Transition Minimized Differential Signaling (TMDS) is a technology for transmitting high-speed serial data and is used by the DVI and HDMI video interfaces.

The transmitter incorporates an advanced coding algorithm which has reduced electromagnetic interference over copper cables and enables robust clock recovery at the receiver to achieve high skew tolerance for driving longer cable lengths as well as shorter low cost cables.

The encoding uses 8B/10B encoding, which is a two-stage process resulting in ten bits being used to represent eight bits. In the first, each bit is either XOR or XNOR transformed against the previous bit, although the first bit is not transformed at all. The system chooses between XOR and XNOR by determining which will result in the fewest transitions, and a ninth bit is added to show which was used. In the second stage, all nine bits are optionally inverted to even out the balance of ones and zeroes and therefore the overall DC level. A tenth bit is added to indicate whether the inversion took place.

TMDS was developed by Silicon Image Inc. as a member of the Digital Display Working Group.

Computer and telecommunication standards

Transition Minimized Differential Signaling