Circuits & Schematics - Audio - 4

John Ambrose EDN Tracking notch filters find use in harmonic-distortion analyzers; they also can remove heterodyne noise from ham-radio systems. A conventional tracking switched-capacitor notch filter relies on a bandpass filter, a ...

Introduction A new family of op amps features industry leading speed versus supply current. The LTC6261/LTC6262/LTC6263 family (single, dual, quad) provides 30 MHz at a low 240 uA supply current, with 400 uV maximum offset voltage and rail-to-rail ...

Pierre Corbeil EDN Class B amplifiers are prone to crossover distortion, which occurs in the output stage in which conduction transfers from one transistor to the other. To prevent crossover distortion, a bias current must flow in both transistors ...

Charles Wenzel Techlib.com Here's a general-purpose 2 watt audio amplifier with excellent overall performance. It is easily configured to serve as an audio output stage for lower power applications or as a more powerful amplifier for ...

Richard Kurzrok EDN The low-cost composite passive filter in this Design Idea requires no dc power and can enhance the performance of audio equipment and instrumentation by rejecting power-supply hum and spurious pickup from AM, FM, and low-band ...

Royce Higashi and Tony Doy, Maxim Integrated Products EDN Low-profile piezoelectric speakers can provide quality sound for portable electronic devices, but they require voltage swings greater than 8 V p-p across the speaker element. Yet, most ...

Guus Colman EDN In many applications, the frequency-conversion steps comprise a buffer, preferably with some extra voltage gain; a mixer; and some filtering. Instead of including an amplifier in front of the mixer, you can easily integrate the ...

Troy Murphy EDN Thanks to its property of applying an equal amount of delay to all frequencies below its cutoff frequency, the Bessel linear-phase filter sees service in audio applications in which it's necessary to remove out-of-band noise without ...

The circuit in Figure 1 can help if you must transfer dc power and audio over a pair of copper wires. One application for such a circuit is a low-cost door-opening system with speech input. The circuit uses only one IC, the well-known LM317 , a ...

Marko Kannisto, Maxim Integrated Application Note 5147 Part 1. There are thermal issues to consider. With a 12 V supply voltage and a 4 Ω load, the amplifier's efficiency with 20 WRMS output power is approximately 85%. We can calculate how ...