High accuracy, compact on-chip temperature sensor

Embodiments of a temperature sensing apparatus are disclosed. The apparatus may include a voltage generator and circuitry. The voltage generator may generate a first voltage level and a second voltage level dependent on an operating temperature. In response to a given change in the operating temperature, the first and second voltage levels may change, with the second voltage level changing by a different amount than the first voltage level. The voltage generator may generate a third voltage level. The circuitry may measure the first voltage level, the second voltage level, and the third voltage level, and may calculate the operating temperature dependent on a ratio of a difference between the first voltage level and the second voltage level and the third voltage level.