K7N323645M

- 8 -

Rev 2.0

Nov. 2003

K7N321845M

FUNCTION DESCRIPTION

there is transition from Read to Write, or vice versa.

All inputs (with the exception of OE, LBO and ZZ) are synchronized to rising clock edges.

All read, write and deselect cycles are initiated by the ADV input. Subsequent burst addresses can be internally generated by the

burst advance pin (ADV). ADV should be driven to Low once the device has been deselected in order to load a new address for next

operation.

Clock Enable(CKE) pin allows the operation of the chip to be suspended as long as necessary. When CKE is high, all synchronous

inputs are ignored and the internal device registers will hold their previous values.

are active .

Output Enable(OE ) can be used to disable the output at any given time.

Read operation is initiated when at the rising edge of the clock, the address presented to the address inputs are latched in the

high, and ADV driven low.The internal array is read between the first rising edge and the second rising edge of the clock and the data

is latched in the output register. At the second clock edge the data is driven out of the SRAM. Also during read operation OE must

be driven low for the device to drive out the requested data.

Write operation occurs when WE is driven low at the rising edge of the clock. BW[d:a] can be used for byte write operation. The pipe-

At the first rising edge of the clock, WE and address are registered, and the data associated with that address is required two cycle

later.

Subsequent addresses are generated by ADV High for the burst access as shown below. The starting point of the burst seguence is

provided by the external address. The burst address counter wraps around to its initial state upon completion.

The burst sequence is determined by the state of the LBO pin. When this pin is low, linear burst sequence is selected.

And when this pin is high, Interleaved burst sequence is selected.

During normal operation, ZZ must be driven low. When ZZ is driven high, the SRAM will enter a Power Sleep Mode after 2 cycles. At

this time, internal state of the SRAM is preserved. When ZZ returns to low, the SRAM normally operates after 2 cycles of wake up

time.

BURST SEQUENCE TABLE

(Interleaved Burst, LBO=High)

LBO PIN

HIGH

Case 1

Case 2

Case 3

Case 4

First Address

Fourth Address

0

0

1

1

0

1

0

1

0

0

1

1

1

0

1

0

1

1

0

0

0

1

0

1

1

1

0

0

1

0

1

0

BQ TABLE

(Linear Burst, LBO=Low)

Note : 1. LBO pin must be tied to High or Low, and Floating State must not be allowed

.

LBO PIN

LOW

Case 1

Case 2

Case 3

Case 4

First Address

Fourth Address

0

0

1

1

0

1

0

1

0

1

1

0

1

0

1

0

1

1

0

0

0

1

0

1

1

0

0

1

1

0

1

0