Remove the L7805 linear regulator (12V→5V) and its input/output caps,
replacing it with a TPS61088 boost converter circuit (5V→12V) for the
A4988 stepper driver. The ESP32 is now powered directly from the 5V
input rail. Includes integration script and project sym-lib-table for
the custom TPS61088 symbol library.
Python generator script produces a KiCad 9 schematic for the TPS61088
boost converter circuit (5V input, 12V/2A output) with feedback divider,
compensation network, bootstrap cap, and input/output filtering.
Includes a nix flake for the build environment.
Extend board outline downward by 15mm to accommodate 6 new components:
U1 (L7805 voltage regulator), C1/C2/C3 (decoupling caps), R1/R2 (pull-down
resistors). Move bottom mounting holes to match new outline. Delete
incorrectly-routed traces for DIR, STEP, LIM_C and unconnected nets, then
re-route them correctly to ESP32 bottom-row pins. Add +5V and +12V power
traces on B.Cu with via for layer transition. Route MOTOR_CTRL on B.Cu to
avoid F.Cu conflicts.
Place U1, C1, C2, C3, R1, R2 in the left open area (x=73-86, y=48-60)
of the board outline. Add copper traces for +12V bus (U1 input to
existing +12V net via A4988), +5V bus (U1 output to ESP32 VIN and C2),
and limit switch signals (/LIM_A to SW1, /LIM_C to existing trace).
Remove orphaned net-0 segments and clear zone fills for regeneration.
- Move regulator section labels (U1, C1, C2) to non-overlapping positions
- Hide redundant A4988 value text and R1/R2 GND value text
- Shift +3.3V, +12V, and GND power labels for better spacing
- Move C3, R1, R2 reference/value text away from nearby labels
- Add LM7805 (TO-220) with input/output caps to step 12V→5V for ESP32 VIN
- Add 10K pull-down resistors on D5/LIM_A and D4/LIM_C limit switch GPIOs
- Add 100uF electrolytic decoupling capacitor on A4988 VMOT
- Rewire A4988 ~ENABLE from GND to ESP32 D18 via MOTOR_EN net label
Remove all 60 point-to-point wires and 11 junctions. Replace with:
- 13 local power symbols (+3.3V, +12V, GND) at each power pin
- 10 net labels (STEP, DIR, LIM_A, LIM_C, MOTOR_CTRL) for signals
- 37 short stub wires connecting pins to labels/power symbols
- 4 direct wires for A4988 motor outputs to stepper connector
Electrical connectivity is preserved. No component positions changed.
Shift all 30 pins uniformly by +5.765mm to place bottom pins at
Y=37.2, exactly 5.8mm from the silkscreen bottom line. Adjust
silkscreen, fab, and courtyard bottom edges to Y=43/43.1. Pins
maintain their relative 2.54mm spacing.
Stretch bottom boundary from Y=37.235 to Y=43.92 so the footprint
spans 51mm from antenna top to USB-C end. Update silkscreen,
courtyard, and fab outlines accordingly. Also fix broken right-side
silkscreen line endpoint.
Move pin columns from 22.86mm to 25.4mm X spacing. Shift all pins
up by 4.125mm so bottom pins sit 5.8mm from the footprint bottom
boundary. Update silkscreen, courtyard, and fab outlines to match.
0xWheatyz
