The autoreferencing circuit nulls out the error of a sensor, such as a pressure transducer, at its reference level – for example, at ambient pressure. The circuit is an analog-digital-feedback control system that uses a digitally programmable potentiometer to provide the variability...
Autoreferencing circuit nulls out sensor errors
Low-dropout linear regulators deliver constant currents
Linear voltage regulators offer a simple method of producing a constant current by connecting a fixed resistor between the regulator's output and ground nodes. The regulator's constant output voltage produces a constant current through the resistor...
High-voltage, high-frequency amplifier drives piezoelectric PVDF transducer
Piezoelectric transducers find use in NDE applications. The PVDF transducer has many advantages, including a wide bandwidth and high sensitivity. These transducers require high-voltage and wide-bandwidth amplifiers...
Circuit lets you measure zener voltages and test LEDs
To measure a zener diode’s breakdown voltage, you need a dc voltage source whose voltage exceeds that of the zener voltage...
AC voltage zero cross detector
This project provides AC voltage zero-cross timing detection and a DC voltage after diode rectification with high accuracy. Possible applications for such circuits are AC motor controllers, AC lamp controllers, AC Dimmer Controllers, Home Appliances...
MOSFET shunt regulator substitutes for series regulator
You would normally use a series linear regulator or a dc/dc converter to obtain 3 V dc from a higher supply. However, when breadboarding a concept, you may be able to use a shunt regulator, especially if a series regulator of the correct voltage is unavailable...
Cancel PWM DAC ripple and power supply noise
Several years ago, I published a design idea “Cancel PWM DAC ripple with analog subtraction," showing a simple trick for the cancellation of PWM output ripple. It employs passive summation of the usual PWM signal with its AC-coupled inverse, thus dramatically attenuating the undesired AC component...
Analog peak detector frames mechanical bounce, quantifies contact resistance
Mechanical bounce often occurs while trying to measure current or resistance on experimental materials or from routine switch-contact action. It can be a problem if you are trying to preserve the bounce or noise phenomenon within the measurement system itself...
Shunt circuit clips large transients or regulates voltage
The circuit is a high-power analog of the popular TL431 programmable shunt regulator. This two-terminal circuit is convenient when the drain of the P-channel FET is grounded, since it needs no isolation from a grounded heatsink. There is no mirror analog of the TL431 however...
Improved current monitor delivers proportional-voltage output
This Design Idea expands the capabilities of a previously published one. The original version featured a current transformer whose secondary winding formed part of an oscillator's tank circuit...