Time:2026-04-10 11:08:43 Browse:
The following are 11 core items for electrical performance testing, systematically organized according to international standards (IEC 62368-1, ISO 16750-2) and Chinese national standards (GB 4943.1), covering definitions, testing methods, standard basis, and key parameters.
1. Overvoltage test
Simulate the scenario of abnormal power supply rise and verify the response capability of the equipment protection circuit.
Test method: Use a programmable DC power supply to slowly increase the input voltage to 1.5 times the nominal value at a rate of 0.1 V/s for 60 seconds, and record the protection trigger threshold.
Standard basis: IEC 62368-1 requires the output voltage to drop below 60V within 200ms after protection action.
Typical applications: mobile power bank, communication power supply, car charger.
Equipment: Programmable DC power supply (such as ITECH IT-M7700), high bandwidth oscilloscope.
2. Overlapping alternating voltage test
Evaluate the impact of AC ripple on electronic devices in DC power supply systems.
Test method: Overlay 1-5V AC (frequency 10Hz-100kHz) on a DC voltage (such as 12V or 24V), continuously apply and monitor for abnormal equipment function or performance drift.
Standard basis: ISO 16750-2 (Automotive Electronics) specifies that the superimposed waveform should be a sine wave, with amplitude and frequency graded according to the application scenario.
Design strategy: Add a π - type filtering circuit to the power inlet, and use an LDO regulator (ripple suppression ratio>60dB) for sensitive circuits.
Typical scenarios: ECU, ADAS module, in car infotainment system.
3. Slow decrease and increase in supply voltage
Verify the stability and self recovery capability of the device under power gradient conditions.
Test method: Slowly increase and decrease the voltage at a rate of 0.5 V/min (such as from 12V to 2V and then back up), and record the device's power-off and restart thresholds.
Standard basis: GB 4943.1 and the testing specification for low-voltage systems of new energy vehicles require that the restart voltage should not exceed the lower limit of the input range.
Key indicators: During voltage drops, unexpected resets, data loss, or functional abnormalities must not occur.
Applicable objects: industrial controllers, medical equipment, battery management systems (BMS).
4. Transient changes in power supply voltage
Simulate voltage spikes caused by sudden load changes or generator load shedding.
Test method: Step up the input voltage from the nominal value to 15V-40V (depending on the system level) within 20ms, and monitor the protection response time.
Standard basis: ISO 16750-2 requires a response time of ≤ 30ms, and the equipment must automatically resume normal operation after the voltage is restored.
Testing equipment: high-speed electronic load, transient voltage generator.
Typical failures: MCU reset, MOSFET breakdown, capacitor overvoltage damage.
5. Reverse voltage test
Test the tolerance of power input terminals or semiconductor devices under reverse polarity.
Test method: Apply reverse DC voltage (such as -12V), measure reverse leakage current and breakdown voltage, with a duration of ≥ 1 minute.
Standard basis: SJ 2215.5-1982 (semiconductor optocoupler) stipulates that the reverse breakdown voltage should be higher than twice the rated operating voltage.
Key parameters: Leakage current should be<10 μ A (at room temperature), breakdown voltage should be ≥ rated voltage × 1.5.
Protection design: parallel TVS diode or reverse diode at the input end.
6. Ground offset test
Evaluate the common mode interference and system stability caused by impedance changes in the grounding circuit.
Test method: Connect a 0.1-1 Ω adjustable resistor in series between the equipment protection ground (PE) and the reference ground, inject 1-5A AC current, and monitor the signal link noise and communication error rate.
Standard basis: ISO 16750-2 and the Automotive EMC Standard (CISPR 25) require that the system function properly when the ground offset voltage is ≤ 1V.
Typical impacts: CAN bus communication interruption, sensor signal drift, ECU misoperation.
Solution: Optimize grounding topology, use isolated power supply, and add common mode filters.
7. Short circuit test
Verify the effectiveness of the protection mechanism when a hard short circuit occurs at the output terminal.
Test method: Simulate a 0 Ω short circuit using a programmable DC electronic load, and measure:
Response time (from short circuit occurrence to protection action)
Protection mode (constant current limiting/hiccup mode/lock off)
Recovery capability (whether it automatically restarts after the short circuit is resolved)
Standard basis: IEC 62368-1 requires a response time of ≤ 100ms and must not cause fire or component explosion.
Test equipment: high sampling rate oscilloscope+current probe (bandwidth ≥ 100MHz).
8. Open circuit test
Verify the voltage stability and no-load behavior when the output terminal is disconnected.
Test method: Disconnect all loads and monitor whether the output voltage drifts, oscillates, or exceeds specifications (such as ± 5%).
Standard basis: IEC 62368-1 requires that the no-load output voltage shall not exceed 110% of the rated value and there shall be no continuous oscillation.
Typical problems: Unstable feedback loop, optocoupler aging leading to voltage surge.
Design points: Increase no-load discharge resistance or use constant voltage control IC.
9. Voltage endurance test
Assess the breakdown risk of insulation systems under high voltage.
Testing method:
DC withstand voltage: Apply 6kV DC for 1 minute
AC withstand voltage: Apply 4kV AC (50Hz) for 1 minute
Standard basis: GB 4943.1 specifies the voltage and time for insulation strength testing.
Qualification criteria: No breakdown, no flashover, and no sudden increase in leakage current during the testing period (leakage current limit is usually ≤ 5mA).
Equipment: High voltage withstand tester (such as ZHZ8D), grounding protection device.
10. Insulation resistance test
Measure the insulation resistance between live parts and accessible metal components.
Test method: Use a megohmmeter to apply 500V DC and measure insulation resistance for 60 seconds.
Standard basis: IEC 60950 and GB 4943.1 require an insulation resistance of ≥ 10 M Ω (which can be relaxed to 2 M Ω in humid environments).
Operation points: Power off and discharge before testing; After testing, safely discharge the capacitor.
Equipment: Digital megohmmeter (such as ZC25B-3), automatic insulation tester.