Sorry, you need a Java-enabled browser to see the simulation.

This is a Class D or switching amplifier circuit. It amplifies the 30 Hz signal to the upper left. First, it compares the input to a high-frequency triangle wave, using a op-amp as a comparator. It uses the output of the comparators to drive two MOSFETs which bring their output to +15 V if the output is higher than the triangle wave, or -15 V if it's lower. Since the triangle wave sweeps up and down at high frequency, we get a series of spikes, which are higher on average when the input is higher. An LC filter smoothes out the spikes to generate the amplified output.

Next: Half-Wave Rectifier (inverting)
Previous: Log Amplifier
Index




java@falstad.com
Generated Tue Feb 23 2010