This article describes the partial ESD immunity test for the entire vehicle.
Classification according to discharge mode can be divided into direct contact discharge and air discharge.
1. The discharge test point shall include at least all power switches and control devices accessible to members of the passenger compartment. Welcome to include buttons, levers, and handles for normal operation of the vehicle.
2. Direct contact discharge is direct contact discharge to the accessible discharge point according to the specified test limit. The number of discharges is generally at least 3 times positive and negative at each point, and the discharge interval is at least 5S. The specific discharge times are specified according to the customer test plan. .
3. The air discharge is to discharge the product in the air according to the specified test limit. The air discharge end should be at least 15mm away from the equipment under test, and the discharge end should be perpendicular to the discharge position (±15°C). More than 5mm/s is slowly approaching until discharge. If no discharge occurs, continue to move the discharge end until the discharge end is in contact with the discharge point. If no discharge is still generated, the test at this position and the voltage level is stopped. The number of discharges is generally at least 3 times positive and negative at each point, and the discharge interval is at least 5 seconds. The specific number of discharges is specified according to the customer's test plan.
After all the test points of the equipment under test are subjected to the discharge test with the specified positive polarity and negative polarity power supply levels, the tested equipment shall be subjected to all available functional tests. In general, the functional status shall be the same as specified in Table B below. The following table is taken from GB/T19951-2001), and the specific functional status should be based on the level specified in the test plan.
B3. Functional status classification
The following is a list of all functional categories for all devices or systems.
Note: “Function” here refers to the function performed by the electronic system.
- Class A: The device or system performs all functions of its face shell design during and after exposure to interference.
- Class B: A device or system can perform all of its pre-designed functions during exposure to interference; however, one or more of the indicators exceeds the specified deviation. All functions automatically return to the normal allowable range after removing the direct exposure interference. Pre-designed features maintain Class A levels.
- Class C: A device or system does not perform one or more of its pre-designed functions during exposure to interference, but automatically returns to normal operation after removal of direct exposure interference.
- Class D: The device or system does not perform one or more of its pre-designed functions during exposure to interference until it is removed from the direct exposure interference and is automatically restored to normal after a simple "operation or use" reset action. Operating status.
- Class E: A device or system does not perform one or more of its pre-designed functions during and after exposure to interference, and cannot resume operation if it is not repaired or replaced.
1. Vehicle part Human body ESD discharge model
2. Connect the ESD body simulator ground cable to the body part of the passenger compartment (as shown below):
The test of the whole vehicle is carried out under the active driving and idle speed of the engine of the vehicle. If the test procedure involves using a dynamometer to drive the test system at a certain road speed (such as a cruise system), the speed should be specified in the test plan. Severity ratings and functional requirements are shown in the table below.
Vehicle test severity level