Power oscillator apparatus with transformer-based power combining

An oscillator circuit includes first and second oscillators arranged in a series configuration between a supply voltage node and a reference voltage node. The first and second oscillators are configured to receive a synchronizing signal for controlling synchronization in frequency and phase. An electromagnetic network provided to couple the first and the second oscillators includes a transformer with a primary circuit and a secondary circuit. The primary circuit includes a first portion coupled to the first oscillator and second portion coupled to the second oscillator. The first and second portions are connected by a circuit element for reuse of current between the first and second oscillators. The oscillator circuit is fabricated as an integrated circuit device wherein the electromagnetic network is formed in metallization layers of the device. The secondary circuit generates an output power combining power provided from the first and second portions of the primary circuit.