We report a study of a compact, scalable up to TW peak power OPCPA with ∼1.2 ps pump pulses delivered from a Yb:YAG laser. Passive synchronization was ensured by using a small portion of the energy to generate a stable supercontinuum in the YAG, and the rest was directed to pump the three OPCPA stages. The temporal shape of the pump pulse was controlled by the degree of depletion of fundamental radiation in a two-cascade second harmonic converter. Under optimal conditions, the energy of amplified pulses reached ∼2.1 mJ with the support of a spectral bandwidth sufficient for a transform-limited pulse width of 8.6 fs.