Pickle Hub PH-1 · rev B

The board.

One 66 × 44 mm, two-layer PCB runs the whole kit: an ESP32-C3 with Bluetooth and Wi-Fi, USB-C charging, a buck-boost supply, a 24-bit load-cell front end, two photogate comparators and the encoder port. All 68 SMT parts are JLCPCB basic or extended; DRC passes with zero violations.

Gerbers (JLCPCB)BOMCPLSchematic PDFKiCad project (.zip)

Loading 3D model…
3D from the rev B placement · photo textured66 × 44 × 1.6 mm FR-4Drag to rotate · scroll to zoom
As built

Rev B, assembled by JLCPCB.

Photographed before the first flash. Firmware 1.2 is now running on it and advertising over Bluetooth.

Top: ESP32-C3-WROOM-02 (upper left), BOOT and RESET, USB-C and power switch along the bottom edge, LC and ENC headers on the right, PG1 and PG2 along the bottom.
Top: ESP32-C3-WROOM-02 (upper left), BOOT and RESET, USB-C and power switch along the bottom edge, LC and ENC headers on the right, PG1 and PG2 along the bottom.
Bottom: ground pour, test points, battery polarity mark and the open-hardware label.
Bottom: ground pour, test points, battery polarity mark and the open-hardware label.
Top copper and silkscreen
Bottom copper
Architecture

Five blocks, one bus.

USB-C 5 VUSBLC6 ESD · CC 5.1 k LiPo 3.7 V · 2000 mAhJST-PH · 35 × 60 × 7 pouch TP4056 charger235 mA · CHG / FULL LEDs TPS63001 buck-boost3.3 V from 1.8–5.5 V ESP32-C3-WROOM-02BLE 5 · Wi-Fi · USB CDCBOOT · RESET · BLE LED HX711 · 24-bitload cell · 80 SPS · 3V3A AS5600 encoderI²C · 5-pin ENC header LM393 ×2photogates PG1 / PG2 · 1 µs Battery ADCVBAT/2 on IO3
ESP32-C3RISC-V 160 MHz · 4 MB · BLE 5 + Wi-Fi
68SMT parts · 38 BOM lines
0 / 0DRC violations / unconnected
74 / 74circuit checks pass (ngspice)
Connectors

Everything plugs in. Nothing is soldered at home.

Right-angle 2.54 mm headers on two edges; one Dupont ribbon pack wires the whole kit.

HeaderPinsGoes to
ENC3V3 · GND · SCL · SDA · DIRAS5600 module in the cart or the spindle flange
LC3V3A · A+ · A− · GND (R G W B)20 kg bar load cell on the cart nose or the hanging hook
PG1 / PG23V3 · SIG · LED · GNDPhotogate forks
BATJST-PH 2-pin2000 mAh pouch under the board
USB-C5 V · D+ · D−Charging, flashing, wired dashboard
GPIOFunctionNote
IO0 / IO1SDA / SCLI²C 400 kHz
IO2HX_RATE80 SPS default
IO3VBAT_ADCbattery divider
IO4 / IO5HX_DOUT / HX_SCK24-bit force
IO6 / IO7PG1 / PG2ISR-timestamped
IO8BLE LEDactive low
IO9BOOTzero / tare
IO18 / IO19USBnative CDC
Verified before fab

Simulated, then measured.

ngspice runs on the hand-over, battery range, comparator and reset paths; every IC pinout read back against its datasheet.

USB unplug at 3.7 V, 150 mA — the rail holds
USB unplug at 3.7 V, 150 mA — the rail holds
Battery-only: 3.3 V regulated down to 2.8 V
Battery-only: 3.3 V regulated down to 2.8 V
Photogate comparator with hysteresis
Photogate comparator with hysteresis
Power-on EN ramp and a RESET press
Power-on EN ramp and a RESET press

Boards for builders.

Order it yourself from the Gerbers, or buy the assembled board with the kit.

Buy the kitOr build it yourself — free files