  In this paper the QCD phase diagram is obtained by the crossing of two
effective models: the MIT bag based models are used to describe quark matter
and QHD type models to describe hadronic matter, being the use of the former
something new to this kind of approach and the latter used with improved
parameterizations as compared with previous calculations. We use the Gibbs'
conditions to establish the crossing points of the pressure in function of the
chemical potential obtained in both phases. We first analyze two-flavour
symmetric matter constrained to both the freeze-out and the liquid-gas phase
transition at the hadronic phase. Later we analyse the results for
$\beta$-stable and charge neutral stellar matter and compare two different
prescriptions: one that assumes flavour conservation, so that the quark phase
is completely determined from the hadronic phase, a prescription never applied
to finite temperatures before, and the other based on the Maxwell construction,
where the quark phase is also $\beta$-stable. At the end, we compute the latent
heat to find a signature of the critical end point.
