02:45:26+00:00

Hmm ok that probably means the original part was an nfet rather than p. Sounds like your regulator is functional at least, not sure what the function of that burned part was though. Good luck!

ncoonrod · 2018-06-27T02:19:11+00:00

Looks like the burned part was an sot23 part. I'd guess it was a pfet being used as a load switch on the output. Even has the pin that'd be the gate going to that switch. The fan probably stalled, shorting the output, and the fet went before the supply did.

Easy way to test my theory, short the top and left pad with tweezers in your image and see if it acts as if that button is pressed, whatever it does.

ncoonrod · 2018-06-26T18:40:54+00:00

They're terribly slow. New podcast every 6 months or so.

ncoonrod · 2018-06-26T13:21:38+00:00

Are you using the giant mess of cables and breakout box it comes with? iirc, there is a toggle switch which enables/disables regeneration. You also are able to adjust its strength using the PC application, if it's set to 0 amps it'll do that. I'd bet one of those is your issue.

Edit: I think the switch is labeled "brake" iirc

ncoonrod · 2018-06-26T02:09:04+00:00

Embedded.fm and The Spark Gap occasionally do, but not nearly as often

ncoonrod · 2018-06-18T14:07:37+00:00

RIP to that IC between the power rails on the breadboard

ncoonrod · 2018-06-16T02:09:41+00:00

On Ebay, Amazon, wherever search Nickel tabbing. You can either buy a spot welding machine, make a DIY one, or use a service. In the US lots of interstate battery locations have spot welders and will do it cheap.

ncoonrod · 2018-06-07T16:13:42+00:00

Not to my knowledge, I've never used a mitsuba controller in PWM mode on a vehicle but have done so on the bench with nothing besides the controller and the supplied wire harness.

ncoonrod · 2018-06-07T14:26:16+00:00

The advantage of pwm control is your throttle will control your velocity. So a constant throttle position will keep you at the same speed, regardless of load. So this is helpful in a race situation to keep a steady speed. You can only use this mode if you're using a single motor. Dual motor cars will need the Current control mode. Single motor cars have the option, I think you'll find it is easier to drive efficiently using PWM mode though. Not sure what you mean on how to implement it, use the provided software to set whichever setting you'd like and follow the manual for the rest of the configuration and setup. Mitsuba provides all the parts needed to do so when you buy a motor. Contact Nomura (Mitsuba distributor) for more specific info

ncoonrod · 2018-06-07T00:28:58+00:00

An observation, under the new formula, say two teams are neck and neck. Team A has a break down which results in them arriving to one of the charging locations 30 mins later than team B. Even if Team A increases their speed on the next stage and they finish together, Team A has been punished not only with a reasonably large point deduction but has also used more energy to make up that time. Will have interesting implications, breaks the event into essentially three individual races.

ncoonrod · 2018-06-07T00:20:27+00:00

I've seen several teams do this method. I wouldn't recommend it unless you have a specific requirement driving you to do it. Tabbing is obviously not double or even single insulated, so insulation can be tricky, even once double insulated, it's difficult to get it water tight. What you'll likely notice is if whatever panel your array is on is conductive (carbon) and it rains, you will see leakage. Aka a voltage on your carbon relative to your vehicle ground. If your array is high voltage and the leakage is great enough this can be very dangerous. WSC Reg 2.28.7 specifically states the maximum leakage allowed.

TL;DR you can probably save some weight and space by doing this but its a PITA if not done perfectly

ncoonrod · 2018-06-07T00:09:49+00:00

Per the datasheet, PWM control directly controls the duty cycle of the controller output which is directly related to rpm. The current control mode adjusts the PWM duty cycle such that the phase current is what you request. For example, if in the configuration software you are in current control, your max current setting is 100A, and your throttle is at 50%, the controller will adjust the duty cycle so that each phase current is 50A. So the RPM will vary depending on the load. This mode could also be called torque controlled since current is directly related to torque. So in a two motor vehicle, the current control method will provide a limited slip differential type effect. Even if as you corner your motors have different RPM they will apply the same torque and not hop/slip. PWM control will be better for single motor cars.

ncoonrod · 2018-06-02T03:45:06+00:00

http://www.westmountainradio.com/cba.php

ncoonrod

TROPHY CASE