Initial Ti375 GNSS IMU board design and documentation
This commit is contained in:
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#!/usr/bin/env python3
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"""Create the placed eight-layer KiCad PCB from the audited design database.
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The script is deterministic so placement, net assignments, stackup, and rules
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can be regenerated and independently audited. Routing uses the staged
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BGA/plane/Freerouting flow in scripts/README.md; finalize_routing.py replaces
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autorouted RF/USB copper with audited deterministic geometry.
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"""
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from __future__ import annotations
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import math
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import re
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import sys
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from collections import defaultdict
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from pathlib import Path
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import pcbnew
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ROOT = Path(__file__).resolve().parents[1]
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sys.path.insert(0, str(ROOT / "scripts"))
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from design_data import components # noqa: E402
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HW = ROOT / "hardware"
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BOARD_FILE = HW / "board.kicad_pcb"
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STOCK = Path("/usr/share/kicad/footprints")
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# The distributed SMT test pads and removal of the former bottom test-point
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# field allow a compact 155 x 90 mm outline.
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X0, Y0, X1, Y1 = 20.0, 20.0, 175.0, 110.0
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def mm(value: float) -> int:
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return pcbnew.FromMM(value)
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def point(x: float, y: float) -> pcbnew.VECTOR2I:
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return pcbnew.VECTOR2I_MM(x, y)
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def footprint_path(identifier: str) -> tuple[Path, str]:
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library, name = identifier.split(":", 1)
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if library == "board":
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return HW / "board.pretty", name
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return STOCK / f"{library}.pretty", name
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MAJOR = {
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# FPGA/configuration. All four PMODs are on the north edge, close to the
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# BGA side carrying their I/O banks. Rotation makes the connector field
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# shallow and keeps all modules clear of the RF and IMU regions.
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"U1": (108, 72, 0), "U26": (97, 54, 0),
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"JPMOD1": (78, 24, 0), "JPMOD2": (96, 24, 0),
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"JPMOD3": (114, 24, 0), "JPMOD4": (132, 24, 0),
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# USB-C and debug block.
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"J1": (23.1, 48, 270), "U5": (30.5, 44.5, 0), "U6": (30.5, 51.5, 0),
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"U2": (43, 55, 0), "U25": (35, 62, 0), "U3": (51, 63, 0),
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"U29": (60, 54.5, 0), "U30": (67, 58.5, 0), "U31": (62, 63.5, 0),
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# Mechanically quiet IMU region.
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"U22": (51, 84, 0),
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# Protected input and switching-power block.
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"J3": (24, 100, 90), "U7": (34, 96, 0), "U8": (42, 104, 0), "U9": (46, 96, 0),
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"U10": (54, 104, 0), "U11": (59, 104, 0), "U12": (64, 94, 0),
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# High-current FPGA rails sit directly south of the BGA. This keeps the
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# 15-A core path and both 6-A I/O-rail paths short enough to enter their
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# local plane patches without long high-current traces.
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"U13": (100, 93, 0), "U14": (115, 97, 0), "U15": (130, 97, 0), "U16": (90, 98, 0),
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"U17": (143, 63, 0), "U18": (136, 67, 0), "U19": (152, 67, 0), "U20": (163, 63, 0),
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"U28": (141, 72.5, 0), "U32": (136, 74.5, 0), "U34": (88, 88, 0),
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"Q1": (70, 62, 0),
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# User reset controls remain edge-accessible; only the tiny protection and
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# open-drain circuitry sit inward from the connector/button.
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"J4": (73, 106.5, 180), "SW1": (82, 106, 0), "D2": (78, 100.5, 0),
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"U33": (87, 103, 0),
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# RF front end. J2's launch reference is exactly on the right PCB edge.
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"J2": (175, 42, 0), "D1": (170.45, 40.75, 0), "FL1": (164.0, 42.1, 180),
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"J5": (171, 56, 0), "U27": (165, 52, 0), "U21": (155.5, 45, 0),
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"U23": (149, 53, 0), "U24": (137, 55, 0),
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}
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# Parts whose exact physical location materially affects signal integrity,
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# power-loop area, or mechanical performance.
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SPECIAL = {
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# RF series parts are collinear. L4 pad 2 lands directly on the SMA feed
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# rather than creating a bias-tee stub; the optional shunt-tuning pad 1s
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# likewise land on the two controlled-impedance sections.
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"C83": (167.5, 42.1, 180), "C84": (162.15, 41.45, 90), "R39": (160.5, 42.1, 180),
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"C85": (159.0, 40.70, 90), "L4": (169.5, 42.585, 90),
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"L1": (105.0, 91.0, 0), "L2": (115.0, 91.0, 0), "L3": (130.0, 91.0, 0),
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"FB1": (60.0, 88.5, 0), "FB2": (36.0, 49.0, 0), "FB3": (39.0, 46.5, 0),
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"R63": (37.0, 55.50, 0), "R64": (37.0, 54.50, 0),
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# MAX2771 output damping sits at the receiver; FPGA-driven 3-wire control
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# damping sits at the BGA source. R55 holds SHDN low at the receiver.
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"R45": (151.0, 44.5, 0),
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"R46": (154.6, 50.2, 90), "R47": (155.8, 50.2, 90),
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"R48": (157.0, 50.2, 90), "R49": (158.2, 50.2, 90),
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"R50": (160.5, 47.5, 90),
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"R51": (121.5, 65.5, 0), "R52": (121.5, 66.7, 0),
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"R53": (121.5, 67.9, 0), "R54": (121.5, 69.1, 0),
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"R55": (161.7, 44.5, 90), "C89": (146.5, 53.0, 0),
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# 40-MHz termination is at U24. SafeSPI controller outputs are terminated
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# beside the FPGA; MISO and EXTRESN bias remain beside the IMU.
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"R56": (140.2, 54.35, 0),
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"R57": (102.0, 58.8, 0), "R58": (104.0, 58.8, 0),
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"R59": (106.0, 58.8, 0), "R60": (60.0, 83.6, 0),
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"R61": (41.0, 83.6, 0),
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# Buffered FTDI interface-1 hard JTAG. Output-series parts sit directly
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# after the power-domain buffer; the TDO part is retained at the FPGA side.
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"R70": (65.0, 52.0, 0), "R71": (65.0, 53.2, 0),
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"R72": (65.0, 54.4, 0), "R73": (96.0, 70.0, 0),
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"R74": (96.0, 71.2, 0),
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}
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# Small SMT bring-up pads live beside the circuit they measure; there is no
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# connector-like test-point bank along the board edge.
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SPECIAL.update({
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"TP1": (37.5, 94.0, 0), "TP2": (45.5, 104.0, 0),
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"TP3": (166.5, 54.0, 0), "TP4": (29.0, 39.0, 0),
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"TP5": (22.0, 89.0, 0), "TP6": (49.5, 98.5, 0),
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"TP7": (66.5, 90.0, 0), "TP8": (105.0, 98.0, 0),
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"TP9": (118.0, 102.0, 0), "TP10": (133.0, 102.0, 0),
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"TP11": (146.0, 61.0, 0), "TP12": (137.0, 70.0, 0),
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"TP13": (97.0, 58.0, 0), "TP14": (99.0, 58.0, 0),
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"TP15": (91.5, 103.0, 0),
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# Added configuration/JTAG pulls and reset-domain support.
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"R89": (96.0, 65.0, 0),
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"R90": (96.0, 66.2, 0), "R91": (96.0, 67.4, 0), "R92": (96.0, 68.6, 0),
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"R93": (96.0, 72.4, 0), "R94": (96.0, 73.6, 0),
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"R95": (96.0, 74.8, 0), "R96": (96.0, 76.0, 0),
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"R97": (59.0, 65.5, 0), "R98": (145.0, 74.5, 0),
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"R99": (73.0, 60.0, 0), "R100": (73.0, 61.2, 0), "R101": (73.0, 62.4, 0),
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"R102": (84.0, 100.5, 0), "R103": (80.0, 102.0, 0),
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"C120": (145.0, 72.5, 0), "C121": (82.0, 102.0, 0),
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"C122": (142.0, 76.5, 0), "C123": (64.0, 48.5, 0),
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"C124": (69.5, 56.0, 0), "C125": (62.0, 66.5, 0),
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"C126": (136.0, 78.0, 0), "C127": (90.0, 100.5, 0),
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"R104": (83.0, 86.8, 0), "R105": (83.0, 88.0, 0),
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"R106": (83.0, 89.2, 0), "C128": (93.0, 88.0, 0),
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})
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# Critical placement references must never silently drift when parts are added
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# earlier in design_data.py. A mismatch here would corrupt RF geometry or put
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# a source-series resistor at the receiver end of a long digital trace.
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CRITICAL_REF_NETS = {
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"C83": {"RF_SMA", "RF_PRE_SAW"},
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"C84": {"RF_POST_SAW", "GND"},
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"R39": {"RF_POST_SAW", "MAX_MIXIN_HI"},
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"C85": {"MAX_MIXIN_HI", "GND"},
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"R56": {"OSC40_OUT", "CLK_40M_FPGA"},
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"R57": {"IMU_SCK", "IMU_SCK_DEV"},
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"R58": {"IMU_MOSI", "IMU_MOSI_DEV"},
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"R59": {"IMU_CS", "IMU_CS_DEV"},
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"R60": {"IMU_MISO", "IMU_MISO_DEV"},
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}
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_component_by_ref = {component.ref: component for component in components}
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for _ref, _expected_nets in CRITICAL_REF_NETS.items():
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_actual_nets = {pin.net for pin in _component_by_ref[_ref].pins if pin.net}
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assert _actual_nets == _expected_nets, (_ref, _actual_nets, _expected_nets)
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def local_offsets(count: int, clearance_radius: float) -> list[tuple[float, float]]:
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"""Return dense candidate rings for collision-aware group placement."""
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result: list[tuple[float, float]] = []
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ring = 0
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while len(result) < count:
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r = clearance_radius + ring * 1.20
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slots = max(12, int(2 * math.pi * r / 0.80))
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for idx in range(slots):
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angle = -math.pi / 2 + idx * 2 * math.pi / slots
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result.append((r * math.cos(angle), r * math.sin(angle)))
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if len(result) == count:
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return result
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ring += 1
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return result
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def courtyard_box(fp: pcbnew.FOOTPRINT, margin: float = 0.12) -> tuple[float, float, float, float]:
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layers = pcbnew.LSET()
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layers.AddLayer(pcbnew.F_CrtYd)
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layers.AddLayer(pcbnew.B_CrtYd)
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box = fp.GetLayerBoundingBox(layers)
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return (pcbnew.ToMM(box.GetX()) - margin, pcbnew.ToMM(box.GetY()) - margin,
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pcbnew.ToMM(box.GetRight()) + margin, pcbnew.ToMM(box.GetBottom()) + margin)
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def boxes_overlap(a: tuple[float, float, float, float], b: tuple[float, float, float, float]) -> bool:
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return a[0] < b[2] and a[2] > b[0] and a[1] < b[3] and a[3] > b[1]
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def add_text(board: pcbnew.BOARD, value: str, x: float, y: float, size: float = 1.0,
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layer: int = pcbnew.F_SilkS, angle: float = 0) -> None:
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text = pcbnew.PCB_TEXT(board)
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text.SetText(value)
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text.SetPosition(point(x, y))
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text.SetTextSize(pcbnew.VECTOR2I(mm(size), mm(size)))
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text.SetTextThickness(mm(max(0.15, size * 0.15)))
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text.SetLayer(layer)
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text.SetTextAngle(pcbnew.EDA_ANGLE(angle, pcbnew.DEGREES_T))
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board.Add(text)
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def add_outline(board: pcbnew.BOARD) -> None:
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for start, end in (((X0, Y0), (X1, Y0)), ((X1, Y0), (X1, Y1)),
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((X1, Y1), (X0, Y1)), ((X0, Y1), (X0, Y0))):
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seg = pcbnew.PCB_SHAPE(board)
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seg.SetShape(pcbnew.SHAPE_T_SEGMENT)
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seg.SetStart(point(*start))
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seg.SetEnd(point(*end))
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seg.SetWidth(mm(0.05))
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seg.SetLayer(pcbnew.Edge_Cuts)
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board.Add(seg)
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def configure_rules(board: pcbnew.BOARD) -> None:
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ds = board.GetDesignSettings()
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ds.SetBoardThickness(mm(1.6))
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ds.m_TrackMinWidth = mm(0.10)
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ds.m_MinClearance = mm(0.10)
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ds.m_ViasMinSize = mm(0.45)
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ds.m_MinThroughDrill = mm(0.225)
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ds.m_ViasMinAnnularWidth = mm(0.10)
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ds.m_CopperEdgeClearance = mm(0.25)
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ds.m_HoleClearance = mm(0.19)
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settings = ds.m_NetSettings
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default = settings.GetDefaultNetclass()
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default.SetClearance(mm(0.10))
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default.SetTrackWidth(mm(0.12))
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default.SetViaDiameter(mm(0.45))
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default.SetViaDrill(mm(0.225))
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default.SetDiffPairWidth(mm(0.135))
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default.SetDiffPairGap(mm(0.15))
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def netclass(name: str, clearance: float, width: float, via: float = 0.45, drill: float = 0.225,
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diff_width: float | None = None, diff_gap: float | None = None) -> None:
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nc = pcbnew.NETCLASS(name)
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nc.SetClearance(mm(clearance))
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nc.SetTrackWidth(mm(width))
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nc.SetViaDiameter(mm(via))
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nc.SetViaDrill(mm(drill))
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if diff_width is not None:
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nc.SetDiffPairWidth(mm(diff_width))
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if diff_gap is not None:
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nc.SetDiffPairGap(mm(diff_gap))
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settings.SetNetclass(name, nc)
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netclass("BGA_ESCAPE", 0.10, 0.10)
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netclass("RF50_CPWG", 0.20, 0.164)
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netclass("USB90_DIFF", 0.15, 0.135, diff_width=0.135, diff_gap=0.15)
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netclass("CLOCK", 0.15, 0.15)
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# A 0.45/0.225-mm dogbone via with 0.10-mm clearance fits the Ti375's
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# 0.8-mm BGA pitch. The 0.40-mm trunk width is retained; Freerouting's
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# automatic neck-down is allowed only inside the escape field.
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netclass("POWER", 0.10, 0.40, 0.45, 0.225)
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for pattern in ("RF_SMA", "RF_PRE_SAW", "RF_POST_SAW", "MAX_MIXIN_HI"):
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settings.SetNetclassPatternAssignment(pattern, "RF50_CPWG")
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for pattern in ("USB_D_P", "USB_D_N", "FTDI_D_P", "FTDI_D_N"):
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settings.SetNetclassPatternAssignment(pattern, "USB90_DIFF")
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# Use exact clock families so VCC3V0_CLK does not acquire an accidental
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# aggregate CLOCK,POWER effective class.
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for pattern in ("MAX_CLKOUT*", "MAX_SCLK*", "MAX_ADC_CLKIN", "QSPI_SCLK",
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"CLK_40M_FPGA", "OSC40_OUT", "TCXO16_OUT", "FTDI_OSC12",
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"FTDI_OSCI", "IMU_SCK*", "*TCK*"):
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settings.SetNetclassPatternAssignment(pattern, "CLOCK")
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for pattern in ("VCC*", "SYS5", "VBUS_RAW", "USB5_PROT", "EXT5_*", "GND", "CORE_SW",
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"BUCK1V8_SW", "BUCK3V3_SW", "ANT_BIAS_SEL", "ANT_BIAS_SW",
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"FTDI_1V8", "FTDI_VPHY", "FTDI_VPLL", "IMU_3V3",
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"IMU_VREGA2", "IMU_VREGD", "USB_SHIELD"):
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settings.SetNetclassPatternAssignment(pattern, "POWER")
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settings.SetNetclassPatternAssignment("EXP_*", "BGA_ESCAPE")
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settings.SetNetclassPatternAssignment("PMOD*", "BGA_ESCAPE")
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def add_stackup(board: pcbnew.BOARD) -> None:
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board.SetCopperLayerCount(8)
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board.SetLayerName(pcbnew.In1_Cu, "L2_GND")
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board.SetLayerName(pcbnew.In2_Cu, "L3_SIG")
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board.SetLayerName(pcbnew.In3_Cu, "L4_PWR")
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board.SetLayerName(pcbnew.In4_Cu, "L5_SIG")
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board.SetLayerName(pcbnew.In5_Cu, "L6_SIG")
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board.SetLayerName(pcbnew.In6_Cu, "L7_GND")
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board.SetLayerType(pcbnew.In1_Cu, pcbnew.LT_POWER)
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board.SetLayerType(pcbnew.In3_Cu, pcbnew.LT_POWER)
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board.SetLayerType(pcbnew.In6_Cu, pcbnew.LT_POWER)
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def place_components(board: pcbnew.BOARD) -> dict[str, pcbnew.FOOTPRINT]:
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net_items: dict[str, pcbnew.NETINFO_ITEM] = {}
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for comp in components:
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for pin in comp.pins:
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if pin.net and pin.net not in net_items:
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item = pcbnew.NETINFO_ITEM(board, pin.net)
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board.Add(item)
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net_items[pin.net] = item
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loaded: dict[str, pcbnew.FOOTPRINT] = {}
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current_group = "U1"
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groups: dict[str, list] = defaultdict(list)
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for comp in components:
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if comp.ref in MAJOR:
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current_group = comp.ref
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if comp.ref not in MAJOR and comp.ref not in SPECIAL:
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if comp.description.startswith("Ti375 ") or "Efinix mandatory" in comp.description:
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groups["U1"].append(comp)
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else:
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groups[current_group].append(comp)
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group_positions: dict[str, list[tuple[float, float]]] = {}
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for group, members in groups.items():
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radius = 4.0
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if group == "U1":
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radius = 11.5
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elif group in {"U2", "U13", "U21", "U22"}:
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radius = 5.5
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# Extra candidates let the actual courtyard collision pass skip places
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# occupied by adjacent functional blocks and larger bulk capacitors.
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group_positions[group] = local_offsets(max(1000, len(members) * 40), radius)
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automatic: list[tuple[object, str]] = []
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current_group = "U1"
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for comp in components:
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path, name = footprint_path(comp.footprint)
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fp = pcbnew.FootprintLoad(str(path), name)
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||||
if fp is None:
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||||
raise RuntimeError(f"Cannot load {comp.footprint} for {comp.ref}")
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fp.SetReference(comp.ref)
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||||
fp.SetValue(comp.value)
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||||
fp.Reference().SetVisible(False)
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||||
fp.Value().SetVisible(False)
|
||||
fp.Reference().SetLayer(pcbnew.F_Fab)
|
||||
fp.Value().SetLayer(pcbnew.F_Fab)
|
||||
# Dense components retain complete assembly/Fab graphics, while the
|
||||
# production silkscreen is limited to functional labels and the IMU
|
||||
# orientation mark so it cannot print on fine-pitch copper.
|
||||
for graphic in fp.GraphicalItems():
|
||||
if graphic.GetLayer() == pcbnew.F_SilkS:
|
||||
graphic.SetLayer(pcbnew.F_Fab)
|
||||
if comp.ref in MAJOR:
|
||||
current_group = comp.ref
|
||||
x, y, rotation = MAJOR[comp.ref]
|
||||
elif comp.ref in SPECIAL:
|
||||
x, y, rotation = SPECIAL[comp.ref]
|
||||
else:
|
||||
group = "U1" if (comp.description.startswith("Ti375 ") or "Efinix mandatory" in comp.description) else current_group
|
||||
ax, ay, _ = MAJOR[group]
|
||||
x, y, rotation = ax, ay, 0
|
||||
automatic.append((comp, group))
|
||||
fp.SetPosition(point(x, y))
|
||||
fp.SetOrientationDegrees(rotation)
|
||||
if comp.dnp:
|
||||
fp.SetDNP(True)
|
||||
fp.SetExcludedFromPosFiles(True)
|
||||
fp.SetField("MPN", comp.mpn)
|
||||
fp.SetField("Manufacturer", comp.manufacturer)
|
||||
for field_name in ("MPN", "Manufacturer"):
|
||||
field = fp.GetField(field_name)
|
||||
field.SetVisible(False)
|
||||
field.SetLayer(pcbnew.F_Fab)
|
||||
board.Add(fp)
|
||||
loaded[comp.ref] = fp
|
||||
|
||||
pad_map: dict[str, list[pcbnew.PAD]] = defaultdict(list)
|
||||
for physical_pad in fp.Pads():
|
||||
if physical_pad.GetNumber():
|
||||
pad_map[physical_pad.GetNumber()].append(physical_pad)
|
||||
for pin in comp.pins:
|
||||
for physical_pad in pad_map[str(pin.number)]:
|
||||
if pin.net:
|
||||
physical_pad.SetNet(net_items[pin.net])
|
||||
|
||||
# Place all automatic local parts after the fixed functional floorplan is
|
||||
# known, using their actual KiCad courtyards rather than nominal body size.
|
||||
occupied = [courtyard_box(loaded[ref]) for ref in (*MAJOR.keys(), *SPECIAL.keys()) if ref in loaded]
|
||||
search_start: dict[str, int] = defaultdict(int)
|
||||
for comp, group in automatic:
|
||||
fp = loaded[comp.ref]
|
||||
ax, ay, _ = MAJOR[group]
|
||||
candidates = group_positions[group]
|
||||
placed = False
|
||||
for idx in range(search_start[group], len(candidates)):
|
||||
dx, dy = candidates[idx]
|
||||
x, y = ax + dx, ay + dy
|
||||
fp.SetPosition(point(x, y))
|
||||
candidate = courtyard_box(fp)
|
||||
# Keep assembly courtyards on-board; edge connectors are all fixed
|
||||
# members and are intentionally permitted to protrude.
|
||||
if candidate[0] < X0 + 0.5 or candidate[2] > X1 - 0.5 or candidate[1] < Y0 + 0.5 or candidate[3] > Y1 - 0.5:
|
||||
continue
|
||||
if any(boxes_overlap(candidate, used) for used in occupied):
|
||||
continue
|
||||
occupied.append(candidate)
|
||||
search_start[group] = idx + 1
|
||||
placed = True
|
||||
break
|
||||
if not placed:
|
||||
raise RuntimeError(f"Could not place {comp.ref} near {group} without courtyard overlap")
|
||||
board.BuildListOfNets()
|
||||
return loaded
|
||||
|
||||
|
||||
def add_mounting_holes(board: pcbnew.BOARD) -> None:
|
||||
path = STOCK / "MountingHole.pretty"
|
||||
# The lower-left power connector owns the corner; offset H3 so its screw
|
||||
# head and courtyard cannot collide with J3.
|
||||
for idx, (x, y) in enumerate(((24, 24), (171, 24), (31, 106), (171, 106)), 1):
|
||||
fp = pcbnew.FootprintLoad(str(path), "MountingHole_3.2mm_M3")
|
||||
if fp is None:
|
||||
raise RuntimeError("Missing KiCad M3 mounting-hole footprint")
|
||||
fp.SetReference(f"H{idx}")
|
||||
fp.Reference().SetVisible(False)
|
||||
fp.SetPosition(point(x, y))
|
||||
board.Add(fp)
|
||||
|
||||
|
||||
def add_zone(board: pcbnew.BOARD, net_name: str, layer: int,
|
||||
bounds: tuple[float, float, float, float], priority: int = 0) -> None:
|
||||
"""Add a retained solid inner-layer plane region.
|
||||
|
||||
These regions are retained even before fanout vias exist so the Specctra
|
||||
export contains real plane targets for the router. The final refill then
|
||||
clears anti-pads around every unrelated via and plated hole.
|
||||
"""
|
||||
net = board.FindNet(net_name)
|
||||
if net is None:
|
||||
raise RuntimeError(f"Cannot create plane for missing net {net_name}")
|
||||
x0, y0, x1, y1 = bounds
|
||||
zone = pcbnew.ZONE(board)
|
||||
zone.SetLayer(layer)
|
||||
zone.SetNet(net)
|
||||
zone.SetLocalClearance(mm(0.20))
|
||||
zone.SetMinThickness(mm(0.10))
|
||||
zone.SetThermalReliefGap(mm(0.20))
|
||||
zone.SetThermalReliefSpokeWidth(mm(0.25))
|
||||
zone.SetPadConnection(pcbnew.ZONE_CONNECTION_FULL)
|
||||
zone.SetIslandRemovalMode(pcbnew.ISLAND_REMOVAL_MODE_NEVER)
|
||||
zone.SetAssignedPriority(priority)
|
||||
outline = zone.Outline()
|
||||
outline.NewOutline()
|
||||
for x, y in ((x0, y0), (x1, y0), (x1, y1), (x0, y1)):
|
||||
outline.Append(point(x, y))
|
||||
board.Add(zone)
|
||||
|
||||
|
||||
def add_power_planes(board: pcbnew.BOARD) -> None:
|
||||
# Continuous reference planes immediately below the two outer signal
|
||||
# layers. A 0.50-mm inset exceeds JLCPCB's copper-to-edge requirement.
|
||||
for layer in (pcbnew.In1_Cu, pcbnew.In6_Cu):
|
||||
add_zone(board, "GND", layer, (X0 + 0.50, Y0 + 0.50, X1 - 0.50, Y1 - 0.50))
|
||||
|
||||
# L4 is a deliberately split DC plane. Islands follow the functional
|
||||
# floorplan; no high-speed route uses L4 and no signal crosses a split on
|
||||
# either adjacent routing layer without a nearby return transition.
|
||||
islands = (
|
||||
("VCC3V3_AUX", (20.50, 38.00, 67.00, 72.00)),
|
||||
("VCC3V3", (39.00, 73.00, 68.00, 85.10)),
|
||||
("SYS5", (20.50, 85.50, 90.00, 109.50)),
|
||||
("SYS5", (90.40, 106.40, 140.00, 109.50)),
|
||||
# Core balls are interspersed with GND/auxiliary balls, so a complete
|
||||
# local patch (with automatic anti-pads) replaces the invalid left/right
|
||||
# voltage split that previously crossed the BGA field.
|
||||
("VCC0V95", (95.00, 60.50, 119.00, 94.00)),
|
||||
("VCC3V3", (119.50, 87.00, 140.00, 106.00)),
|
||||
("VCC3V0_CLK", (126.00, 50.00, 148.50, 72.00)),
|
||||
("VCC3V0_DIG", (119.50, 60.50, 125.50, 72.00)),
|
||||
("VCC3V0_DIG", (148.90, 50.40, 164.00, 72.00)),
|
||||
("VCC3V3_ANT", (164.40, 50.40, 174.50, 70.00)),
|
||||
("VCC3V0_RF", (145.00, 36.00, 174.50, 50.00)),
|
||||
)
|
||||
for priority, (net_name, bounds) in enumerate(islands, 1):
|
||||
add_zone(board, net_name, pcbnew.In3_Cu, bounds, priority)
|
||||
|
||||
# Local BGA supply patches. L2/L7 remain uninterrupted ground planes;
|
||||
# only the area below and immediately south of U1 is reserved on these
|
||||
# otherwise routable signal layers.
|
||||
add_zone(board, "VCC1V8", pcbnew.In4_Cu, (97.50, 60.50, 122.00, 101.00), 50)
|
||||
add_zone(board, "VCC3V3", pcbnew.In5_Cu, (97.50, 60.50, 140.00, 101.00), 50)
|
||||
|
||||
|
||||
def add_temporary_critical_keepouts(board: pcbnew.BOARD) -> None:
|
||||
"""Reserve the layers below RF and USB while Freerouting is running.
|
||||
|
||||
F.Cu deliberately remains available so the autorouted critical nets reserve
|
||||
their own top-layer corridors. The rule areas prevent unrelated signal
|
||||
tracks and through vias from crossing underneath. finalize_routing.py
|
||||
removes these temporary areas before installing the audited copper.
|
||||
"""
|
||||
layers = pcbnew.LSET()
|
||||
for layer in (pcbnew.In2_Cu, pcbnew.In4_Cu, pcbnew.In5_Cu, pcbnew.B_Cu):
|
||||
layers.AddLayer(layer)
|
||||
for name, bounds in (
|
||||
("TEMP_RF_NO_DIGITAL_BELOW", (152.0, 36.0, 174.5, 49.5)),
|
||||
("TEMP_USB_NO_CROSSING_BELOW", (22.0, 41.5, 44.5, 57.5))):
|
||||
x0, y0, x1, y1 = bounds
|
||||
area = pcbnew.ZONE(board)
|
||||
area.SetZoneName(name)
|
||||
area.SetIsRuleArea(True)
|
||||
area.SetLayerSet(layers)
|
||||
area.SetDoNotAllowTracks(True)
|
||||
area.SetDoNotAllowVias(True)
|
||||
area.SetDoNotAllowPads(False)
|
||||
area.SetDoNotAllowFootprints(False)
|
||||
area.SetDoNotAllowZoneFills(False)
|
||||
outline = area.Outline()
|
||||
outline.NewOutline()
|
||||
for x, y in ((x0, y0), (x1, y0), (x1, y1), (x0, y1)):
|
||||
outline.Append(point(x, y))
|
||||
board.Add(area)
|
||||
|
||||
|
||||
def add_documentation_graphics(board: pcbnew.BOARD) -> None:
|
||||
add_text(board, "Ti375 GNSS / SCH16T", 105, 33.0, 1.1)
|
||||
add_text(board, "REV A1 JLC08161H-3313 8L", 105, 35.2, 0.8)
|
||||
add_text(board, "USB-C 5V", 31, 35.5, 0.9)
|
||||
add_text(board, "EXT_5V", 28, 108.0, 0.9)
|
||||
add_text(board, "GPS L1/L1C ACTIVE", 162, 34, 0.9)
|
||||
add_text(board, "BIAS J5: 3V3-OFF-5V", 163, 72, 0.8)
|
||||
add_text(board, "RF - NO DIGITAL ROUTING BELOW", 151, 69, 0.8)
|
||||
add_text(board, "IMU PIN1", 42, 78, 0.8)
|
||||
add_text(board, "X+ -> Y+ ^", 51, 84, 0.8)
|
||||
add_text(board, "USB JTAG / UART", 55, 38.5, 0.8)
|
||||
add_text(board, "EXT_RST", 73, 101.5, 0.8)
|
||||
add_text(board, "FPGA RESET", 82, 109.0, 0.8)
|
||||
add_text(board, "PMOD1 3V3", 78, 30, 0.8)
|
||||
add_text(board, "PMOD2 3V3", 96, 30, 0.8)
|
||||
add_text(board, "PMOD3 1V8", 114, 30, 0.8)
|
||||
add_text(board, "PMOD4 1V8", 132, 30, 0.8)
|
||||
|
||||
|
||||
STACKUP = '''\t\t(stackup
|
||||
\t\t\t(layer "F.SilkS" (type "Top Silk Screen"))
|
||||
\t\t\t(layer "F.Paste" (type "Top Solder Paste"))
|
||||
\t\t\t(layer "F.Mask" (type "Top Solder Mask") (thickness 0.01))
|
||||
\t\t\t(layer "F.Cu" (type "copper") (thickness 0.035))
|
||||
\t\t\t(layer "dielectric 1" (type "prepreg") (thickness 0.0994) (material "JLC 3313") (epsilon_r 4.1) (loss_tangent 0.02))
|
||||
\t\t\t(layer "L2_GND" (type "copper") (thickness 0.0152))
|
||||
\t\t\t(layer "dielectric 2" (type "core") (thickness 0.1) (material "JLC FR-4 core") (epsilon_r 4.36) (loss_tangent 0.02))
|
||||
\t\t\t(layer "L3_SIG" (type "copper") (thickness 0.0152))
|
||||
\t\t\t(layer "dielectric 3" (type "prepreg") (thickness 0.3568) (material "JLC 3x2116") (epsilon_r 4.16) (loss_tangent 0.02))
|
||||
\t\t\t(layer "L4_PWR" (type "copper") (thickness 0.0152))
|
||||
\t\t\t(layer "dielectric 4" (type "core") (thickness 0.3) (material "JLC FR-4 core") (epsilon_r 4.41) (loss_tangent 0.02))
|
||||
\t\t\t(layer "L5_SIG" (type "copper") (thickness 0.0152))
|
||||
\t\t\t(layer "dielectric 5" (type "prepreg") (thickness 0.3568) (material "JLC 3x2116") (epsilon_r 4.16) (loss_tangent 0.02))
|
||||
\t\t\t(layer "L6_SIG" (type "copper") (thickness 0.0152))
|
||||
\t\t\t(layer "dielectric 6" (type "core") (thickness 0.1) (material "JLC FR-4 core") (epsilon_r 4.36) (loss_tangent 0.02))
|
||||
\t\t\t(layer "L7_GND" (type "copper") (thickness 0.0152))
|
||||
\t\t\t(layer "dielectric 7" (type "prepreg") (thickness 0.0994) (material "JLC 3313") (epsilon_r 4.1) (loss_tangent 0.02))
|
||||
\t\t\t(layer "B.Cu" (type "copper") (thickness 0.035))
|
||||
\t\t\t(layer "B.Mask" (type "Bottom Solder Mask") (thickness 0.01))
|
||||
\t\t\t(layer "B.Paste" (type "Bottom Solder Paste"))
|
||||
\t\t\t(layer "B.SilkS" (type "Bottom Silk Screen"))
|
||||
\t\t\t(copper_finish "ENIG")
|
||||
\t\t\t(dielectric_constraints yes)
|
||||
\t\t)'''
|
||||
|
||||
|
||||
def inject_stackup(path: Path) -> None:
|
||||
data = path.read_text()
|
||||
if "\n\t\t(stackup\n" in data:
|
||||
data = re.sub(r"\n\t\t\(stackup\n.*?\n\t\t\)\n", "\n" + STACKUP + "\n", data, count=1, flags=re.S)
|
||||
else:
|
||||
data = data.replace("\n\t(setup\n", "\n\t(setup\n" + STACKUP + "\n", 1)
|
||||
data = data.replace("(allow_soldermask_bridges_in_footprints no)",
|
||||
"(allow_soldermask_bridges_in_footprints yes)")
|
||||
path.write_text(data)
|
||||
|
||||
|
||||
def main() -> None:
|
||||
board = pcbnew.BOARD()
|
||||
add_stackup(board)
|
||||
configure_rules(board)
|
||||
add_outline(board)
|
||||
loaded = place_components(board)
|
||||
add_mounting_holes(board)
|
||||
add_power_planes(board)
|
||||
add_temporary_critical_keepouts(board)
|
||||
add_documentation_graphics(board)
|
||||
title = board.GetTitleBlock()
|
||||
title.SetTitle("Ti375 C529 GPS L1/L1C + SCH16T acquisition board")
|
||||
title.SetRevision("A0")
|
||||
title.SetCompany("JLCPCB manufacturing design")
|
||||
title.SetComment(0, "USB-C 5 V primary; protected EXT_5V; no back-feed")
|
||||
title.SetComment(1, "JLC08161H-3313 exact eight-layer construction")
|
||||
if not pcbnew.ZONE_FILLER(board).Fill(board.Zones()):
|
||||
raise RuntimeError("Initial inner-plane fill failed")
|
||||
pcbnew.SaveBoard(str(BOARD_FILE), board)
|
||||
inject_stackup(BOARD_FILE)
|
||||
print(f"Placed {len(loaded)} schematic components plus four NPTH mounting holes")
|
||||
print(f"Saved {BOARD_FILE}")
|
||||
|
||||
|
||||
if __name__ == "__main__":
|
||||
main()
|
||||
Reference in New Issue
Block a user