In 2011, an OEM manufacturer of critical aviation equipment contacted TFT regarding a desire to replace their current wire wound bleed off resistor with a lighter more compact thick film resistor. The customer’s product incorporates a high power capacitor used in the operation of the plane and as a safety measure there needs to be the option to drain the power stored in the capacitor should anything in the system fail and need to be shut down. The capacitor stores quite a lot of power and when discharging does so in a series of high frequency/high voltage pulses. The resistor had to be capable of discharging the power without damage multiple times and do so in a volume of only about 3 cm3 .
Working with the customer, TFT developed several design iterations until all the criteria were met and the part went into production.