Voltage detection circuit

1. A voltage detection circuit comprising:

a reference voltage and current supply configured to generate a reference voltage and a reference current;

a first switching element having a first gate which receives the reference voltage or a voltage generated by a voltage output circuit based on the reference voltage, configured to shift from an off-state to an on-state when the applied voltage at the first gate is higher than a predetermined first threshold voltage, the reference voltage or the voltage generated by a voltage output circuit based on the reference voltage being generated without utilizing any comparator;

a current mirror circuit allowing a current corresponding to the reference current to flow through the first switching element in the on-state;

a capacitive element coupled in series to the current mirror circuit, and charged with the current flowing through the first switching element; and

an output circuit configured to output an enable signal activated based on a terminal voltage of the capacitive element.

2. The voltage detection circuit of claim 1 , wherein the first switching element is an N-channel MOS transistor.

3. The voltage detection circuit of claim 1 , further comprising:

a discharge circuit configured to discharge the capacitive element.

4. The voltage detection circuit of claim 3 , wherein

the discharge circuit includes a P-channel MOS transistor arranged in parallel to the capacitive element, and

a gate and a source of the P-channel MOS transistor are coupled together to discharge the capacitive element through a body diode of the P-channel MOS transistor.

5. The voltage detection circuit of claim 1 , wherein the output circuit includes an inverter configured to receive the terminal voltage of the capacitive element at an input terminal.

6. The voltage detection circuit of claim 1 , further comprising:

a voltage output circuit configured to generate an internal voltage from the reference voltage; and

a second switching element having a second gate which receives a voltage generated by the voltage output circuit based on the reference voltage, configured to shift from an off-state to an on-state when the applied voltage at the second gate is higher than a predetermined second threshold voltage,

wherein the voltage output circuit supply the internal voltage to the second switching element.

7. The voltage detection circuit of claim 6 , wherein the voltage output circuit includes a resistance divider circuit for adjusting a voltage to be supplied to the second switching element.

8. The voltage detection circuit of claim 6 , wherein the second switching element is an N-channel MOS transistor configured to receive a voltage supplied from the voltage output circuit at a gate.

9. An electronic circuit determining activation of the reference voltage and current supply based on an output of the voltage detection circuit of claim 1 .

10. An electronic circuit determining activation of the reference voltage and current supply based on an output of the voltage detection circuit of claim 6 .

11. The voltage detection circuit of claim 6 , wherein the second switching element is an N-channel MOS transistor.

12. The voltage detection circuit of claim 6 , further comprising:

a discharge circuit configured to discharge the capacitive element.

13. The voltage detection circuit of claim 12 , wherein

the discharge circuit includes a P-channel MOS transistor arranged in parallel to the capacitive element, and

a gate and a source of the P-channel MOS transistor are coupled together to discharge the capacitive element through a body diode of the P-channel MOS transistor.

14. The voltage detection circuit of claim 6 , wherein the output circuit includes an inverter configured to receive the terminal voltage of the capacitive element at an input terminal.

15. The voltage detection circuit of claim 6 , wherein the second gate of the second switching element receives the reference voltage without any comparator.