KiCadRoutingTools: Skill for Claude Code

Find High-Speed Nets

When this skill is invoked with a KiCad PCB file, perform a comprehensive analysis to identify which nets carry high-speed signals and recommend appropriate signal integrity measures.

Step 1: Load and Extract Components

from kicad_parser import parse_kicad_pcb
pcb = parse_kicad_pcb('path/to/file.kicad_pcb')

# Basic stats
print(f'Total nets: {len(pcb.nets)}')
print(f'Total footprints: {len(pcb.footprints)}')

Also run list_nets.py to get differential pairs and power nets (these inform the analysis):

python3 py_router/list_nets.py path/to/file.kicad_pcb --diff-pairs --power

Note: Differential pairs are handled separately by route_diff.py, which adds its own GND return vias automatically. This analysis focuses on single-ended signal vias from route.py.

Step 2: Pre-Classify Nets by Name Patterns

Scan all net names (case-insensitive) to get an initial speed estimate before datasheet lookup:

speed_tiers = {
    'ultra_high': {  # >1 GHz
        'patterns': ['DDR3', 'DDR4', 'DDR5', 'LPDDR', 'PCIE', 'SATA',
                     'USB3', 'SGMII', 'XGMII', 'TMDS', '10G'],
        'typical_freq_mhz': 1600,
        'typical_rise_ns': 0.3,
    },
    'high': {  # 100 MHz - 1 GHz
        'patterns': ['DDR', 'DQ', 'DQS', 'DQM', 'RGMII', 'RMII',
                     'QSPI', 'QIO', 'SDIO', 'LVDS', 'HDMI',
                     'USB', 'ETH', 'ULPI', 'EMMC'],
        'typical_freq_mhz': 200,
        'typical_rise_ns': 1.0,
    },
    'medium': {  # 10 - 100 MHz
        'patterns': ['SPI', 'SCK', 'SCLK', 'MOSI', 'MISO',
                     'CLK', 'MCLK', 'BCLK', 'JTAG', 'TCK',
                     'TDI', 'TDO', 'TMS', 'SWDIO', 'SWCLK',
                     'CAN', 'SDMMC'],
        'typical_freq_mhz': 50,
        'typical_rise_ns': 3.0,
    },
    'low': {  # <10 MHz
        'patterns': ['I2C', 'SCL', 'SDA', 'UART', 'TX', 'RX',
                     'GPIO', 'LED', 'BTN', 'SW_', 'ADC', 'DAC',
                     'PWM', 'RST', 'RESET', 'EN', 'ENABLE',
                     'IRQ', 'INT'],
        'typical_freq_mhz': 1,
        'typical_rise_ns': 10.0,
    },
}

# Build initial classification
net_speed = {}  # {net_name: (tier, interface_guess, freq_mhz)}
for net in pcb.nets.values():
    if not net.name or net.name == '':
        continue
    name_upper = net.name.upper()
    for tier, info in speed_tiers.items():
        if any(pat in name_upper for pat in info['patterns']):
            net_speed[net.name] = (tier, 'name_match', info['typical_freq_mhz'])
            break