Power tracking circuit and semiconductor apparatus including the same

A power tracking circuit comprises a voltage sensing unit, a first pulse generating unit, a first delay unit, a set signal generating unit, a second pulse generating unit, a second delay unit, a reset signal generating unit and a latch unit. The voltage sensing unit generates a sensing signal by sensing a level of an external voltage on the basis of a reference voltage. The first pulse generating unit generates a first pulse signal when the level of the sensing signal is transferred from a first level to a second level. The first delay unit delays the first pulse signal for a first certain time. The set signal generating unit activates a set signal in case that the sensing signal maintains the second level at the activation timing of the delayed first pulse signal. The second pulse generating unit generates a second pulse signal when the level of the sensing signal is transferred from the second level to the first level. The second delay unit delays the second pulse signal for a second certain time. The reset signal generating unit activates a reset signal in case that the sensing signal maintains the first level at the activation timing of the delayed second pulse signal. The latch unit activates a power tracking signal in response to the set signal and deactivates the power tracking signal in response to the reset signal. [Reference numerals] (1) Voltage sensing unit;(2_1) First pulse generating unit;(2_2) Second pulse generating unit;(3_1) First delay unit;(3_2) Second delay unit;(4_1) Set signal generating unit;(4_2) Reset signal generating unit;(5) Latch unit