Tag Archives: amplifiers

Class-D Audio Amplifiers with Wide Supply Range and High Switching Rates

Texas Instruments has introduced three analog-input class-D stereo amplifiers for use in soundbars, after-market automotive solutions, portable audio docks, and LCD televisions. The TPA3116D2, TPA3118D2 and TPA3130D2 feature the industry’s highest programmable switching rate and widest power supply range, enabling audio output that is both high quality and highly efficient. The devices are pin-to-pin and software compatible and can support a single-layer printed circuit board (PCB), enabling cost savings by allowing designers to reuse a single layout for multiple designs. [via]

Class-D Audio Amplifiers with Wide Supply Range and High Switching Rates – [Link]

TI Technical Articles

focus.ti.com writes:

Here you can find links to technical articles written by TI engineering experts for engineering trade magazines. Topics include how to select or design with amplifiers, data converters, clocks, interface and power management. They also address applications, such as audio, industrial, medical, high reliability and many others. Several sorting options can help you with your search

TI Technical Articles – [Link]

The Story of the LM13600/LM13700 Transconductance Amplifiers

A neat write-up about this fun little chip, written by co-designer Don Sauer: [via]

The LM13600 was designed by Bill Gross and myself in less than 5 minutes. At the time the Consumer Linear IC design group was training a new mask designer. We needed something with a few transistors for her to learn how to arrange them in a optimum circuit arrangement while using minimum silicon area.

At the time, electronic Organs were being done using analog circuitry. I had just made a trip to one such company and of course they gave me a wish list of what kind of circuits they would like to see. The RCA 3080 has just come out and it almost gave the Analog Organ folks everything they wanted. They needed something for analog variable gain. The application was to shape the attack and decay of various waveforms.

But the 3080 was a true Operational Transconductance Amplifier in that it had a voltage input and a current source output. For most applications, an external buffer was needed.

At the time we were considering second sourcing the 3080 anyway. Also at this very same time, the 16pin plastic dip package had just been developed. So the development spec for the LM13600 was that it needed a schematic to train someone in IC layout. It needed to have 16 pins. And we were going to layout the 3080 anyway. The schematic part was easy. Just used the 3080 exactly. There were 16 pins, so we could just mirror the layout to do a stereo. That left 3 extra pins per channel. The simplest buffer was a darlington which needed two pins per channel. There were complaints about high levels in input signal generated too much distortion in the 3080. That could be addressed by connecting the left over pin to predistortion diodes.

The Story of the LM13600/LM13700 Transconductance Amplifiers – [Link]

App note: Extend range of current-sense amplifiers

A current-sensor would be useful in a lab power supply. This app note is about chaining two current-sense chips to use at high voltages: [via]

Using a transistor as shown, you can double the allowed voltage limit on a current-sense amplifier by stacking two such amplifiers one upon the other. The voltage signal from the bottom amplifier then represents current as the voltage across the sense resistor, times the product of the gains of the two amplifiers.

App note: Extend range of current-sense amplifiers – [Link]

Portable Audio Amplifiers

Above circuits are based on TEA2025 is a monolithic integrated audio amplifier in a 16-pin plastic dual in line package manufactured by UTC .Circuit has an Internal Thermal Protector. It is designed for portable cassette players and radios.

Portable Audio Amplifiers – [Link]

DIY Audio Projects


diyAudioProjects.com has a great collection of DIY audio Projects. DIY Audio Projects documents several DIY HiFi audio projects for Audiophiles. Projects include vacuum tube amplifiers, gainclones (chip amps), mosfet amps, preamplifiers, loudspeakers and cables. Visit the link below to check it yourself. Sure you will be amazed!

DIY Audio Projects – [Link]

Single supply operation amplifiers versus dual supply


scienceprog.com writes:

We used to see dual supply ideal operational amplifiers (Op Amps), what means that Op Amps are powered from dual supplies with equal magnitude and opposing polarity. The center tap is connected to the ground which serves as a center of the supply voltage.

Single supply operational amplifiers are powered with single polarity voltage. In this case you loose convenient ground reference that split supply op amps have. In this case you must ensure that signal swings between correct voltages (eg. VCC and GND) …

Single supply operation amplifiers versus dual supply – [Link]