Given two batteries, it chooses the one to connect to the load based on the voltage measured at their poles. It can also be used to switch DC power supplies. The growing demand for portable devices capable of working where there is no power grid or ...
Circuits such as the design described here implement useful tools for a diversity of calibration and testing applications A two-wire loop current generator is a useful tool for the testing, calibration and commissioning of current-to-pressure (I/P) ...
If your favorite tool is a hammer, every problem will look like a nail. Abraham Maslow Given how often I tinker with the LM555 and LMC555 analog timers, Maslow might have written that famous aphorism specifically for me. And it. Well, here I go ...
In process industries, field contacts from pressure, temperature, flow switches, limit switches, push buttons, etc., are read by programmable logic controllers and/or distributed control systems (PLC/DCS) through digital input modules. They are ...
For decades, I’ve had a fascination with voltage-to-frequency converters and the 555 analog timer chip, and therefore a double obsession with VFCs based on the 555. In fact, my first Design Ideas (DI) submission (in 1974) was for a 555 VFC. ...
The pages of Design Ideas (DIs) have recently been awash in a veritable cascade of designs for variable frequency oscillators with frequency ranges tunable over multiple decades: Self-oscillating sawtooth generator spans 5 decades of frequencies ( ...
It is well known that a 555 timer in astable mode can be frequency modulated by applying a control voltage (CV) to pin 5. The schematic on the top of Figure 1 shows this classic 555 VCO. Modulating pin 5 has some severe drawbacks: The control ...
The circuit uses a very inexpensive C-MOS IC that is connected to a small photodiode. Using a unique inductive feedback network, the circuit provides high sensitivity under high ambient light conditions. It is a great circuit when you want to ...
Recently, frequent and favorite contributor Nick Cornford gave us a cool and novel acoustic-interface design for a super sub-ohmmeter capable of audibly sniffing out defects in PWBs: “Tuneful track-tracing” ( Ref. 1 ). Figure 1’s ...
Frequent contributor R. Jayapal recently shared an interesting Design Idea (DI) for power supply control and sequencing in MCU-based applications that combine analog and digital circuitry: “Short push, long push for sequential operation of ...