Creating a sample - hold circuit in Multisim

[Josh_E]

Introduction

A sample-hold circuit is a fundamental part of an ADC (Analogue to Digital Converter) circuit. It allows a voltage to be held whilst ADC circuitrys convert the voltage to a digital value. Essentially, it allows the incoming signal to be sampled at a specified rate.

Creating one in Multisim is very easy, and can be used to re-create an ADC circuit.

The picture above shows the result of sampling a 10Hz sine wave every 0.5 seconds or so. The result is the output of the circuit is the incoming voltage at a certain sample time.

This is achieved using a switch to sample the circuit. In real life, you may choose to replace this with a transistor.

The circuit (shown below) is very simple using a voltage follower and a capacitor.

[Paulo_C]

how did you obtain that waveform? the one on the first image.
Because when i run the simulation I just get the sine wave or the value it's in when i press space, but i can´t get something similar to what you got there. Thanks