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¡ Semiconductor

MSM518205

Notes:

1. A start-up delay of 200

µs is required after power-up, followed by a minimum of eight

initialization cycles (RAS-only refresh or CAS before RAS refresh) before proper device

operation is achieved.

4. This parameter is measured with a load circuit equivalent to 2 TTL loads and 100 pF.

output achieves the open circuit condition and are not referenced to output voltage

levels.

the cycle is an early write cycle and the data out will remain open circuit (high

cycle and data out will contain data read from the selected cell; if neither of the above

sets of conditions is satisfied, then the condition of the data out (at access time) is

indeterminate.

11. These parameters are referenced to the CAS leading edge in an early write cycle, and

to the WE leading edge in an OE control write cycle, or a read modify write cycle.

12. The test mode is initiated by performing a WE and CAS before RAS refresh cycle.

This mode is latched and remains in effect until the exit cycle is generated. In a test mode

CA0 and CA1 are not used and each DQ pin now accesses 4-bit locations. Since all 2 DQ

pins are used, a total of 8 data bits can be written in parallel into the memory array. In

a read cycle, if 4 data bits are equal, the DQ pin will indicate a high level. If the 4 data

bits are not equal, the DQ pin will indicate a low level. The test mode is cleared and the

memory device returned to its normal operating state by performing a RAS-only

refresh cycle or a CAS before RAS refresh cycle.

13. In a test mode read cycle, the value of access time parameters is delayed for 5 ns for the

specified value. These parameters should be specified in test mode cycle by adding the

above value to the specified value in this data sheet.

14. These parameters are determined by the falling edge of either CAS1 or CAS2,

whichever is earlier.

15. These parameters are determined by the rising edge of either CAS1 or CAS2,

whichever is later.