Resolving Address Collisions on Multi Sensor Circuit Boards
Resolve multi-sensor address collisions using pin-strapped dividers, digital multiplexers, or active translators sized against bus capacitance and firmware costs.
Signal Propagation Delay
Transmission Metric
Electrical timing parameters describe the time required for a signal edge to travel across a transmission medium from transmitter to receiver. High-speed board designers measure signal propagation delay to ensure setup and hold times meet digital logic specifications. Physical trace characteristics and substrate dielectric properties govern velocity coefficients along circuit board signal paths.
Scope of this metric covers electrical interconnects, high-speed cables and integrated circuit interconnect traces.
Dielectric Permittivity
Relative dielectric constant values of substrate materials directly dictate phase velocity along printed conductor traces. Variations in substrate glass weave cause local changes in signal propagation delay across differential signal pairs. Electromagnetic wave velocity decreases in direct proportion to the square root of substrate effective relative permittivity.
Embedded stripline geometries exhibit slower propagation speeds than microstrip lines exposed to air on surface board layers. Precise impedance matching routines account for velocity factors to avoid signal reflections along high-speed traces. Trace length formulas incorporate dielectric frequency dispersion to preserve signal timing at microwave frequencies.
Length Matching
Meander routing techniques equalize physical trace lengths to synchronize arrival times across parallel bus lines. Uncompensated signal propagation delay introduces skew, reducing data eye openings in gigabit communication interfaces. Timing margin analysis tools evaluate signal delay skew across worst-case operating condition corners.
Temperature Drift
Thermal expansion and dielectric constant thermal coefficients alter signal speed during operational heating. Critical clock paths require propagation delay compensation across full operating temperature ranges.