An EDN design idea presents a pushbutton interface for a digital potentiometer that reacts on press rather than on release. Each tap of the UP button increments the DPOT by one count, while the DOWN button decrements it by one count.
The circuit centers on a clean clock pulse derived from a noisy mechanical switch transition. A push on either button drives U1a pin 3 high. Contact bounce is suppressed by an R3C1 network with an approximate 5 ms time constant, and a Schmitt-trigger inverter, U1d, converts that filtered signal into a single clean low-going edge for the potentiometer clock input.
The direction input determines whether that edge increments or decrements the wiper position. When the UP button is pressed and DOWN is not active, U2 steps up. When the DOWN button is pressed, the same clock transition steps the wiper down. The timing discussion in the source notes that the U/D input only needs to be valid during a short setup window before the falling clock edge.
The article also notes that this approach slightly reduces part count compared with the referenced alternative, although the author treats that as a secondary point. The main technical point is the interface behavior: the circuit aligns the digital potentiometer with the user’s expectation that a button press should take effect immediately, while still filtering bounce enough to generate a single deterministic step.