The 7401 is a different member of the TTL family, as it consists of four NAND ports, but with the output transistor collectors open (This allows, with the use of external pull-up resistors, we can supply this step with up to 35 V and excite external loads of greater power. In the application of the figure, we have a circuit that converts rectangular signals of up to 1 MHz into triangular signals of the same frequency, but with a much greater amplitude, given precisely the output voltage of the stage. frequency: we can use 470 pF for frequencies up to 100 MHz, 270 pF for up to 200 kHz and 120 pF for up to 400 kHz. For frequencies up to 1 MHz the value will be 60 pF. The adjustments are linear, made in P1 and P2, to obtain a triangular output with no distortion with the incoming TTL signal. The linearity of the circuit is excellent, reaching 1% if an adjustment is made in place.
