Semiconductor apparatus capable of performing refresh control

1. A semiconductor apparatus comprising:

a current source, the current source increasing a current volume in compliance with a rise of a temperature:

an oscillation circuit, the oscillation circuit driven by the current from the current source and outputting a clock for refresh control;

a constant voltage source, the constant voltage source generating a constant voltage using the current source; and

a memory, the memory using the constant voltage generated by the constant voltage source as a reference voltage for a power supply circuit, the memory further performing the refresh in synchronization with the output clock of the oscillation circuit or the divided clock thereof.

2. A semiconductor apparatus comprising:

a current source, the current source increasing a current volume in compliance with a rise of a temperature; and

an oscillation circuit, the oscillation circuit driven by the current from the current source and outputting a clock for refresh control,

wherein the current source comprises a first diode, a second diode, at least one transistor, and at least one resistor, and

the current source generates a current in proportion to a voltage difference between a threshold voltage of the first diode and a threshold voltage of the second diode.

3. A semiconductor apparatus comprising:

a current source, the current source increasing a current volume in compliance with a rise of a temperature; and

an oscillation circuit, the oscillation circuit driven by the current from the current source and outputting a clock for refresh control,

wherein the current source is configured in the manner that,

a first terminal of a first transistor of a first conductivity type is connected to a power supply terminal,

a first terminal of a second transistor of the first conductivity type is connected to the power supply terminal,

a second terminal of the first transistor of the first conductivity type is connected to one end of a first resistor and one end of a second resistor,

a control terminal of the first transistor of the first conductivity type, a control terminal of the second transistor of the first conductivity type, and a second terminal of the second transistor of the first conductivity type are connected to one another,

another end of the first resistor is connected to one end of a third resistor and a first input terminal of an operational amplifier,

another end of the second resistor is connected to a second input terminal of the operational amplifier and an anode terminal of a first diode,

a cathode terminal of the first diode is connected to a ground potential,

another end of the third resistor is connected to an anode terminal of a second diode,

a cathode terminal of the second diode is connected to the ground potential,

the second terminal of the second transistor of the first conductivity type and a first terminal of a first transistor of a second conductivity type are connected to each other,

a control terminal of the first transistor of the second conductivity type is connected to an output terminal of the operational amplifier,

a second terminal of the first transistor of the second conductivity type is connected to the ground potential, and

the current source generates a current in proportion to a voltage difference between a threshold voltage of the first diode and a threshold voltage of the second diode.

4. A semiconductor apparatus as claimed in claim 1 , wherein the oscillation circuit constitutes a ring oscillator having an odd number of inverters serially connected.

5. A semiconductor apparatus as claimed in claim 1 , wherein the oscillation circuit constitutes a ring oscillator comprised of a 2n−1 number of transistors of a second conductivity type.

6. A semiconductor apparatus as claimed in claim 1 , wherein the oscillation circuit is constituted by a ring oscillator,

the ring oscillator is comprised of a 2n−1 number of transistors of a second conductivity type, wherein

first terminals of the plurality of transistors, which are first through (2n−2)th transistors, are respectively connected to control terminals of transistors each having a number larger by one,

a first terminal of the (2n−1)th transistor is connected to a control terminal of the first transistor, and

second terminals of all the transistors are connected to the ground potential.

7. A semiconductor apparatus as claimed in claim 1 , wherein the oscillation circuit comprises a function of terminating an oscillation thereof.

8. A semiconductor apparatus as claimed in claim 1 , wherein the oscillation circuit is capable of fluctuating a frequency.

9. A semiconductor apparatus as claimed in claim 1 ,

wherein the oscillation circuit and the current source respectively use different power supplies.

10. A semiconductor apparatus as claimed in claim 1 ,

wherein the current source is capable of terminating an operation thereof.

11. A semiconductor apparatus as claimed in claim 1 , wherein

the constant voltage of the constant voltage source is used as a reference potential for an internal circuit of the memory.

12. A semiconductor apparatus as claimed in claim 3 , wherein

in a system LSI comprising transistors having a plurality of insulation film thicknesses,

the first transistor of the second conductivity type of the current source connected to the output terminal of the operational amplifier and a transistor of the oscillation circuit connected to the first transistor have a same insulation film thickness.

13. A semiconductor apparatus as claimed in claim 3 , wherein

in a system LSI comprising transistors having a plurality of insulation film thicknesses,

the first transistor of the second conductivity type of the current source connected to the output terminal of the operational amplifier and a transistor of the oscillation circuit connected to the first transistor both have thick insulation films, and

any other transistor included in the current source and the oscillation circuit has a thin insulation film.

14. A semiconductor apparatus as claimed in claim 3 , wherein

in a system LSI comprising transistors having a plurality of insulation film thicknesses,

the current source and the oscillation circuit both uses transistors having thin insulation films.

15. A semiconductor apparatus as claimed in claim 2 , wherein

the diodes of the current source are formed in a same structure as a well structure of a memory cell region of a DRAM.

16. A semiconductor apparatus as claimed in claim 2 , wherein

the resistor of the current source is formed by means of a same wiring as a word line of a DRAM.

17. A semiconductor apparatus as claimed in claim 2 , wherein

the resistor of the current source is formed in a same step as a step for forming a word line of a DRAM.

18. A semiconductor apparatus as claimed in claim 3 , wherein

the oscillation circuit comprises current-mirror transistors having different sizes and is capable of fluctuating an oscillation frequency by changing a current value.

19. A semiconductor apparatus as claimed in claim 18 , wherein

fuses are used to switch over sizes of the current-mirror transistors.

20. A semiconductor apparatus as claimed in claim 1 , wherein

the constant voltage of the constant voltage source generating the constant voltage using the current source is used as a voltage source for other circuits.

21. A semiconductor apparatus comprising:

a current source, the current source increasing a current volume in compliance with a rise of a temperature; and

an oscillation circuit, the oscillation circuit driven by the current from the current source and outputting a clock for refresh control,

wherein in a system LSI,

the oscillation circuit is disposed inside a DRAM core, and the current source is disposed outside the DRAM core.