Address Collisions When Four Parts Share One I2C Bus
Resolve four-part I2C address collisions using 4-state pin strapping, quad-channel switches, or address translation ICs based on BOM cost and driver complexity.
Pass-Gate Multiplexer
Switch Topology
Transmission gate switches select and route multiple analog sensor channels to a shared analog-to-digital converter using complementary metal-oxide-semiconductor transistors. Mixed-signal readout integrated circuits employ a pass-gate multiplexer to reduce component count and power consumption in multi-channel sensor interface boards. The switching network governs channel-to-channel isolation, signal linearity and switching settling time.
Operational boundaries are set by input signal voltage limits that must remain within the power supply rails to prevent parasitic latch-up.
On-Resistance Distortion
Transistor channel resistance varies non-linearly with input signal voltage levels. Non-linear resistance in a pass-gate multiplexer introduces harmonic distortion into high-precision sensor measurements. Complementary transistor pairs balance channel resistance across the full input voltage range to minimize total harmonic distortion.
Charge Injection
Control gate voltage transitions transfer unwanted charge into the signal path through parasitic gate-to-drain capacitance. Parasitic charge injection within a pass-gate multiplexer creates voltage step offsets on high-impedance sample-and-hold capacitors. Differential switching architectures and dummy transistor gates absorb injected charge to preserve measurement precision.
Routing Bandwidth
Channel switching speed dictates maximum sampling rates in multi-sensor acquisition systems. Precision testing measures pass-gate multiplexer crosstalk isolation by applying full-scale sinusoidal signals to adjacent inactive channels. Dynamic response limits are verified using automated semiconductor parameter analyzers.