Temperature sensing device and electric device including the same
A temperature sensing device includes a current generator to generate a variable current that varies based on temperature, a charge circuit to accumulate charges based on the variable current, and a count logic circuit to generate a count value synchronized to a clock, and to output the count value as temperature data based on a charged voltage of the charge circuit and a reference voltage.
1. A temperature sensing device comprising:
a current generator configured to generate a variable current, the variable current varies based on a sensed temperature;
a charge circuit configured to accumulate charges based on the variable current; and
a count logic circuit including,
a counter configured to,
activate with the charge circuit, and
generate a count value synchronized to a clock,
a comparator configured to generate a control signal if an accumulated charge voltage, associated with the variable current, is equal to a reference voltage, and
a latch configured to,
store the count value, in response to the control signal, and
output the count value as temperature data based on the accumulated charge voltage of the charge circuit and the reference voltage.
2. The temperature sensing device of claim 1 , wherein the count logic circuit is configured to,
compare the charge voltage to the reference voltage, and
output the temperature data if the charg voltage reaches the reference voltage.
3. The temperature sensing device of claim 1 , wherein the current generator includes a diode, and generates the variable current based on an amount of current flowing through the diode.
4. The temperature sensing device of claim 1 , wherein the current generator generates the variable current proportional to the sensed temperature.
5. The temperature sensing device of claim 1 , wherein the current generator comprises:
a current mirror configured to provide the variable current via first and second terminals;
a diode electrically connected between the first terminal of the current mirror and a ground terminal;
a resistance circuit electrically connected to the second terminal of the current mirror; and
a plurality of diodes connected to the resistance circuit and the ground terminal.
6. The temperature sensing device of claim 5 , wherein the resistance circuit is a switched capacitor operating in response to the clock and an inverse signal of the clock.
7. The temperature sensing device of claim 1 , wherein the charge circuit comprises:
a capacitor charged by the variable current in response to an enabling signal and reset in response to an inverse signal of the enabling signal.
8. The temperature sensing device of claim 1 , wherein a multiplication of the sensed temperature and the temperature data is a constant if the reference voltage is regular.
9. The temperature sensing device of claim 1 , wherein a multiplication of the sensed temperature and the temperature data varies with the reference voltage.
10. An electronic system comprising:
a temperature sensing device configured to detect a temperature, the temperature sensing device including,
a current generator configured to generate a variable current, the variable current varies by a sensed temperature,
a charge circuit configured to accumulate charges based on the variable current, and
a count logic circuit including,
a counter configured to,
activate with the charge circuit, and
generate a count value synchronized to a clock,
a comparator configured to generate a control signal if an accumulated charge voltage, associated with the variable current, is equal to a reference voltage, and
a latch configured to, P 4 store the count value, in response to the control signal, and
output the count value as temperature data based on the accumulated charge voltage of the charge circuit and the reference voltage; and
a processor configured to control the electronic system based on the sensed temperature.
11. The electronic system of claim 10 , wherein a multiplication of the sensed temperature and the temperature data is a constant if the reference voltage is regular.
12. The electronic system of claim 11 , wherein the processor stores a multiplication of a calibrated temperature and temperature data of the calibrated temperature as a reference value.
13. The electronic system of claim 12 , wherein the processor determines the temperature based on the temperature data and the reference value.
14. The electronic system of claim 10 , wherein a multiplication of the sensed temperature and the temperature data varies with the reference voltage.
15. The electronic system of claim 14 , wherein the processor stores reference values used for compensating variations of the reference voltage, based on multiplications of a calibrated temperature and temperature data of the calibrated temperature.
16. The electronic system of claim 15 , wherein the processor determines the sensed temperature based on the temperature data, the temperature data corresponding to the reference values.
17. The electronic system of claim 10 , wherein the temperature sensing device and the processor are integrated in a single semiconductor device.
18. The electronic system of claim 10 , wherein the processor communicates with an external host.