Passive Attenuating Overview

Passive Debilitator is a fully resistant network used to weaken the signal level of a transmission line, improving impedance matching and making passive debilitators the opposite of amplifiers. Passive Attenuators are electrically connected between the weld feed and the load, with a fixed amount of induced weakening. The connected debilitating section can provide constant weakening, impedance compatibility or insulation between welding and load. Since it has only resistant elements in a passive attenuator design, the weakened signal is not affected by distortion or phase shift. Passive attenuating designs can be fixed, gradual or variable; Constant attenuators are known as "pad debilitators" with widely used attenuation networks ranging from 1dB to 20dB. The amount of weakening offered by the debilitating pad is determined by the voltage ratio between the input source signal and the output load signal, which is expressed in decibels. The ratio between the input signal (Vin) and the output signal (Vout) is given as follows: This voltage ratio can also be derived from weakening in decibels. A factor known as the "K factor" can be used in the calculation of debilitating resistance elements. Tables that give the value "K" can be produced, as shown, because the "K" factor corresponds to a certain amount of weakening in decibels. k factor

"K" Factor Tables for Debilitating Loss

dB Loss0.
K value1.05931.12201.25891.41251.99532.37142.81843.1623
dB Loss12.
K value3.98117.943315.84931.62363.096251.191000105

A voltage weakening of 6dB will be 10^(6/20) = 1.9953. Passive Attenuators can be symmetrical or asymmetrical in the form and can be of a balanced or unstable type. Common passive attenuating circuits include the type "T-type", "Pi-type" and "Bridged-T", as shown below.

L-pad Attenuator Design

The L-pad Debilitating is the simplest debilitating design consisting of only two resistant elements and is more commonly known as the voltage dividing circuit. L-pad debilitating is an unstable asymmetric debilitating circuit that can only match impedance in one direction. The balanced equivalent of "L-pad Debilitator" is called U-pad debilitator.

T-pad Debilitating Design

The T-pad Debilitator is referred to by this name because its configuration resembles the letter "T". "T-pad Debilitator" is a symmetrical attenuator that can be used for slimming between equal impedances or impedance matching between unequal impedances. When the weight loss is high, the parallel shunt arm impedance shrinks. The balanced equivalent of the T-pad debilitator is called the H-pad debilitator.

BridgeD T-pad Debilitating Design

The Bridged-T Debilitator is a variation in the standard T-pad design with an additional resistant element that creates a bridged network between two series of resistors, and takes its name from the fact that the input sources signal creates a "bridge" between the T- "Bridged-T Attenuator" is a symmetrical, fully resistant attenuator that can be easily used as a variable attenuator or a replaceable debilitator. It is also possible to create a balanced version of the Bridged-T debilitating circuit.

Pi-pad Attenuating Design

Pi-pad is called Debilitating because its resistant configuration is similar to the Greek letter "π" (pi). "Pi-pad Debilitator" is the most common symmetrical passive attenuator, which can be used between equal impedances or between unequal impedances. A single Pi-pad debilitator can achieve much higher slimming levels compared to the equivalent T-pad debilitator, and when the weight loss is high, the serial arm impedance is large. The balanced equivalent of pi-pad debilitator is called O-pad debilitating.