What is Inductance?
The property of a trace that opposes the change of current flowing through it and even a straight trace will have some inductance.
Inductors do this by generating self-induced electromagnetic fields (EMF) within themselves as a result of their changing the magnetic field. In an electrical circuit, when the emf is induced in the same circuit in which the current is changing this effect is called Self-induction, ( L ) but it is sometimes commonly called back-EMF as its polarity is in the opposite direction to the applied voltage.
When the EMF is induced into an adjacent component situated within the same magnetic field, the emf is said to be induced by Mutual-induction, ( M ) and mutual induction is the basic operating principal of MEMS (micro-electromechanical system), used in airbag deployment, insulin pumps, and building ventilation systems. Self-inductance is a special case of mutual inductance, and because it is produced within a single isolated circuit we generally call self-inductance simply, Inductance.
The basic unit of measurement for inductance is called the Henry, ( H ) after Joseph Henry, but it also has the units of Webers per Ampere ( 1 H = 1 Wb/A ).
The sample PCB shown in figure 3 has three coils. Figure 4 shows one coil as a generator and two sensor coils.
Why Gardien’s Solution?
Gardien has implemented a simplified, and flexible solution into our G-Serries Flying Probe machines and fixture-based machines. Gardien designed the process for ease of use on our service floors, allowing accuracy and reduced training (virtually push-button technology).
Parameters that can be adjusted to meet the PCB build requirements:
- Resistance within fixed tolerance
- Inductance within fixed tolerance
All information from the PCB fabrication drawing is transferred in the Tooling process via UCAMCO software to the job specific files. The information is then output into the file that is used to perform the measurement.