Cypress CY7C185 Switching Waveforms, Read Cycle No.19,10, Write Cycle No WE Controlled10,12

CY7C185

Switching Waveforms

Read Cycle No.1[9,10]

tRC

ADDRESS

tAA

tOHA

DATA OUT PREVIOUS DATA VALID

DATA VALID

C185–6

Read Cycle No.2[11,12]
CE1		tRC
CE2	t
	ACE
OE
	tDOE	tHZOE
		tHZCE
	tLZOE		HIGH
DATA OUT	HIGH IMPEDANCE	DATA VALID	IMPEDANCE
	tLZCE	tPD
	tPU
VCC			ICC
SUPPLY	50%		50%
CURRENT			ISB
			C185–7

Write Cycle No. 1 (WE Controlled)[10,12]

tWC

ADDRESS

CE1 tSCEI

tAW tHA

CE2		tSCE2
	tSA		tPWE

WE

OE
		tSD	tHD
		DATA IN VALID
DATA I/O	NOTE 13
	tHZOE		C185–8

9.Device is continuously selected. OE, CE1 = VIL. CE2 = VIH.

10.WE is HIGH for read cycle.

11.Data I/O is High Z if OE = VIH, CE1 = VIH, WE = VIL, or CE2=VIL.

12.The internal write time of the memory is defined by the overlap of CE1 LOW, CE2 HIGH and WE LOW. CE1 and WE must be LOW and CE2 must be HIGH to initiate write. A write can be terminated by CE1 or WE going HIGH or CE2 going LOW. The data input set-up and hold timing should be referenced to the rising edge of the signal that terminates the write.

13.During this period, the I/Os are in the output state and input signals should not be applied.

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