Vishay Customized PHP Series Chip Resistor

Challenge

When an existing resistor supplier was temporarily shut down and unable to manufacture the parts required during the pandemic, these engineers came to Vishay for customized products. The case sizes, resistance values, and power ratings of the devices were not common values and were unavailable in a standard series.

Vishay was asked to design a 1W resistor in the 2506 case size with two resistance values below 10Ω.

Solution

The thin film PHP series was electrically similar to the requested solution in terms of material specifications and, therefore, some areas of electrical performance. These chips were available in the 2512 case size with a 25W rating and a resistance range from 10Ω to 30kΩ. By mechanically altering the substrate and reducing the case size width by 50%, these chips immediately met the 2506 case size requirement, and the part could easily achieve a power rating of 1W.

Because of the unique resistance values required, sputtering additional material onto the substrate reduced the resistance values, and testing helped to establish the process required to achieve the required low ohmic values. All of these customizations were completed in under three weeks.

Benefit

Once these customized products were delivered to the engineers, they were able to restart production of their ventilator products and shipments to hospitals for COVID-19 patients.