A handheld digital multimeter (DMM) is a portable electronic test tool that integrates multiple measurement functions. It features a digital display for direct readout, high accuracy, and ease of use. The following is an analysis of its core features and functions:

• The LCD screen directly displays measured values, with mainstream models displaying values ranging from 3999 to 9999 digits.
• Some high-end models support visual data displays such as bar graphs and trend charts.

• Traditional models use a rotary knob to switch between modes (such as voltage, current, and resistance).
• Newer touchscreen models support intelligent shifting and touch-sensitive operation.

• Voltage: AC/DC voltage measurement (ACV/DCV), with ranges from millivolts to 0.1 volts. Kilovolt level
• Current: Supports AC/DC current detection, with some models offering a 20A high current range
• Resistance: Quickly detects circuit impedance or continuity using the ohm range (Ω)

• Capacitance/Frequency: Directly displays capacitance (in pF to mF) and signal frequency
• Semiconductor Testing: Diode forward voltage drop, transistor gain factor (HFE), etc.
• Temperature: Requires an external temperature probe, supports °C/°F switching

• Digital multimeters offer higher accuracy and include new measurement functions such as capacitance and frequency

• Circuit maintenance: Quickly locate shorts, opens, or component failures
• Power supply operations and maintenance: Non-contact voltage detection (NCV) and neutral/live wire identification
• Electronic R&D: Analysis of signal parameters such as frequency and duty cycle

By integrating high-precision measurement with intelligent design, handheld digital multimeters have become essential tools for electronics engineers, electricians, and hobbyists.