Abstract: A thin film power coupler, in particular, a 3 dB and 90 degree power divider, is fabricated of lumped circuit elements. The main characteristics of the coupler is in having achieved the coupled inductances by mutual induction. Such an achievement has been obtained with 2 microstrip lines facing each other and wrapped in a square shaped spiral. Another important characteristic of the power coupler is the presence of a capacitor in the circuit which joins the two branches of the coupler, with sufficient tolerance to obtain the wanted coupling and to recover possible tolerances incurred by manufacturing the thin film inductors.