In the design of unmanned aerial vehicles (UAVs) for air cargo transportation, the DO-160G standard for environmental adaptability of airborne equipment is a core threshold for ensuring the reliability and safety of the equipment. Core components must pass strict "Electromagnetic Susceptibility (EMS)" tests - this is crucial for ensuring stable operation of the UAVs in scenarios such as high-altitude surges, transient impacts, and extreme temperature and humidity. Shanghai Leiditech’s EMC series devices (surge suppression modules, transient current suppression modules, EMI filter modules) precisely match the chapter requirements and parameter standards of the DO-160G EMS tests, providing an "authoritative matching solution" for the components to pass the certification smoothly.

The Core Challenges of DO-160G Standard and the Response Strategies of Shanghai Leiditech Devices

The EMS test of DO-160G focuses on "anti-interference capability", with key test items such as power supply transient, electromagnetic sensitivity, and lightning-induced transient being the core. The design of each module of Leiditech Shanghai fully complies with the corresponding test requirements and meets the test standards.

1. Surge Voltage Suppression Module: Meeting Surge and Lightning Protection Requirements

During flight, UAVs may encounter two types of voltage surges: one is the regular surge caused by power switching, and the other is the transient voltage induced by lightning strikes at high altitudes. Both of these scenarios need to meet the testing standards of DO-160G.

The dual-scenario protection capability of the Leiditech Shanghai LMVS series surge modules is directly tailored to meet the requirements: 

-        Regarding surge testing: The module can clamp the 80V to 100V transient surge voltage to 38V within 50ms (based on actual measured data), which is lower than the "load safety voltage threshold" stipulated by the standard, thus preventing the DC-DC converter and sensors from being damaged.

-      Applicable scenarios and parameters: DC operating voltage 28V, covering rated current range of 1A to 50A. For example, LMVS2850AH1 (50A, 1/2 brick package) can meet the protection requirements of the power system, with working shell temperature ranging from -55℃ to +125℃. It is compatible with both the low-temperature conditions at high altitudes of UAVs and the high-temperature conditions of equipment.

2. Impulse Current Suppression Module: Overcoming the Challenge of Power Supply Transient Impulses

DO-160G clearly stipulates: "The transient current during the startup of onboard equipment should be less than 10 times the rated current". However, when an UAV is powered on, the charging of capacitors can generate a 65A surge current (in the case of a 470μF capacitor), which far exceeds the standard limit.

The "flow reduction capability" of the Leiditech Shanghai LMIS/LMESW series modules precisely meets this requirement: 

-        The actual measurement results show that the module can reduce the 65A impulse current to 12.67A (in the same capacitance scenario), meeting the surge protection requirements of the DO-160G Chapter 19 electromagnetic sensitivity test. 

-        Function Compatibility: Some models (such as LMESW-560WDC28V-N10E) support anti-reversal function, meeting the additional requirements of Chapter 19 "Anti-Reverse Protection", and also support remote control for activation/deactivation, meeting the intelligent control requirements of unmanned aerial vehicles; 

-      Low depletion advantage: The conduction resistance is as low as 0.005Ω, which not only suppresses the impact current but also reduces power consumption, conforming to the "high energy efficiency" design principle of unmanned aerial vehicles.

3. EMI Filtering Module: Ensures EMI compliance and enhances the stability of the EMS system.

In the EMC certification process, although the CE102 test of GJB151 focuses on "noise control", the high-frequency noise of the components themselves can indirectly affect the anti-interference capability of the EMS.

Leiditech Shanghai’s LMFL series EMI filters can simultaneously solve this problem: 

-        Performance meets standards: The common-mode insertion loss is up to 44 dB (at 1 MHz), and the differential-mode insertion loss peaks at 100 dB (at 1 MHz). This meets the requirements of GJB151 CE102 Class 3 (conductive emissions ≤ 66 μV in the 150 kHz to 10 MHz frequency range).

-        Integration advantages: Some models (such as LMFL2820X00Q) can integrate the current suppression function for surges. While meeting EMI compliance, it further enhances the power supply transient protection capability as per Chapter 19, reducing the number of components and compatibility risks.

Case: Testing and verification of the power system for a certain type of unmanned aerial vehicle in accordance with DO-160G standards

After being equipped with the Shanghai Leiditech EMC LMFL2820X00Q filter module and the LMVS4366-2809BE surge module, a certain model of unmanned aerial vehicle successfully passed the DO-160G test: 

Conduction emission test: The noise level was reduced by 32 dB compared to the situation without the module installed, which was much better than the standard limit.