Relay Stepped Attenuator Schematic

Relay attenuator shield has been designed for audio attenuation after piano dac output by 1db step size its compact and simple circuit just 6 tiny relays implement a 64 step logarithmic stereo attenuation the 64 steps of 1 0db together span a 63db audio attenuation range.

Relay stepped attenuator schematic.

The differential amplifier removes common mode interference while maximizing the use of the voltage headroom in the 256 step attenuator. A stepwise volume control is implemented with a set of tiny relays and resistors. It uses high quality miniature latching relays and precision discrete resistors to achieve a level of performance unattainable with conventional potentiometers or mechanical switch based rotary stepped attenuators. The differential amplifier delivers a voltage balanced signal to the attenuator stage.

Attenuator that provides good performance yet can be built with a few basic tools 1 this unit is designed for use in 50 ω line provides a total attenuation of 71 db in 1 db steps offers respectable accuracy and insertion loss through 225 mhz. Overview δ1 delta 1 is a high end stereo stepped attenuator implemented in a r 2r resistor laddertopology. δ1 v1 0 boards are now available at amb audio shop. A stepped attenuator also has very good channel matching but whereas even the expensive dact only gets you 24 steps typically with 2db between them 128 or even 256 steps of 0 5db each are quite easily achieved with relays.

It is very unusual to see a stepped attenuator with more than 64 steps. By avoiding any active. 256 steps 0 5 db step size.