The X- and gamma-ray telescope ECLAIRs onboard the future mission for gamma-ray burst studies SVOM (Space-based multi-band astronomical Variable Objects Monitor) is foreseen to operate in orbit from 2014 on. ECLAIRs will provide fast and accurate GRB triggers to other onboard telescopes, as well as to the whole GRB community, in particular ground-based follow-up telescopes. With its very low energy threshold ECLAIRs is particularly well suited for the detection of highly redshifted GRB. ECLAIRs consists of a X- and gamma-ray imaging camera (CXG) observing in a field of view of 2 sr. The CXG is a 2D-coded mask imager with a 1024 cm2 detection plane made of 80 x 80 CdTe pixels, sensitive from 4 keV to 250 keV, with imaging capabilities up to about 50 keV and a localization accuracy better than 10 arcmin. ECLAIRs includes also a triggering electronics which uses the CXG data and detects GRB as countrate increases or the appearance of a new source in cyclic sky images. GRB alerts are transmitted to observers within tens of seconds via a VHF network and all detected photons are available hours later. In this talk we present the lastest ECLAIRs concepts, with emphasis on the expected performances.