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1:20 AM
Folks, what’s a good strategy if I want to match a small motor to a small Lithium battery?
The motor drives a blower. I need to control the speed of the motor within 10%. The entire instrument works one hour a day, and it needs to last for two years. It’s a consumerist product; no a high reliability requirements. The hardware is cost-sensitive.
The battery is a single 18650 Lithium cell, although it isn’t set is stone, and I can specify another battery, if needed. The battery will be recharged by the owner every day.
What would be a good strategy for matching the motor to the battery?
I could get a 6V, or 12V, etc motor, add a boost converter to create a power supply rail for the motor.
I could get a 3V motor and power it with raw battery voltage, drive the motor with PWM, use back-EMF for closed loop control.
 
 
5 hours later…
6:24 AM
@TonyStewartSunnyskyguyEE75 So do you remember that welding question I asked you about the E7018 rods? And nobody seemed to know the answer. Well I figured it out by going to a welding shop and trying out my rods and theirs and measuring everything. It's the voltage. Voltage was the problem for why my rods weren't running.
@TonyStewartSunnyskyguyEE75 Just the voltage, nothing else. Current wasn't the problem, rod type wasn't an issue, rod length wasn't, transformer core saturation wasn't either. It was as simple as voltage.
 
 
2 hours later…
8:13 AM
@ThePhoton That works indeed. I wasn't expecting that even the symbol changes accordingly. So I assumed that there must be a way to place a depletion type component in the first place. Thanks.
 
Tri
8:54 AM
Quick question, in this question - arduino.stackexchange.com/questions/39556/…
Does the person asking the question have SDO on the external ADC connected to MISO on the ATMega32u4? That's my guess but I haven't been able to verify this through the datasheet/googling around
Please @ me so that I get a notification, I don't normally come on here
 
 
9 hours later…
5:25 PM
@Tri Yes, that should be it. (But I only looked quickly at the ADC datasheet and I don't know Arduino at all)
It looks like the required CPHA and CPOL settings might not be the most common ones. And there's some mode set by whether MOSI/SDI is set or not when CS/CNV is asserted.
 
 
3 hours later…
 
1 hour later…
9:55 PM
@Peter For the moment, anyway.
 

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