.. frequent Design Idea (DI) author Christopher Paul showcased an innovative and high performance true-two-wire current source using a depletion mode MOSFET as the pass device in “A precision, voltage-compliant current ...
.. circuit, if carefully built, is determined by T 2 's interwinding capacitance. Using the core specified, plus 24-gauge wire with Teflon insulation, the resultant interwinding capacitance is less than 0.2 pF. Acquisition delay from the ...
.. interesting analog design problem is the precision current source. Many good designs are available, but most are the three-wire types that can be used as a positive (see Figure 1) or a negative (Figure 2) polarity source, but not both from ...
.. record, and control these process parameters. This equipment will supply 24 VDC to a typical transmitter through one wire and receive current proportional to the process parameter through another wire. Typically, two wires are needed ...
.. ideally be in a TO-220 or similar package if V LOOP 15 V. References Woodward, Stephen. Simple but accurate 4 to 20 mA two-wire transmitter for PRTDs. Williams, Jim. Signal Conditioning for Platinum Temperature Transducers. Materials on the ...
Accurate, inexpensive, and mature platinum resistance temperature detectors (PRTDs) with an operating range extending from the cryogenic to the incendiary are a gold (no! platinum! ) standard for temperature measurement. Similarly, the 4 to 20 mA ...
.. parameter for excitation symmetry) is reduced to a usually insignificant 10/10 5 = 100 µΩ. The component lead wire and PWB trace resistance will contribute (much) more unless the layout is carefully done. Matching resistors to ...
.. is 0.000001 ohms. I often use it to measure contact resistance of a relay or the resistance of big chunk of heavy gauge wire or the resistance of a copper trace on a circuit board. You can also use it to measure the voltage drop of a ...
.. or higher line-to-line three-phase voltage. You can feed this value from two or three phases with or without the neutral wire or from just one phase with the neutral wire. This circuit omits two diodes from the typical three-phase ...
.. “DIY RTD for a DMM” ( Ref. 1 ). With a fortnight’s struggle, I completed the design of 4 mA to 20 mA, two-wire temperature transmitter using a platinum resistance temperature detector (RTD) sensor, as shown in Figure 1. ...