In today’s world, pulses are common in electronic circuits. When these pulses encounter a resistor with high reactive components, they are distorted. If the resistor has high inductance, current through it will have a sluggish, slow rise time. The current will overshoot if the resistor has high capacitance. Either condition distorts the pulse’s waveform, potentially disabling the circuit’s function.
Wirewound resistor manufactures sometimes refer to Aryton-Perry windings when they talk about fast rise-time or high frequency response resistors. What are Aryton-perry windings? To make an Aryton-Peryy winding, you first wind a wire layer in one direction. After a layer of insulation, you wind the next wire layer in the opposite direction, with the turns crossing every 180 degrees. This reduces the undesirable reactance components of the winding: its inductance and capacitance.
The result? typical reactive values for these special designs are less than 1μh for a 500 ohm resistor, and less than 0.8pf capacitance for a 1 Megohm resistor. This provides a resistor with a fast rise-time of 20 nsec or less, while retaining the desirable tolerance, TCR and stability that are characteristic of wirewound resistors. So call us to get a quote on fast rise resistors.