Archive for category: Audio and Amplifier

Operational Amplifier (Op-Amp) Oscillator

Audio and Amplifier | By: Diagram mania

This is Operational an Amplifier (Op-Amp) Oscillator circuit. This circuit has some advantages, they are this circuit can be operated at low frequencies with relatively small capacitors, it has a completely-symmetrical output waveform along with a buffered output and it will always self start and cannot hang up because there is less dc positive feedback […]

Operational Amplifier and Super Microphone – Video Tutorial

Audio and Amplifier | By: Diagram mania

This is a video tutorial about operational amplifier and super microphone circuit. This video shows how an operational amplifier works and an example of amplifier circuit for microphone. The op amp has five important pins. they are output pin, non-inverting input pin, inverting input pin and negative and positive voltage supply input pin. The output […]

10.7-MHz IF amplifier

Audio and Amplifier | By: Diagram mania

This is 10.7-MHz IF amplifier circuit. This circuit is used in many application such as cell phone base station receivers (final IF) and FM broadcast receivers. The ceramic filter that is used in this circuit are cheap and available in a variety of insertion losses and banwidths. This circuit uses a 230-kHz bandwidth filter SFELA10M7GA00-B0 […]

Differential Low-Pass Filter and The Design Formula

Audio and Amplifier | By: Diagram mania

Multiple Feedback (MFB) is the best filter topology to use for differential low pass filters. Here’s the circuit diagram: To design this filter, a corner frequency is chosen based on harmonic content desired in the waveform. After that, we have to select a value of capacitor. The value of C1 is equal to C and […]

Single Supply Instrumentation Amplifier

Audio and Amplifier | By: Diagram mania

This is a single supply instrumentation amplifier circuit. This circuit can be used to replace the function of conventional differential-amplifier topologies to load the Dc gain on a low level signal. This circuit has high input impedance of non-inverting op-amp inputs. Here is the circuit : This circuit uses single supply, so the strain gauges […]

Audio Decibel Level Meter

Audio and Amplifier | By: Diagram mania

This is a circuit of Audio Decibel Level Meter. This circuit uses the SA604 which not only designed as an RF device but also the Received Signal Strength Indicator (RSSI). In a cellular radio, the radio’s microcomputer uses that function to monitor the received signal strength continuously. A logarithmic response proportional to the input signal […]

Photocells (Photoconductive, Photodiode, and Photovoltaic) Amplifiers

Audio and Amplifier | By: Diagram mania

The figures below show us about amplifiers for photoconductive (top),  photodiode (mid) and photovoltaic cells (bottom). Some voltage dependence of both speed and linearity is displayed by all photogenerators. If the cell terminal voltage is allowed to vary with cell conductance, the current through a photoconductive cell will not display strict proportionality to incident light. […]

VHF (100-450 MHz) 250W Power Amplifier

Audio and Amplifier | By: Diagram mania

Two octave wideband amplifier (covering both the civil and military airbands between 100 and 450 MHz), equipped with two MOSFET devices, which is capable of generating 250 W of output power are given on this design procedures and measurement results report. One of the two octave wideband amplifier has to use the device s with […]

Audio Amplifier with DC Volume Control

Audio and Amplifier | By: Diagram mania

The TDA7052B and TDA7052BT are 0.5 W and 1 W mono Bridge-Tied Load (BTL) output amplifiers with DC volume control. Not only have been designed for use in TV and monitors, but TDA7052B and TDA7052BT are also suitable for use in battery-fed portable recorders and radios. This devices are integrated with a Missing Current Limiter […]

Digital Control for Tone, Volume, and Balance

Audio and Amplifier | By: Diagram mania

Try to imagine the possibilities to integrate full audio tone, balance, and volume control into your multimedia computer product, and you integrate it without having to resort to any manual knobs. Naturally we could integrate it with a bunch of DACs all running under microprocessor control, but what happens if the processor has had a […]