In this paper, a novel and simple multi-bit quantizer based on the threshold inverter quantization (TIQ) approach is presented for use in sampled-data circuits. The key part is a front-end signal conditioning circuit with the aid of the interpolation technique that makes it possible to realize a rail-to-rail input range operation over the conventional threshold inverter-based quantizer circuits while maintaining the benefits of the TIQ structure without employing any analog-intensive circuits such as current sources or amplifiers, thus achieving a digital-compatible implementation. Simulation results in TSMC 90-nm CMOS technology at a power-supply voltage of 1[Formula: see text]V confirm the efficient performance of the proposed circuit.