X28HC256D-12 XICOR [Xicor Inc.], X28HC256D-12 Datasheet
X28HC256D-12
Related parts for X28HC256D-12
X28HC256D-12 Summary of contents
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... The X28HC256 supports a 128-byte page write opera- tion, effectively providing a 24 s/byte write cycle and enabling the entire memory to be typically rewritten in less than 0.8 seconds. The X28HC256 also features DATA Polling and Toggle Bit Polling, two methods of providing early end of write detection. The X28HC256 ...
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... X28HC256 PIN DESCRIPTIONS Addresses (A – The Address inputs select an 8-bit memory location during a read or write operation. Chip Enable (CE) The Chip Enable input must be LOW to enable all read/ write operations. When CE is HIGH, power consumption is reduced. Output Enable (OE) The Output Enable input controls the data output buffers and is used to initiate read operations ...
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... Page Write Operation The page write feature of the X28HC256 allows the entire memory to be written in typically 0.8 seconds. Page write allows up to one hundred twenty-eight bytes of data to be consecutively written to the X28HC256 prior to the commencement of the internal programming cycle ...
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X28HC256 DATA POLLING I/O 7 Figure 2. DATA Polling Bus Sequence LAST WRITE I – Figure 3. DATA Polling Software Flow WRITE DATA WRITES COMPLETE? YES SAVE LAST DATA ...
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X28HC256 THE TOGGLE BIT I/O 6 Figure 4. Toggle Bit Bus Sequence LAST WRITE I I/O 6 beginning and ending state of I/O 6 will vary. Figure 5. Toggle Bit Software Flow ...
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X28HC256 HARDWARE DATA PROTECTION The X28HC256 provides two hardware features that protect nonvolatile data from inadvertent writes. • Default V Sense—All write functions are inhibited CC when V is 3.5V Typically. CC • Write Inhibit—Holding either OE LOW, WE HIGH, ...
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X28HC256 SOFTWARE DATA PROTECTION Figure 6. Timing Sequence—Byte or Page Write DATA AA ADDRESS 5555 CE WE Figure 7. Write Sequence for Software Data Protection WRITE DATA AA TO ADDRESS 5555 WRITE DATA 55 TO ADDRESS 2AAA ...
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X28HC256 RESETTING SOFTWARE DATA PROTECTION Figure 8. Reset Software Data Protection Timing Sequence V CC DATA AA 55 ADDRESS 5555 2AAA CE WE Figure 9. Write Sequence for resetting Software Data Protection WRITE DATA AA TO ADDRESS 5555 WRITE DATA ...
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... Because the X28HC256 has two power modes, standby and active, proper decoupling of the memory array is of prime concern. Enabling CE will cause transient current spikes. The magnitude of these spikes is dependent on the output capacitive loading of the l/Os ...
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X28HC256 ABSOLUTE MAXIMUM RATINGS* Temperature under Bias X28HC256 .................................. – +85 C X28HC256I, X28HC256M ......... – +135 C Storage Temperature ....................... – +150 C Voltage on any Pin with Respect to V .................................. –1V ...
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X28HC256 POWER-UP TIMING Symbol PUR (3) t PUW (3) t CAPACITANCE 1MHz Symbol I/O (9) C Input/Output Capacitance IN (9) C Input Capacitance ENDURANCE AND DATA RETENTION Parameter Endurance Data Retention A.C. ...
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X28HC256 A.C. CHARACTERISTICS (Over the recommended operating conditions, unless otherwise specified.) Read Cycle Limits Symbol Parameter RC (5) t Read Cycle Time CE (5) t Chip Enable Access Time AA (5) t Address Access Time t Output Enable Access Time ...
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X28HC256 Write Cycle Limits Symbol WC (7) t Write Cycle Time t Address Setup Time AS t Address Hold Time AH t Write Setup Time CS t Write Hold Time CH CE Pulse Width HIGH Setup Time ...
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... Between successive byte writes within a page write operation, OE can be strobed LOW: e.g. this can be done with CE and Notes: (9) WE HIGH to fetch data from another memory device within the system for the next write; or with WE HIGH and CE LOW effectively performing a polling operation. (10) The timings shown above are unique to page write operations. Individual byte load operations within the page write must conform to either the controlled write cycle timing ...
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X28HC256 DATA Polling Timing Diagram (11 ADDRESS I/O 7 Toggle Bit Timing Diagram (11 OEH OE HIGH Z I/O 6 *I/O beginning and ending state will vary, depending upon ...
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X28HC256 PACKAGING INFORMATION 28-LEAD PLASTIC DUAL IN-LINE PACKAGE TYPE P PIN 1 INDEX PIN 1 SEATING PLANE 0.150 (3.81) 0.125 (3.17) 0.110 (2.79) 0.090 (2.29) TYP. 0.010 (0.25) NOTE: ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS) 1.460 (37.08) 1.400 ...
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X28HC256 PACKAGING INFORMATION 28-LEAD HERMETIC DUAL IN-LINE PACKAGE TYPE D PIN 1 SEATING PLANE 0.200 (5.08) 0.125 (3.18) 0.110 (2.79) 0.090 (2.29) TYP. 0.100 (2.54) TYP. 0.010 (0.25) NOTE: ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS) 1.490 (37.85) 1.435 ...
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X28HC256 PACKAGING INFORMATION 32-LEAD PLASTIC LEADED CHIP CARRIER PACKAGE TYPE J 0.420 (10.67) 0.045 (1.14 0.495 (12.57) 0.485 (12.32) TYP. 0.490 (12.45) 0.453 (11.51) 0.447 (11.35) TYP. 0.450 (11.43) 0.300 (7.62) REF. PIN 1 NOTES: 1. ALL DIMENSIONS ...
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X28HC256 PACKAGING INFORMATION 28-LEAD PLASTIC SMALL OUTLINE GULL WING PACKAGE TYPE S 0.1040 (2.6416) 0.0940 (2.3876) 0 – 8 NOTES: 1. ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS) 2. FORMED LEAD SHALL BE PLANAR WITH RESPECT TO ONE ANOTHER ...
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X28HC256 PACKAGING INFORMATION 32-PAD CERAMIC LEADLESS CHIP CARRIER PACKAGE TYPE E 0.150 (3.81) BSC 0.015 (0.38) 0.003 (0.08) PIN 1 0.200 (5.08) BSC 0.028 (0.71) 0.022 (0.56) (32) PLCS. 0.458 (11.63) 0.442 (11.22) 0.458 (11.63) 0.300 (7.62) 32 NOTE: 1. ...
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X28HC256 PACKAGING INFORMATION 28-LEAD CERAMIC PIN GRID ARRAY PACKAGE TYPE TYP. 0.100 ALL LEADS PIN 1 INDEX 0.660 (16.76) 0.640 (16.26) NOTE: ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS ...
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X28HC256 PACKAGING INFORMATION 0.740 (18.80) MAX. 0.006 (0.15) 0.003 (0.08) 0.370 (9.40) 0.250 (6.35) TYP. 0.300 2 PLCS. NOTE: ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS) 28-LEAD CERAMIC FLAT PACK PIN 1 INDEX 1 28 0.440 (11.18) MAX. 0.180 ...
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X28HC256 PACKAGING INFORMATION SEE NOTE 2 8.02 (0.315) 7.98 (0.314) 1.18 (0.046) 1.02 (0.040) 0.58 (0.023) 0.42 (0.017) SOLDER PADS FOOTPRINT NOTE: 1. ALL DIMENSIONS ARE SHOWN IN MILLIMETERS (INCHES IN PARENTHESES). 32-LEAD THIN SMALL OUTLINE PACKAGE (TSOP) TYPE T ...
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X28HC256 ORDERING INFORMATION X28HC256 Device LIMITED WARRANTY Devices sold by Xicor, Inc. are covered by the warranty and patent indemnification provisions appearing in its Terms of Sale only. Xicor, Inc. makes no warranty, express, statutory, implied description regarding ...