Patent ID: 6888384

Claim:
A power-on detector comprising: a current generation circuit having a first output terminal and a second output terminal and configured to produce a first current and a second current from the first output terminal and the second output terminal, respectively, the first current and the second current having a low degree of temperature dependency and being substantially equal to each other; a first load element connected between the first output terminal of the current generation circuit and a first potential supply source; a current mirror circuit having a first current path and a second current path, the first current path being connected to the second output terminal of the current generation circuit; a second load element connected between the second current path of the current mirror circuit and a second potential supply source; and a first comparator having a first input terminal connected to the first output terminal of the current generation circuit, and a second input terminal connected to a connection node between the second load element and the current mirror circuit, the first comparator making a comparison between (i) a first voltage obtained by causing the first current output from the first output terminal of the current generation circuit to flow to the first potential supply source by way of the first load element, and (ii) a second voltage obtained by causing a current flowing from the second potential supply circuit to the second current path of the current mirror circuit by way of the second load element, wherein power-on is detected when the second voltage becomes higher than the first voltage when a power supply is turned on.