So here's my first attempt at building a BLHeli_S ESC. The current hardware is made for testing the overall circuit and part choice; the overall goal is a small and lightweight AIO FC.
I'm not sure what the max current will be, but anything above 10 A would be a good start. Battery input: 1 - 3S, maybe 4S.
5V and 3V3 rails are supplied with a TPS630701 buck/boost regulator for 5V and a TPS62823 regulator for 3V3. Those two seem to work.
Schematic:
ESC-0.3-single.pdf <- THIS SCHEMATIC CONTAINS AN ERROR: Ac/Ap, Bc/Bp and Cc/Cp are swapped.
Apparently fixed schematic in
https://www.rcgroups.com/forums/show...6#post43810839
Most parts were chosen for their small size. The NCP81253 gate driver is just 2x2 mm, but needs 5 V logic. There's a level shifter in front, built with a DMN2990UDJ-7 and two resistors. The gate driver drives a SIZ322DT NFET pair.
Here's a screenshot of one channel (and it contains the same error as the first schematic above):
When the gate driver's PWM input is around 2.5 V, it will disable both out FETs.
Here's a logic table for the Ac and Ap signals with their effect on the output:
Code:
Ac Ap PWM PFET NFET
1) 0 1 2V5 off off
2) 1 1 0V off on
3) 0 0 5V on off
4) 1 0 0V off on
The last two columns are labeled PFET and NFET because the level shifter logic makes the whole gate driver look like a pair of PFET and NFET to the MCU. As far as I understand it, O-type firmware should work for this.
Top Layer Silk Screen for
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