What is claimed is:
1. An air conditioner for a vehicle, comprising:
a compressor for compressing and discharging refrigerant;
an exterior heat exchanger for cooling refrigerant discharged from the compressor in a cooling mode;
an air conditioning case in which air flows toward a passenger compartment;
an interior heat exchanger for cooling air by absorbing heat from air in the cooling mode, the interior heat exchanger being disposed in the air conditioning case to heat air in a heating mode where the refrigerant discharged from the compressor is introduced into the interior heat exchanger through a hot-gas heater cycle while bypassing the exterior heat exchanger;
a switching member disposed to selectively switch one of the cooling mode and the heating mode;
an accumulator for separating refrigerant into gas refrigerant and liquid refrigerant and for storing the separated liquid refrigerant therein, the accumulator being disposed between an outlet of the interior heat exchanger and a suction port of the compressor, wherein:
the accumulator includes a heating device for heating the liquid refrigerant stored in the accumulator.
2. The air conditioner according to claim 1, further comprising
a heating heat exchanger for heating air using hot water from an engine of the vehicle as a heating source, the heating heat exchanger being disposed in the air conditioning case at a downstream air side of the interior heat exchanger,
wherein the compressor is driven by the engine.
3. The air conditioner according to claim 2, wherein the heating device is a hot water pipe into which hot water from the engine is circulated.
4. The air conditioner according to claim 3, wherein the hot water pipe is disposed to heat an outer peripheral surface of the accumulator at a position where the liquid refrigerant is stored.
5. The air conditioner according to claim 1, wherein:
the accumulator includes a tank body in which the liquid refrigerant is stored; and
the heating device is provided to heat an outer peripheral surface of the tank body at a position where the separated liquid refrigerant is stored.
6. The air conditioner according to claim 5, wherein:
the heating device is provided to heat the outer peripheral surface of the tank body and a bottom outer surface of the tank body.
7. The air conditioner according to claim 5, wherein:
the tank body has a cylindrical outer shape.
8. The air conditioner according to claim 1, wherein the heating device is an electric heater.
9. The air conditioner according to claim 8, wherein:
the electric heater includes a heater body having a thin plate shape, and a film member covering the heater body; and
the heater body has an electrical resistance material.
10. The air conditioner according to claim 9, wherein:
the accumulator includes a tank body in which the separated liquid refrigerant is stored;
the tank body has a cylindrical outer peripheral surface; and
the electric heater is cylindrically bent to be attached to the outer peripheral surface of the tank body at a lower side position.
11. The air conditioner according to claim 8, further comprising:
a pressure detection device for detecting pressure of refrigerant at a high-pressure side of the hot-gas heater cycle in the heating mode; and
a heater control unit for controlling an operation state of the electric heater based on the pressure detected by the pressure detection device so that the pressure of refrigerant at the high-pressure side becomes higher than a predetermined pressure.
12. The air conditioner according to claim 1, wherein the accumulator has a tank body in which the separated liquid refrigerant is stored, the air conditioner further comprising:
a surface temperature detection device for detecting an outer surface temperature of the tank body, wherein:
when the temperature detected by the surface temperature detecting device is lower than a predetermined temperature, the heating device heats the liquid refrigerant in the tank body of the accumulator.
13. The air conditioner according to claim 2, further comprising
a water temperature detecting device for detecting temperature of water flowing from the engine to the heating heat exchanger, wherein:
when the temperature detected by the water temperature sensor is lower than a predetermined temperature, the heating device heats the liquid refrigerant in the accumulator.
14. The air conditioner according to claim 1, further comprising
an air temperature detecting device for detecting at least one of an air temperature immediately blown from the interior heat exchanger and an air temperature in the passenger compartment, in the heating mode,
when the air temperature detected by the air temperature detecting device is lower than a predetermined temperature, the heating device heats the liquid refrigerant in the accumulator.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A DRAM semiconductor memory device comprising:
a plurality of memory cells, each memory cell including a selection transistor and a storage capacitor, the plurality of memory cells being arranged in a memory cell array with bit lines and word lines, wherein a drain region of each selection transistor is connected to a respective bit line and a gate of each selection transistor is connected to a respective word line;
a plurality of bit lines including at least a pair of first and second bit lines, wherein each of the first and second bit lines includes a memory cell connected to the bit line and a further memory cell connected to the bit line;
a plurality of sense amplifiers including a sense amplifier being connected to the pair of first and second bit lines; and
a driving circuit device connected to the gate of each further memory cell connected to the first and second bit lines, wherein the driving circuit is configured to simultaneously switch on the gates of the further memory cells in response to initiating a precharge operation for charging the pair of first and second bit lines to an equalization voltage.
2. The DRAM semiconductor memory device of claim 1, wherein, during a read operation of the memory cell connected to one of the pair of first and second bit lines, the driving circuit device is configured to turn on the gate of the further memory cell that is connected to the other of the pair of first and second bit lines.
3. The DRAM semiconductor memory device of claim 1, further comprising:
a bit line equalization circuit device that connects a variable voltage source to the pair of first and second bit lines and short-circuits the pair of first and second bit lines during the precharge operation, wherein a resistance of the connection between the voltage source and the pair of first and second bit lines is a plurality of orders of magnitude greater than the resistance between the short-circuited pair of first and second bit lines.
4. The DRAM semiconductor memory device of claim 3, wherein the variable voltage source comprises laser fuses to set an output voltage.
5. The DRAM semiconductor memory device of claim 4, further comprising:
a charge circuit device that charges the storage capacitors of the further memory cells to a specific voltage.
6. The DRAM semiconductor memory device of claim 5, wherein the charge circuit device includes a variable voltage source to provide the specific voltage.
7. The DRAM semiconductor memory device of claim 1, wherein the further memory cells are arranged in an edge region of the memory cell array.
8. The DRAM semiconductor memory device of claim 1, wherein the further memory cells comprise redundant DRAM memory cells.
9. The DRAM semiconductor memory device of claim 1, further comprising:
two lines running parallel to adjacent sense amplifiers, wherein one of the two lines drives the gate of the further memory cell connected to the first bit line and the other of the two lines drives the gate of the further memory cell connected to the second bit line.
10. An electric device comprising the DRAM semiconductor device of claim 1.
11. A method for increasing the reading accuracy of a DRAM memory cell comprising:
providing a memory cell array that comprises bit lines, word lines, memory cells, with each memory cell including a selection transistor and a storage capacitor, the drain regions of the selection transistors being connected to the bit lines and the gates of the selection transistors being connected to the word lines, and a plurality of sense amplifiers connected to respective pairs of bit lines, where each pair of bit lines includes a first bit line and a second bit line, with a memory cell and a further memory cell being connected to each of the first and second bit lines of each pair of bit lines;
charging the storage capacitors of the further memory cells prior to a precharge operation of the pairs of bit lines; and
switching on the gates of the further memory cells connected to a selected pair of first and second bit lines in response to a precharge operation for charging the first and second bit lines of the selected pair to an equalization voltage that is different from half of a bit line high voltage level value.
12. The method of claim 11, wherein, during the precharge operation, the first and second bit lines of the selected pair are connected to a variable voltage source to set an output voltage, and the first and second bit lines of the selected pair are short-circuited with one another, such that a resistance of the connection between the variable voltage source and the first and second bit lines of the selected pair is a plurality of orders of magnitude greater than the resistance between the short-circuited first and second bit lines of the selected pair.
13. The method of claim 12, wherein, during a test mode of the DRAM in which the variable voltage source is deactivated, the variable voltage source is set to the equalization voltage by measuring the equalization voltage at an equalization voltage pad, and the variable voltage source is set to the measured equalization voltage.
14. The method of claim 12, wherein the variable voltage source is set to the equalization voltage via laser fuses.
15. The method of claim 11, wherein the further memory cells are selected from memory cells in an edge region of the memory cell array.
16. The method of claim 11, wherein the further memory cells comprise redundant memory cells.
17. The method of claim 11, wherein a plurality of further memory cells are connected to each bit line, and the further memory cells connected to each bit line are jointly driven.
18. A method for increasing the reading accuracy of a DRAM memory cell in a memory cell array comprising:
providing a memory cell array that comprises bit lines, word lines, memory cells, with each memory cell including a selection transistor and a storage capacitor, the drain regions of the selection transistors being connected to the bit lines and the gates of the selection transistors being connected to the word lines, and a plurality of sense amplifiers connected to respective pairs of bit lines, where each pair of bit lines includes a first bit line and a second bit line, with a memory cell and a further memory cell being connected to each of the first and second bit lines of each pair of bit lines;
switching on the gates of the further memory cells connected to a selected pair of first and second bit lines in response to a precharge operation for charging the first and second bit lines of the selected pair to an equalization voltage; and
in response to a read operation of a memory cell connected to the first bit line of the selected pair of first and second bit lines, switching on the gate of the further memory cell connected to the second bit line of the selected pair of first and second bit lines.
19. The method of claim 18, wherein the further memory cells comprise memory cells located in an edge region of the memory cell array.
20. The method of claim 18, wherein the further memory cells comprise redundant memory cells.
21. The method of claim 18, wherein a plurality of further memory cells are connected to each bit line, and the further memory cells connected to each bit line are jointly driven.