Voltage and Amperage
- Up to 20s
- 130a continuous
- 220 Max?
Novel/Cool
- NFC Tag turn on for security
- 12v 3a for lights powered by another on/off switch
- On/Off light refers to battery percentage
- Auto Shut Down
- On/Off noise (think Robogotchi style)
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Reliability there is not a AS switch out there that’s available that has the reliability. The only option is a XT90AS
Extra feature
Auto shut off if load is not changing (board been left on un used)
useing the same power button to operate a relay for lights
Integrate a tail light that gets brighter under braking
Power button changing colour depending on Battry discharge state
Super low power consumption in standby mode. Some as switches can kill you battry over several months when off and un used.
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For a second I was thinking “what, how is that related to an AS…” But then I realized:
- People want an integrated 12V buck
- The AS can actually sense when the ESC is charging the battery by sending current back
So yeah, a 12V output that turns on only when braking could be possible and would be amazing! 
Amen. No point in an antispark that you have to disconnect manually anyway on rainy days / months.
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Well, why are the old as switches prone to failure? Was it the inrush current burning out a resistor? How can a new switch be more robust?
I don’t know if any were closely analyzed after failure but there are many ways an electronic switch like that can fail…overvoltage and overcurrent (overtemp) are the two primary paths to failure.
Probably one of more of the MOSFETs used to switch the current on/off.
By not burning out. 
There are a lot of things to consider when selecting components for use in inrush current control. Choosing the right components for the switch’s chosen ratings is critical and often not done correctly.
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Yup, understanding what the chosen MOSFETs can handle and what the level and duration of the inrush current will be is critical. @b264’s post mentions a good way to handle things. Thanks for posting that link here!
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Designing a switch to handle large capacitance ranges, from like 0F to 25mF or more, is a challenge. I’d suggest a digital approach and monitoring the charge level and resistor temperature in real time.
Do power resistors exist with builtin thermistors?
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A perfect AS switch for me would/should have
- roll to start
- anti-thief feature through remote and/or phone
- Remote failure detection
- 5-12v converter for lights,speakers, phone charger, etc
The remote part could be cool you could turn on/off lights or a horn and as soon you approach the board with the remote on it turns on and if the remote disconnect instead of full brakes well it could have some slow braking procedure or a freerolling procedure (user’s choice)
So like a AS switch with a receiver integrated a remote and bluetooth integrated too an add-on maybe?
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Don’t bother with precharge resistor crap.
Just set the slew rate to accomodate worst case that prevents the MOSFETs from burning up.
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8v that flows after a momentary press of the power buttoning (lights on/off). 12v when power flows the other way was my thinking.
This would then work with any esc and remote.
I don’t know if you would need some settings to tune it to the board and how reliable it would be
2nd way could be to use a connection to the motor phase leads same way as some of the older P2S AS switches did then detect when the phase leads switched might be more accurate and responsive bypassing the esc caps.
3rd could be connected the uart or canbus this can still be related because if your integrating the lights in to the power button of the AS to turn on the tail light you also want that same tail light to get brighter under braking.
Brake lights are a huge safety feature informing other riders and vehicles to what you intention is and to avoid collisions
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Are any esk8 ESC’s using input capacitance levels this high? Or are these ebike and other LEV/PEV ESC’s?
I was thinking about the highest case scenario I can think of, with extra headroom on top.
I could picture maybe half that being reached with a powerful 4 motor vehicle with 3mF on each ESC. So I’d feel pretty confident a value like that would cover nearly every use case and some headroom.
Most ESCs I’ve encountered don’t even have quite 3mF, but I don’t know what the future holds.
I also prefer to build with parts that can handle more than what I’m using them for. It can add a large degree of reliability.
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Absolutely!
Thanks for the info. Knowing the values most typically seen let’s me do the usual cost/size vs capability decisions so I always like to dive into the details.
A 25mF capable switch (with an acceptable precharge time) requires a lot more robust setup, more or more expensive MOSFETs, versus a 3mF setup. This might result in two models being created or perhaps even a modular setup where additional MOSFETs can be added.
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VESC 4.12: 1.68mF - 2.04mF each
FOCBOX 1.3: 1.36mF each
VESC 75/300: 2.82mF each
VESC 6, 6+, 6 Mk5: 1.36mF each
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Whoa…thank you!
3mF sounds like a good minimum target.
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That’s each motor, keep in mind.
I’m not sure how much filter capacitance Unity or Stormcore duals have.
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@ducktaperules I like the nfc tag usage and almost put that specifically but imagined myself losing the nfc tag while on a ride and what I would do to circumnavigate that. More phones have nfc writing capability these days too so probably a way to make a specific backup file. Probably easiest to put a sticker on your phone case though.
How cool would it be if you could shove an nfc sticker around a ring or in your glove so the board turned on when you went to grab it?
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NFC sticker inside the cover of your remote 
if you loose that then you got bigger problems.
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Big brain shit right here. I’m over here looking up nfc penis tattoos.
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