Oscilloscope is a commonly used testing tool for electronic engineers and enthusiasts to observe and analyze the waveform characteristics of electrical signals. Mastering its usage can greatly improve the efficiency of circuit debugging.

The core components of an oscilloscope are:

Display screen: displays voltage time waveform, grid lines (grids) are used to measure parameters.

Channel input: There are usually 2-4 independent channels (CH1/CH2, etc.), each of which can be connected to a test probe.

Vertical control: Adjust the voltage scale (V/div), offset (Position), and coupling mode (DC/AC/GND).

Horizontal control: Adjust the time scale (s/div), scanning mode (automatic/single/trigger), and trigger position.

Trigger system: Control the starting point of waveform display to ensure stable observation of repeated signals.

Probe usage

Passive probe: The most common and requires calibration compensation (by adjusting the knob on the probe to match the input capacitor).

Active probe: used for high-frequency or low-level signals, requiring independent power supply.

Grounding clip: It must be firmly connected to the "ground" of the tested circuit to avoid the formation of loop interference.

Advanced debugging techniques for oscilloscopes:

1. Capture transient signals

Single trigger+high sampling rate: Set the scanning mode to "Single", reduce the time scale (such as 10ns/div), and capture burrs or overshoot.

Peak Detection: Enable the "Peak Detect" function to capture pulses shorter than the sampling interval (such as spikes 10ns wide).

2. Analyze power ripple

AC coupling+narrow bandwidth: Set the coupling mode to AC and limit the bandwidth to 20MHz (to reduce high-frequency noise interference).

Long afterglow mode: Observe the envelope changes of low-frequency ripples.

3. Measure phase difference

Dual channel trigger: Set CH1 as the trigger source and connect CH2 to another signal.

Lissajous figure: Switch to X-Y mode and observe the phase relationship between the two sine signals (the inclination angle of the ellipse reflects the phase difference).

4. Protocol decoding (supports oscilloscopes)

Enable serial decoding: Select protocols such as I2C, SPI, UART, etc., and set the baud rate or clock frequency.

Decoding result: The screen displays bus data (such as address, data, read/write direction), accelerating communication debugging.