Resistors and other passive electronic components can often become difficult to source or obsolete at short notice causing delays to production schedules, upsetting important customers and wasting resources. As many manufacturers may be chasing the same solution the correct component can be both difficult and expensive to source. In some cases an attempt may be made to purchase residual stock from distribution or component brokers but this can lead to issues with quality or counterfeit components.
One alternative is to work with a specialist manufacturer to produce a form fit and function replacement for the original device. The key to success is a full datasheet and detailed quality specification on the original device and an open and flexible approach. Both the customer and supplier must agree what parameters (mechanical, electrical and quality) are essential and where compromises may be made. The impact of any design changes on re-qualification requirements (or not) must always be considered carefully.
Time is inevitably wasted evaluating a wide range of potential obsolescence solutions so when the manufactured replacement option is chosen time is always limited. As obsolescence issues are an unexpected expense available project funds tend to be minimal so a low cost, fast solution is often required.
The Advantages Of Thick Film Resistors
Thick film resistors are relatively cheap to tool and their simple construction means they can be designed and manufactured on relatively short timescales at a reasonable price. If a specialist manufacturer is chosen obsolescence solutions can often be made available in the low to medium volumes required to continue system production until a long-term solution can be found.
Thick film technology is robust and resistor trimming delivers a wide range of resistor values and tolerances. The material has excellent thermal and electrical properties so it may be used for a wide range of applications from power applications to precision sensors. The construction of thick film devices ensures they may be used in a variety of harsh environments and deliver long-term reliability.
Thick film substrates deliver the option of either solderable or wire bondable connections ensuring they may be used in a wide range of applications. A variety of leadframe options is also available so devices may be manufactured to fit the original device footprint even if the body size or aspect ratio is slightly different to the original.
Design and manufacture of a new thick film resistor device can often deliver a solution with a specification and footprint that matches the obsolete device at an acceptable price.