Semiconductor memory having a short effective word line cycle time and method for reading data from a semiconductor memory of this type

1. A method for reading data from a semiconductor memory comprising at least one first memory bank and at least a first and second shadow memory banks which are each designed to store a multiplicity of binary data items, wherein the same data are stored in the first memory bank and the first and second shadow memory banks, the method comprising:

receiving a command for reading data which are to be read from the at least one first memory bank;

responsive to the received command, determining whether the at least one first memory bank is in an open memory bank state utilizing a state checking device of a control device of the semiconductor memory, wherein the open memory bank state is a memory state which does not allow the data to be read from an open word line of the first memory bank until a next word line cycle, wherein the first memory bank is accessible using an address input interface in the semiconductor memory, wherein the first and second shadow memory banks are accessible using the control device and not the address input interface;

upon determining that the first memory bank is in the open memory bank state, determining whether the first shadow memory bank is in the open memory bank state utilizing the state check device;

upon determining that the first shadow memory bank is in the open memory bank state, reading the data from the second shadow memory bank; and

upon determining that the first memory bank is not in the open memory bank state, reading the data from the at least one first memory bank,

wherein during a step of writing data to the at least one first memory bank, the data are written by the control device to the first and second shadow memory banks at the same time.

2. The method of claim 1 , wherein the step of checking whether the at least one first memory bank or the first shadow memory bank is in an open memory bank state comprises an operation of comparing a period of time which has elapsed since a previous read command was last applied to a respective memory bank to a minimum word line cycle time t RC of the respective memory bank.

3. The method of claim 1 , wherein the semiconductor memory comprises a reduced latency dynamic random access memory (RLDRAM).

4. A semiconductor memory, comprising:

a first memory bank and first and second shadow memory banks for storing binary data, the same data as in the first memory bank being stored in the first and second shadow memory banks;

a control device of the semiconductor memory device which is signal-connected to the memory banks, the control device having a state checking device configured to determine whether the first memory bank is in an open memory bank state during which an open word line of the first memory bank must be closed prior to reading further data from the first memory bank;

wherein the first memory bank is accessible using an address input interface in the semiconductor memory, wherein the first and second shadow memory banks are accessible using the control device and not the address input interface,

wherein, in response to a read command received by the semiconductor memory for reading data which are to be read from the first memory bank, the control device is configured to utilize the state checking device to check whether the first memory bank is in the open memory bank state; and

if the first memory bank is in the open memory bank state, determine whether the first shadow memory bank is in the open memory bank state,

if the first shadow memory bank is in the open memory bank state, apply the read command to the second shadow memory bank, and

if the first memory bank is not in the open memory bank state, apply the read command to the first memory bank,

wherein, when writing data to the first memory bank, the control device is configured to write the same data to the first and second shadow memory banks at the same time.

5. The semiconductor memory of claim 4 , wherein, when determining whether the first memory bank or the first shadow memory bank is in an open memory bank state, the state checking device is configured to compare a period of time that has elapsed since a previous read command was last applied to a respective memory bank to a minimum word line cycle time t RC of the respective memory bank.

6. The semiconductor memory of claim 4 , wherein the semiconductor memory comprises a reduced latency dynamic random access memory (RLDRAM).

7. A memory apparatus, comprising:

a plurality of first memory banks;

a plurality of shadow memory banks, wherein each first memory bank is associated with first and second shadow memory banks, each containing the same data;

a state checking device of the memory apparatus configured to determine whether a respective memory bank is in an open memory bank state during which an open word line of the respective memory bank must be closed prior to reading further data from the respective memory bank; and

a control device of the memory apparatus configured, in response to a read command received by the memory apparatus, to:

select one of the first memory banks to be accessed for a reading operation when the state checking device determines that the respective one first memory bank is not in the open memory bank state, wherein the plurality of first memory banks are accessible using an address input interface in the memory apparatus, wherein the plurality of shadow memory banks are accessible using the control device and not the address input interface,

select the first shadow memory bank to be accessed when the state checking device determines that the selected first memory bank is in the open memory bank state and the first shadow memory bank is not in the open memory bank state, and

select the second shadow memory bank to be accessed when the state checking device determines that the selected first memory bank and the first shadow memory bank are in the open memory bank state,

wherein the control device is configured to write the same data to a respective first memory bank and the respectively associated first and second shadow memory banks at the same time.

8. The memory apparatus of claim 7 , wherein the state checking device is configured to determine the open memory bank state based on a comparison between a period of time that has elapsed since a previous read command was last applied to a respective memory bank and a minimum word line cycle time t RC of the respective memory bank.

9. The memory apparatus of claim 7 , wherein each respective memory bank is configured to generate a state signal which indicates whether the respective memory bank is in an open memory bank state and wherein the state checking device is configured to detect the state signal of each respective memory bank.

10. The memory apparatus of claim 7 , wherein the state checking device is a part of the control device.