Impedance Controllable Communication Multilayer PCB

  Is high or low impedance better?

The difference between impedance and resistance in PCBA:
1. Different in nature
Impedance: In a circuit with Electronic Resistor and Capacitor, the hindrance to the current in the circuit is called impedance.
Resistor: Resistor is a current-limiting Electronic Components. After the resistor is connected to the circuit, the resistance of the resistor is generally fixed with two pins, which can limit the current through the branch connected to it.
2. Influencing factors
Impedance: in custom pcb fabrication. The ratio of the peak value (or effective value) Um of the voltage across a section of passive circuit in an AC circuit to the peak value (or effective value) Im of the current passing through the circuit is called impedance, which is represented by z and the unit is ohm (Ω). When U is constant, the larger z is, the smaller I is, and the impedance has a limiting effect on the current.
Resistance: The resistance value of this Electronic Components is generally related to temperature, material, length, and cross-sectional area. The physical quantity that measures the resistance affected by temperature is the temperature coefficient, which is defined as the resistance value when the temperature rises by 1°C. The percentage of change.