Many computing systems (for example, portable or mobile systems) need to maintain a low power consumption. For example, net-zero energy computing devices, wearable devices, or internet of things (IoT) devices, among others, require low power consumption. Net-zero energy computing devices are experiencing a paradigm shift toward extremely low power consumption. In particular, reduction of standby power can be an important goal since some devices may spend most of their time in a standby mode. In order to maintain a low overhead, it is key for some devices to transition very quickly between low power standby modes and active modes. However, some circuits (for example, some analog circuits) that are designed for very low power consumption may exhibit low speeds. Reference voltage generators that define reference voltages for multiple supply rails of an integrated circuit (IC) such as an SoC (system on a chip) can exhibit low speeds. Reference voltages may need to be maintained with very low power consumption while in a standby state, but may also need to quickly change (for example, when an SoC transitions to an active state and requires higher supply voltages).
In some cases, the same numbers are used throughout the disclosure and the figures to reference like components and features. In some cases, numbers in the 100 series refer to features originally found in FIG. 1; numbers in the 200 series refer to features originally found in FIG. 2; and so on.