imrishabh18/nema-23-stepper-controller

engineering/pd-controller-redesign.json

{
  "revision": "F",
  "version": "1.3.0-local",
  "oldPart": {
    "mpn": "CH224Q",
    "jlcpcb": "C46061833",
    "package": "DFN-10, 2x2mm, 0.4mm pitch"
  },
  "newPart": {
    "mpn": "CH224A",
    "jlcpcb": "C42459160",
    "package": "ESSOP-10, 4.9x3.9mm body, 1.0mm pitch, exposed ground pad",
    "stockObserved": 17855,
    "stockDateLocal": "2026-10-07",
    "inventoryReserved": false
  },
  "primaryDatasheet": "https://www.wch-ic.com/downloads/CH224DS1_PDF.html",
  "datasheetPdf": "https://datasheet.lcsc.com/datasheet/pdf/4f12eebccb4eda2c0038806df0155265.pdf?productCode=C970725",
  "retainedFunctions": [
    "5/9/12/15/20/28V requests",
    "28V EPR with a real rated cable",
    "210kohm 28V startup configuration",
    "7-bit I2C address 0x22 or 0x23",
    "registers 0x09, 0x0A, 0x50",
    "active-low open-drain PG",
    "internal CFG2/CFG3 pull-ups and separate logic-side I2C buffer"
  ],
  "changedPlacements": {
    "U_PD": {
      "x": 3.8,
      "y": 16.3,
      "rotation": 90
    },
    "C_PD": {
      "x": -2,
      "y": 15,
      "rotation": 180
    },
    "R_PD_CFG": {
      "x": 1.2,
      "y": 19.8
    },
    "R_PD_PG": {
      "x": -0.5,
      "y": 21.5
    },
    "C_EF_IN": {
      "x": 10,
      "y": 8.5
    },
    "U_EFUSE": {
      "x": 13,
      "y": 12.5,
      "rotation": 270
    }
  },
  "efuseNotes": "C2864391 exact supplier import replaces RGER lands; IN1/IN2 and OUT1/OUT2 labels follow the new import while physical pin connectivity is preserved. Manual path transforms account for the new footprint rotation. The wide feed was moved to clear the longer supplier lands.",
  "assemblyValidation": "Raw supplier CAD and converter import snapshots, all numbered IC pads, orientation baselines and exported PnP checked. Existing unrelated assembly/mechanical/DFM holds remain.",
  "publication": "Local only; do not use published v1.2.7 fabrication files for this redesign."
}