Electrical Test Probe Overview

Test probesIn the hardware implementation of an embedded system the most important thing is to check various points in the integrated circuits. Examples of these points are voltage, current, resistance, capacitance, frequency, etc. Measurements instruments are available to offer such services, but the equipment cannot be connected to the circuits directly. Electrical test probes are used for the connection between measurement equipment and circuit under test. The probe respective to specific test equipment is attached to the equipment. It can be handheld and provides required measurement when touched to a specific point or points.

Electrical Test probe Types

The most common electrical test probes used in embedded system hardware designs and circuit testing include current probes, voltage probes, high voltage probes, oscilloscope probes, high frequency probes, differential and single ended probes, logic probes, optical probes, magnetic probes, polarity probes, continuity probes, semi conductor probes, coaxial probes, and test probes. Differential and single ended probes operate in pairs. A differential probe measures the signal at point with reference to other probe's point. Whereas single ended probe measures with respect to ground. Logic probes are used in digital circuit design and testing. Polarity probe gives the polarity of the circuit (positive or negative) automatically simply by attaching to the device or circuit. Semi conductor interconnects are accessed through semiconductors probes. Semiconductor probes are spring loaded and mounted into test jig.

Electrical test probe physical specifications

Physical specifications of an electrical test probe refer to the probe's physical structure. Bent metal, chip configuration, and alligator clip are the common styles for electrical test probes.

Bent metal

Bent metal probes as their name contains bent metal contacts to connect to specific point or points on the device or circuit under test. These probes are like sticks contain bent tip at the end. Upper portion of the probe is covered with the nonconductive material to avoid hazards. Curvilinear tips are fine enough to touch the exact point(s).

Chip Configuration

Chip configuration electrical test probes are used for highly integrated circuits. These probes contain a specialized tip to be touched to a microchip technology based highly integrated circuits and devices.

Alligator Clip

Alligator clip electrical test probes contain clips instead of tips. These serrated clips tightly grip the naked wires coming out through the circuits. Besides these common structures you can find extended-fine tip electrical test probes, probe cards, pincher, pin ‘n' socket, flat blade, hook style, spade lug, spring loaded, and wireless electrical test probes.

Electrical Test Probe Performance Specifications

Performance of an electrical test probe mainly depends upon attenuation factor. Attenuation means how much is the error in the amplitude of the real signal and measured signal. Measured signal is the signal that is measured with selecting different ranges on the test equipment. In simple words the test equipment allows various scaling levels for the signal measurement. So a test probe offers a specific attenuation factor that indicates the error in the amplitude at various scales.