Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [buffer]

A circuit or sub-circuit that as accurately as possible preserves the voltage characteristics of a signal while providing additional current. Typically used in situations where a circuit cannot drive the load that is presented to it.

A circuit or sub-circuit that as accurately as possible preserves the voltage characteristics of a signal while providing additional current. Typically used in situations where a circuit cannot drive the load that is presented to it.

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What is the purpose of a buffer gate?

As I understand a buffer gate is the opposite of a NOT gate and does not change the input: However I sometimes see buffer gate ICs used in circuits and to an inexperienced eye they seem to do nothing at all. For example recently I've seen a…
I have no idea what I'm doing
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Inverting buffer with op-amps

I know that it's easy to make a unity gain buffer with an op-amp (as a voltage follower): simulate this circuit – Schematic created using CircuitLab I also know that it's easy to make an inverting buffer with an op-amp (an inverting amplifier with…
Greg d'Eon
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Op-amp inverter followed by buffer. Why?

In a schematic I've been trying to understand I came across this sub-circuit: It's an op-amp inverter directly followed by a buffer. VIN comes from a DAC in a microcontroller and this circuit produces a VOUT which is negative VIN. The op-amp is…
mcmayer
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Stability problem in unity-gain opAmp

As a part of a controlled power supply for hardware-in-loop testing for a student driven project, I had to develop a current buffer (voltage follower) which could source up to 1 A. I had the (bad) idea of trying to implement this simple…
svilches
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Why are BJTs common in output stages of power amplifiers?

From my understanding, the role of the output stage is to decrease the output impedance to almost 0. For that, MOSFETs seem better suited since they've got way lower \$R_{ds}\$. Yet I see quite often BJTs as buffer in discrete design, often in a…
Jonas Daverio
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What is the purpose of an AND gate with the same signal on both inputs?

If this is a buffer, why use an AND gate, aside from better availability of that gate in a single package? This is on an Analog Devices SHARC eval board.
jars
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Using an op amp as a buffer

Working on a project where we're using a couple of OP470 Quad Op amps. There are 2 unused op amps, and I need to buffer a signal coming from a sensor (this is according to the sensor's data-sheet). I'd like to use one of the extra op-amps. I know…
Skaevola
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What is the basic idea behind the so-called "diamond buffer"?

The idea for this question came about after I wrote an answer to a similar question. This "diamond solution" was something unknown to me. I took a look at Wikipedia page (see the picture below) and it immediately impressed me. (The picture is taken…
Circuit fantasist
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This op-amp buffer is oscillating and I can't figure out why

Currently, this is the only assembled part on the circuit board. This is a simple inverting buffer circuit that should be at the input. The op-amp (LTC6241HV) is powered +/-5V from a linear bench power supply. The power pins are bypassed with 0.1uF…
user733606
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Is this clamping voltage divider for a high-impedance input a good, robust design?

I have an AC input as follows: Can range from ±10V to at least ±500V continuously. Runs from roughly 1 Hz to 1 kHz. Needs > 100 kΩ of impedance on it, otherwise its amplitude changes. May occasionally be disconnected and subject the system to ESD…
JohnSpeeks
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Is it a good idea to connect a line buffer to ground?

Got a quick question. I'm dealing with 74VHC125BQ,115 and I won't be using one of the line drivers; the rest are connected to UART. So, I'm wondering what I should do with the last one. Is it a good idea to ground its input or should I just leave it…
scriptsNgiggles
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Is ping pong buffer the same thing as a double buffering?

In ping pong buffer we have two buffers, when one is being written by upstream component, the other is being read by the downstream component. When writing into one buffer is completed, the downstream component will switch to reading that as the…
quantum231
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Buffering a Digital Microcontroller Signal for Connecting to an Optocoupler

I frequently work on projects in which I use optocouplers for isolating digital +5VDC control signals (for example, from a microcontroller) from the rest of the circuit. However, since these work by illuminating an LED inside the device, there can…
teeeeee
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Help with power-loss protection using capacitor

I designing a circuit will store log data to an SD card. The information will be coming form a parent circuit that this one plugs into. The parent circuit will supply 5V to my daughter card. The daughter card uses an MCU that operates at 3.3V so I…
PICyourBrain
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Chosing a pulldown resistor

Setup: A digital output from a device is connected to an output buffer to drive an optocoupler. If device power is lost the output will go in high-impedance mode. Problem: I want to make sure that the buffer output is low when device power is…
mola
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