Regenerative Braking Design Discussion

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The generator inputs, bridge rectifiers, TVS clamp, supercapacitor equivalent, bleeder, and protected bus are wired; I’m wiring the charger, battery, and load rails next.

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Created the full schematic for the regenerative braking charger and renamed the project to Regenerative Braking Charger. I added/wired the motor inputs, dual bridge rectifiers, TVS clamp, supercapacitor equivalent, BQ25750 charger stage with external MOSFETs, 2S battery connector/protection, 5 V rail, 3.3 V RC522 rail, LCD/MCU/RFID connectors, and support passives.
Open items:
  • BQ25750 bootstrap/compensation/feedback values still need datasheet-final tuning before layout.
  • Supercapacitor bank is represented as an equivalent C1; final cell count, balancing, fuse, ESR, and discharge timing need sizing.
  • I2C is pulled to 3.3 V for IC safety; add level shifting if your LCD module forces 5 V I2C pull-ups.
Suggested next steps:
  1. Finalize BQ25750 component values from the TI datasheet.
  2. Size the supercapacitor bank from expected braking energy.
  3. Move to PCB layout/placement after those values are locked.
  4. Use the new Board Bring-Up Plan for first-power validation.
Finalize charger and layout
Finalize BQ25750 values
Size supercapacitor bank
Add safety protections
Proceed to placement
  • Generic Inductor
    Generic Inductor
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  • Generic Capacitor
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    1.5M
  • Generic Resistor
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    1.5M
  • Ground
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    20.5M
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    Terminal
    An electrical connector acting as reusable interface to a conductor and creating a point where external circuits can be connected.
    natarius
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    Wirelessly connects nets on schematic. Used to organize schematics and separate functional blocks. To wirelessly connect net portals, give them same designator. #portal
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  • RMCF0805JT47K0
    RMCF0805JT47K0
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    1.2M
  • 875105359001
    875105359001
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    CTL1206FYW1T
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    1.1M
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    1070TR
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Regenerative Braking Charger thumbnail
Regenerative braking power generation and charging circuit using two DC motor generators, rectification, TVS protection, supercapacitor buffering, a 2S Li-ion buck-boost charger, BMS protection, and regulated 5 V/3.3 V load rails.

Properties

Properties describe core aspects of the project.

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