Resistor features a resistance range of 1-500Ω
Designed for connection to the secondary-side of current sensing transformers, the Bulk Metal Foil Burden through-hole resistor has been released by Vishay Precision Group. Expanding the Vishay Foil Resistors product line, the device offers low TCR down to ±0.2ppm/°C from -55 to +125°C, 25°C ref., and load-life stability of ±0.005% after 2,000 hours at 0.1W at 70°C.
Current sensing transformers act as current sources and require a load. Like a voltage source, a current source should not be left open, as it would cause an infinite voltage. The resistor converts the current to a limited voltage. Typically, the Burden resistor will be used to discharge a capacitor when the circuit is no longer powered.
The device is designed to be connected to the output of the power device for the discharging of the bulk output filter capacitor when it is charged and connected to a large power source. Offering a low resistance, the Burden resistor prevents the influence of inrush current to the device in which the power unit is connected.
The device, which offers a maximum power rating of 0.6W at +70°C, features a resistance range of 1-500Ω, with tight resistance tolerance to ±0.005% (50ppm). Any conceivable ohmic value within this range, to six digits, is available with no additional cost or lead time effect. Available with both lead (Pb)-free and tin/lead alloy termination finishes, the resistor withstands ESD spikes to at least 25kV.
The Bulk Metal Foil Burden resistor is available now in both sample and production quantities.