💬 Easy/Newbie PCB for MySensors
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After several hours of debugging and changing all possible components, i built exactly same circuit on prototype board and with exactly same (active) components I was able to go down to 1.9, sometimes to 1.8, while on the easyboard only down to 2.6. I also used exactly the same booster on both prototype and on the easyboard.
But then a breakthrough, I have found one passive component that was different between the two mentioned boards! It was the radio freaking capacitor, on the "good" board it was 47uf, and on the problematic board had 4.7uf!
I changed radio cap to 47uf and I am now able to go on both boards down to 2.3v. Which is ok, not the 1.9v but it is good enough (for now :) ) So those 42.3uf were missing for radio to go ~0.5v lower in voltage I guess.The one thing I am missing on the prototyping board is the voltage measurement circuit, so I guess that gives some 0.4v lowest threshold or something, i will test these days on the prototyping board, just to verify.
Thank you @sundberg84 for attention and help :)
Are you able to provide 1.9v on battery input on some easy board with the dht22? Like the one from the photos on the openhardware?
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both boards are now identical, they go down to 2.3, but I will put 2.4 in scripts as the minimum, just to be sure.
If a board boots at 2.4 it can go down til 2.2 and maybe 2.1, and it will work, but cannot reboot at that voltage.@dakipro - 2.4 volts will last you a long time.
If you want to go further I would suggest you look at the advanced user section of the EasyPCB and remove the booster and lower BOD instead. This will not work with the DHT22 but you could change that to BME280 and the radio @ 1.9v will be your lowest point. Either that or go for a more expensive booster. Im accually trying this in another project (https://www.sparkfun.com/products/10967) so I can give some feedback in a near future.
Im also building a variable power supply which might help me to try different volt levels on my boards as well... all I need now is a oscilloscope - anyone wants to fund (and teach) me :) ?
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@dakipro - 2.4 volts will last you a long time.
If you want to go further I would suggest you look at the advanced user section of the EasyPCB and remove the booster and lower BOD instead. This will not work with the DHT22 but you could change that to BME280 and the radio @ 1.9v will be your lowest point. Either that or go for a more expensive booster. Im accually trying this in another project (https://www.sparkfun.com/products/10967) so I can give some feedback in a near future.
Im also building a variable power supply which might help me to try different volt levels on my boards as well... all I need now is a oscilloscope - anyone wants to fund (and teach) me :) ?
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@sundberg84 wow, that's a quite expensive booster :cold_sweat:
@gohan - yes almost 5 times more expensive but I'm building it myself and it's probably five times better...
@dakipro https://www.openhardware.io/view/4/EasyNewbie-PCB-for-MySensors check "Battery without step up booster (advanced users)"
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@sundberg84 wow, that's a quite expensive booster :cold_sweat:
@gohan said in 💬 Easy/Newbie PCB for MySensors:
@sundberg84 wow, that's a quite expensive booster :cold_sweat:
The chip itself is less than 0.7$ on Arrow.com (so, legit one) so with additional components it should be 2$.
But I see in the datasheet that typical operating current for 3.3V version is 45uA, added to the 15% of losses (max 85% efficiency) I'm a bit skeptical about the battery life you can get using it ?
@sundberg84 if you find someone funding oscilloscopes, please send me the contact :D Else you have the captures in the datasheet for the most critical cases :P
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@gohan said in 💬 Easy/Newbie PCB for MySensors:
@sundberg84 wow, that's a quite expensive booster :cold_sweat:
The chip itself is less than 0.7$ on Arrow.com (so, legit one) so with additional components it should be 2$.
But I see in the datasheet that typical operating current for 3.3V version is 45uA, added to the 15% of losses (max 85% efficiency) I'm a bit skeptical about the battery life you can get using it ?
@sundberg84 if you find someone funding oscilloscopes, please send me the contact :D Else you have the captures in the datasheet for the most critical cases :P
@Nca78 45 uA will last me a long time. On my dht nodes I aim for <100uA so if you sleep between readings that's ok. If this circuit would be much better than these cheap eBay boosters I'm happy even if they run at a couple of more uA
Will let you know if I find oscilloscope funder 😉
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@Nca78 45 uA will last me a long time. On my dht nodes I aim for <100uA so if you sleep between readings that's ok. If this circuit would be much better than these cheap eBay boosters I'm happy even if they run at a couple of more uA
Will let you know if I find oscilloscope funder 😉
@sundberg84 said in 💬 Easy/Newbie PCB for MySensors:
@Nca78 45 uA will last me a long time. On my dht nodes I aim for <100uA so if you sleep between readings that's ok. If this circuit would be much better than these cheap eBay boosters I'm happy even if they run at a couple of more uA
Will let you know if I find oscilloscope funder 😉
But I still fail to see the interest of all the pain with the boosters and keeping the DHT22 which need "high" voltage of 3.3V when a sht21/si7021 is 3$ or less on aliexpress and can run way over 1 year with a simple cr2032 ? And if you use 2 AA it will run for 5 years. No problem with noise/stability, no booster to buy, just a 0.x$ big capacitor to add in parallel with the battery if you're using a CR2032 (and nothing if you're using 2 AA/AAA).
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@sundberg84 said in 💬 Easy/Newbie PCB for MySensors:
@Nca78 45 uA will last me a long time. On my dht nodes I aim for <100uA so if you sleep between readings that's ok. If this circuit would be much better than these cheap eBay boosters I'm happy even if they run at a couple of more uA
Will let you know if I find oscilloscope funder 😉
But I still fail to see the interest of all the pain with the boosters and keeping the DHT22 which need "high" voltage of 3.3V when a sht21/si7021 is 3$ or less on aliexpress and can run way over 1 year with a simple cr2032 ? And if you use 2 AA it will run for 5 years. No problem with noise/stability, no booster to buy, just a 0.x$ big capacitor to add in parallel with the battery if you're using a CR2032 (and nothing if you're using 2 AA/AAA).
@Nca78 Another option that I went with is an HDC1080. The only problem with this one is that according to the datasheet, the recommended operating minimum voltage is 2.7v, where the si7021's minimum is 1.9v. When I was looking on ebay, these said that they were a replacement for the si7021, and it was my mistake not checking the datasheet before buying. They do seem to be working good though and I have had one of them running for about 5 months with no trouble so far.
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@sundberg84 said in 💬 Easy/Newbie PCB for MySensors:
@Nca78 45 uA will last me a long time. On my dht nodes I aim for <100uA so if you sleep between readings that's ok. If this circuit would be much better than these cheap eBay boosters I'm happy even if they run at a couple of more uA
Will let you know if I find oscilloscope funder 😉
But I still fail to see the interest of all the pain with the boosters and keeping the DHT22 which need "high" voltage of 3.3V when a sht21/si7021 is 3$ or less on aliexpress and can run way over 1 year with a simple cr2032 ? And if you use 2 AA it will run for 5 years. No problem with noise/stability, no booster to buy, just a 0.x$ big capacitor to add in parallel with the battery if you're using a CR2032 (and nothing if you're using 2 AA/AAA).
@Nca78 that's why I added the option without boosters. The only downside is that it's not that easy changing bod. When you get the booster function to work you can also run a motion dec in 3.3v for example. 3.3v will give you more sensor options.
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@sundberg84 said in 💬 Easy/Newbie PCB for MySensors:
Battery without step up booster (advanced users)
I could just (do it very very ugly) and cut the vcc line near the board and solder it directly to the battery input?
That way both arduino and radio will get battery power, and dht22 would still receive 3.3v? (then I can lower the BOD)
Or would that not work due to some other connection?Also, would flashing pro mini to 1Mhz benefit battery consumption at all? (while still using 3.3 booster)
(p.s. I stole your signature :) )
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@Nca78 that's why I added the option without boosters. The only downside is that it's not that easy changing bod. When you get the booster function to work you can also run a motion dec in 3.3v for example. 3.3v will give you more sensor options.
@sundberg84 That is one of the nice things about your board is it's flexibility.
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@Nca78 that's why I added the option without boosters. The only downside is that it's not that easy changing bod. When you get the booster function to work you can also run a motion dec in 3.3v for example. 3.3v will give you more sensor options.
@sundberg84 said in 💬 Easy/Newbie PCB for MySensors:
@Nca78 that's why I added the option without boosters. The only downside is that it's not that easy changing bod. When you get the booster function to work you can also run a motion dec in 3.3v for example. 3.3v will give you more sensor options.
Well, it is pretty easy IMHO, you just have to follow on of the many tutorials, and you learn a lot on the way :)
For motion detection isn't a booster a bad idea ? You can use AM312 anyway, very small and very stable, no soldering necessary to run it down to 2.7V meaning you can use most of the capacity of a lithum cell like CR123.@dbemowsk thanks for the information I didn't even know about this sensor, looks like a very precise one with a very low power consumption. Can you link to where you bought it from I see nothing below 4$ on aliexpress ?
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@sundberg84 said in 💬 Easy/Newbie PCB for MySensors:
@Nca78 45 uA will last me a long time. On my dht nodes I aim for <100uA so if you sleep between readings that's ok. If this circuit would be much better than these cheap eBay boosters I'm happy even if they run at a couple of more uA
Will let you know if I find oscilloscope funder 😉
But I still fail to see the interest of all the pain with the boosters and keeping the DHT22 which need "high" voltage of 3.3V when a sht21/si7021 is 3$ or less on aliexpress and can run way over 1 year with a simple cr2032 ? And if you use 2 AA it will run for 5 years. No problem with noise/stability, no booster to buy, just a 0.x$ big capacitor to add in parallel with the battery if you're using a CR2032 (and nothing if you're using 2 AA/AAA).
@Nca78 said in 💬 Easy/Newbie PCB for MySensors:
when a sht21/si7021 is 3$ or less on aliexpress
The thing is that when people start with mysensors and arduinos, none of these are listed on Store page, so using them would be experimenting basically. And experimenting before you have even begun anything is a bit masochistic. At least in my case that is how I was thinking, so I ordered several of dht22, not really knowing that there are better/efficient alternatives. Maybe we can get those sensors in the store page, perhaps mention them on the examples page, noting that they are more efficient?
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I went for the BME280, a little expensive, but it uses I2C and can be run from 1.71 volt to 3.3 volt.
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@sundberg84 said in 💬 Easy/Newbie PCB for MySensors:
@Nca78 that's why I added the option without boosters. The only downside is that it's not that easy changing bod. When you get the booster function to work you can also run a motion dec in 3.3v for example. 3.3v will give you more sensor options.
Well, it is pretty easy IMHO, you just have to follow on of the many tutorials, and you learn a lot on the way :)
For motion detection isn't a booster a bad idea ? You can use AM312 anyway, very small and very stable, no soldering necessary to run it down to 2.7V meaning you can use most of the capacity of a lithum cell like CR123.@dbemowsk thanks for the information I didn't even know about this sensor, looks like a very precise one with a very low power consumption. Can you link to where you bought it from I see nothing below 4$ on aliexpress ?
@Nca78 I believe this is the same one that I bought, at least the carrier board looks to be labeled the same. Mine was just listed as an HDC1080, where this one is listed as a GY-213V-HDC1080. I am assuming it is the same chip. When I bought the 2 that I have I paid $5/module shipped which after looking at this one was a bit high. Live and learn though.
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@Nca78 said in 💬 Easy/Newbie PCB for MySensors:
when a sht21/si7021 is 3$ or less on aliexpress
The thing is that when people start with mysensors and arduinos, none of these are listed on Store page, so using them would be experimenting basically. And experimenting before you have even begun anything is a bit masochistic. At least in my case that is how I was thinking, so I ordered several of dht22, not really knowing that there are better/efficient alternatives. Maybe we can get those sensors in the store page, perhaps mention them on the examples page, noting that they are more efficient?
@dakipro the dht22 is a hot potato not only due to 3.3 req but also quality... I know this has been requested for removal on homepage before and I think it's just a matter of someone makes a good example for another sensor to replace it with.
Yes you can cut the trace for vcc and hardwire it from bat if you want to lower bod.
And yes it's not that hard to lower bod... but harder than booster and therefore I choose the easiest option since that's my board goal.
I'm running 1mhz with booster and motion without problems... but same there, with a bad booster it will false trigger.
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This might be the better example you are looking for https://github.com/mysensors/MySensorsArduinoExamples/pull/25
@mfalkvidd so all we need is some graphics and some text 👍?