Portable software defined transceiver: Power amplifier

Jason has been working on a portable software defined transceiver design for the past year. Every day this week he’ll discuss a different part of the hardware in a series of guest posts. You can chat with the designer in the forum.  Today’s post is about the power amplifier. Since this project is designed for […]

7400 competition entry: Discrete logic amplifier

Haley0918 added another entry to the Open 7400 Logic competition:  Discrete logic amplifier: This is my second entry for the 7400 logic competition. It’s a discrete logic amplifier made of mostly discrete logic chips. This amplifier is a continuation of my previous discrete logic preamp. The main objective here is to amplify the input signal […]

App note: Extending the input voltage of op-amps

An app note on extending the  input voltage range of standard op-amps: Using its own output to bootstrap a low-dropout voltage regulator (MAX6771) with high input-voltage range (up to 76V), this circuit extends the input range of a CMOS op amp (MAX4162) while preserving its high input impedance and very low input bias current (< […]

App note: Overvoltage protection for amplifier outputs

rsdio writes:   this circuit includes one of my favorites: a dual, common-cathode diode package To protect audio amplifiers and other automotive electronic circuits in the event of an accidental direct connection to the car battery voltage, add the circuitry shown (a shunt regulator, diodes, and an n-channel MOSFET in series with each audio path).

Low-noise rail-to-rail op-amps extend battery life

rsdio writes: These are potentially overkill for most DIY, but if you really need small size, low noise, and/or rail-to-rail performance, then they might be just the ticket. Probably a great choice for a DSO front end. With low power, particularly USB 5 V, rail-to-rail capabilities can be really important. Low-Noise, CMOS-Input, Rail-to-Rail Op Amps […]

App note: High-voltage, programmable-gain current monitor

Another article that might help with bench power supply designs: This circuit monitors current flow at high voltage (48V and higher) using a standard 5V difference amplifier (MAX4198) referenced to ground. It also employs a digital potentiometer (MAX5402) for gain adjustment. Thanks rsdio!

LM0901a1411090451C polis operational amplifier

Akos tips us to the LM0901a1411090451C polis operational amplifier: The LM0901A1141090451C is a macropower, low performance, degraded circuit operational amplifier designed to have a no load power dissipation of less than 0.553W at Vs = ±1pV and less than 200W at Vs = ±2pV. Open loop gain is greater than 0.001k and input bias current […]

App note: Load-power monitor improves high-side current measurements

This amplifier with an analog voltage multiplier could be useful in a bench power supply: Combining a high-side current-sense amplifier with an analog voltage multiplier, the MAX4211 can easily measure the power dissipated in a load. One multiplier input connects to the load voltage, and the other to an internal analog of the load current—that […]

App note: High-quality white noise generator

A white noise circuit could be interesting part of a modular synthesizer. This design has no 1/f component, meaning no annoying repeating sounds in the white noise. In this noise-generator circuit, the amplifier (MAX4238) has no 1/f component in its input voltage noise. It amplifies its own input-voltage noise with a feedback network made with […]