Wideband Digitally Programmable Gain Amplifier - The LTC6910 is a CMOS
programmable gain (from 0 to 64) amplifier. The amplifiers provide for a differential input signal and for dc biasing the output into a precise voltage reference based level in a single supply design. __ Linear Technology/Analog Devices App Note, Mar 16th 2010
Wien Bridge Oscillator - The opamp Wien-bridge oscillator provides a nice view into classic oscillator design using feedback analysis. Feedback analysis reveals if your circuit is stable (well behaved) or unstable (may oscillate). When designing amplifiers (especially high-speed ones), the trick is to avoid the conditions that make the circuit oscillate. When designing oscillators, you strive to achieve those conditions in a predictable way.
Wien Bridge Oscillator Rail-to-Rail Sine Wave Generator - Circuit Ideas for Designers App Note __ Advanced Linear Devices, Inc
Wireless Switch - Normally, home appliances are controlled by means of switches, sensors, etc. However, physical contact with switches may be dangerous if there is any shorting. The circuit described here requires no physical contact __ Electronics Projects for You
Yield Accurate Absolute Values - 07/05/01 EDN-Design Ideas The circuit in Figure 1 delivers the absolute value of the input signal with an accuracy better than 10 ppm of the full-scale range. The circuit has low zero-crossing error. You can use it as an asynchronous demodulator, as a source __ Circuit Design by Marco Pisani, Istituto di Metrologia G Colonnetti, Turin, Italy