Interpolating ring VCO with V-to-f linearity compensation

The nonlinearity of interpolating ring voltage controlled oscillators is inherent because the interpolation is linear in delay. Linearity can be restored with a correction based on the predictable curvature of an unbalanced Gilbert translinear cell. Experimental results show V-to-f linearity better than 0.2% over a ±10% frequency range about 155 MHz