According to the rated power of the SMD resistor, calculate its highest rated voltage. In fact, it is not the case. The calculated maximum rated voltage can certainly ensure that the resistor will not be burnt out due to overheating during operation. However, when the resistance value R of the SMD resistor is large, the calculated voltage value will be very high. It is even higher than the value that the material and structural shape of the SMD resistor can withstand. For example, SMD resistor cannot be used directly in commercial circuits, even circuits with low power consumption like neon tube current limiting resistor in test pencils.
The value of voltage that this SMD resistor determined by its material and structural shape can withstand is called the highest rated voltage of this type of resistor.
The highest voltage rating of SMD resistor is different from traditional leaded resistor. The maximum rated voltage of traditional leaded resistor is not affected by the manufacturer, but is specified by the standard. For example, the maximum rated voltage of 1/4W carbon film resistor is 300V, and the maximum rated voltage of 1/6W carbon film resistor The highest rated voltage is 250V. However, the maximum rated voltage of SMD resistor varies slightly with different manufacturers and product types. Users are expected to pay attention to the manufacturer's product manuals when choosing.
For the same reason, it cannot represent the thick film SMD resistor produced by all manufacturers.
When the resistance value is not too high, it is not feasible to limit the voltage applied to the SMD resistor by the maximum rated voltage alone, because the actual power consumption of the resistor may exceed its rated power at this time. In other words, the SMD resistor should meet the two conditions of not exceeding the rated power and the rated maximum voltage at the same time.