This is Purandara Dasa. The identification is based on Tamboori (right hand) and Manjira or clappers in his left hand (See the side view).

Purandara Dasa is a historical figure born in the late fifteenth century. Purandara Dasa is a saint, a Haridasa (A great devotee of Lord Krishna), a reformer, a composer and singer of Carnatic music.

Here Purandara Dasa is sitting erect in Ardhapadmasana and is completely engaged in his singing.  He is seated on a rectangular peetha.

A much loved and revered idol. The idol is about 6 cm in height.

This idol is possibly from North Deccan, see the epaulettes (Side and back views). Going by the ritual wear, this idol probably dates prior to the nineteenth century.