Takaab 3HWR - Triple Passive Half Wave Rectifier

Passive, diode rectification. Each of the three gates has one input and two outputs. Assuming an AC signal at the input, the first (+ve) out will output only the positive part of the original signal. Conversely the -ve out will output any negative voltage parts of the signal. Note that there is a drop of approximately 0.3V.

You can actually use the 3HWR in reverse. Using the OUTs as INs and the IN as an OUT will rectify both signals then sum them together. In this use case note that the +ve and -ve labels are reversed so the +ve IN will send the negative part of the signal to be summed and vice versa.