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# Machine Kit BLDC Driver: Circuit Development
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![schematic](/images/schematic.png)
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![routing](/images/routed.png)
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The circuit uses a DRV8302 to drive CSD88584 (or CSD88599) half-bridges, which are rated to 40V / 50A and 60V / 30A respectively. Normally, I'll run 24V power. It connects to an AS5147 or AS5047D or AEAT6600 absolute encoder over SPI, and reads phase currents from the amplifier built into the DRV8302, as well as phase voltages from simple voltage dividers (which are clamped to 3V3 with a series of diodes). 

Power is bussed to the board with two M3 Screw Terminals. The board includes room for a 16mm (?) diameter capacitor, and I'll normally use a 1000uF 35V cap here, or as big as I can fit happily.
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## Tackling Noise on the BLDC Driver

OK, this is concerning! I have lots of noise coming through the SPI lines, I'm a bit worried if these are causing errors:

![noise](/images/logic-spi-noise-bldcv05-pwm.png)

This perhaps means I need to run that SPI cable with a differential driver, to be honest this would be dissapointing. 

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## Notes

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 - label lights 
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 - wants one lo-side debug pin!
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 - for resets etc, pull en to gnd on other side of switch!
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 - wants spi debug pins 
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 - wants more gnd pins, for scope, gnd pins to be not beside 3v3
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 - might have to go to DRV8320 - newer, available
  - CSD88548 is CSD88599 but more amps less volts, use these 
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 - use RDT RTD for temp -  223-1563-1-ND
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 - phy RS422 and bring back buck 
 - do 24v fan 40mm on M3 Terminals! silk lands for heatsink 1.1" square

Fan 
 - 1053-1210-ND 
 - 1053-1375-ND