Circuits & Schematics - Measurement - 8

Low-cost monolithic precision adjustable voltage references are available in multiple families from multiple manufacturers, but this isn’t true for adjustable precision current references. That’s unfortunate, because while most ...

It is known that the p-n diode can be the basis of an accurate thermometer for cryogenic temperatures up to about 200 C. A constant current is maintained through the diode and the voltage across it gives an indication of the temperature. The ...

Numerous applications require the measurement of very low resistances, including but not limited to fuse integrity analysis, relay characterization, and superconductor evaluation. There is a wide range of commercially available equipment designed ...

Long ago in a galaxy far away (actually, the same galaxy but the Milky Way is moving so it must logically be far away from where it was way back then), I sketched up a simple circuit for a DC coupled amplifier that I thought (in my youthful ...

Sensors that detect and track small metallic objects are handy gadgets, whether used to route workpieces on an assembly line or comb a beach for “treasures” lost in the sand. A typical sensor design consists of an inductor integrated ...

LVDTs (linear variable differential transformers) are electromechanical measuring devices that convert the position of a magnetic core into electrical signals. You generate these signals via excitation on the primary side. The results on the ...

Almost all precision voltage-to-frequency converters (V-F) utilize charge pump based feedback for stability. These schemes rely on a capacitor for stability. A great deal of effort towards this approach has resulted in high performance V-F ...

The accurate, high-side, current-sense circuit in Figure 1 does not use a dedicated, isolated supply voltage, as some schemes do. Only the selected transistors limit the common-mode range. The circuit measures the voltage across a small ...

Powering portable telemetry systems for long-term monitoring presents interesting design challenges. Batteries are unsuitable for certain critical applications, and, in these circumstances, designers typically use wireless inductive links to ...

Laser diodes can destroy themselves in a few nanoseconds, so testing the response and stability of a feedback-stabilized laser-diode driver can be expensive. The simulator circuit in Figure 1 shows a typical laser-diode package, which contains not ...