Half-Wave Rectifier is a runnable microcontroller simulation example on SensBench — open the wired circuit, inspect the code, and compile real firmware in your browser, no install needed. Last updated Aug 14, 2026.

FREE SIMULATOR EXAMPLE · INTERMEDIATE

Half-Wave Rectifier

This example samples a half-wave rectifier on the Arduino Uno’s A0 at 200 samples per second — open the Serial Plotter and watch the diode pass only the positive half-cycles. It is an oscilloscope made from an ADC and a plotter window.

▶ Open in the SimulatorGet the parts
Board Arduino Uno (ATmega328P) + analog SPICE circuit
Difficulty intermediate
Category circuits
Libraries None — just the Arduino core
Runs in Sensbench browser simulator — free, no account
Arduino Uno sampling the half-wave rectified output of a diode on A0 at high speed in the Sensbench simulator

The exact circuit you get when you open this example — already wired, ready to run.

The sketch

// Half-wave rectifier — observe on Serial plotter
void setup() { Serial.begin(115200); }
void loop() {
  int raw = analogRead(A0);
  Serial.println(raw);
  delay(5);
}

How it works

The circuit is a single diode in series with the signal — the simplest possible rectifier. The sketch samples A0 every 5 ms and prints the raw ADC value, relying on the IDE’s Serial Plotter to draw the waveform. No averaging, no filtering — the raw shape is the lesson.

At 200 samples per second the plotter shows the rectified half-sine: rising and falling bumps with flat zero periods in between. The 115200 baud rate keeps the serial stream ahead of the samples so the plotter stays real-time.

Before you build it for real

A real diode drops about 0.7 V (silicon) when conducting — the rectified output is not just half the wave, it is the wave minus 0.7 V, so low-amplitude signals come out nearly flat. The ADC also cannot read negative voltages: the blocked half-cycle reads 0, not the true negative swing, and feeding a negative voltage below -0.5 V can damage the pin. And the 5 ms sampling aliases anything above 100 Hz — faster input signals produce misleading traces; Nyquist applies to your plotter too.

Get the parts

Solderless Breadboard 830-Point In the simulator it is free — this is for your real bench.Jumper Wires M-M 40pcs In the simulator it is free — this is for your real bench.

Related examples

Schottky Reverse ProtectionRun in simulator →Zener Voltage RegulatorRun in simulator →Capacitor Charging CurveRun in simulator →

FAQ

Why sample every 5 ms?

The rectified waveform is a series of half-sine bumps at the signal frequency. Sampling at 5 ms (200 Hz) captures enough points per bump to see its shape. The Serial Plotter in the Arduino IDE turns the stream into a live oscilloscope trace — this example is designed for the plotter, not the text monitor.

Why does the diode only pass half the wave?

A diode conducts in one direction: forward-biased it passes current, reverse-biased it blocks. An AC input’s positive half-cycles flow through, the negative half-cycles are blocked — hence “half-wave.” The output is DC only in the sense that it never goes negative, not in the sense of being smooth.