X22C12
X22C12
1K Bit
256 x 4
Nonvolatile Static RAM FEATURES
DESCRIPTION
•
The X22C12 is a 256 x 4 CMOS NOVRAM featuring a high-speed static RAM overlaid bit-for-bit with a nonvolatile E2PROM. The NOVRAM design allows data to be easily transferred from RAM to E 2PROM (STORE) and from E 2PROM to RAM (RECALL). The STORE operation is completed within 5ms or less and the RECALL is completed within 1 µs.
High Performance CMOS —150ns RAM Access Time • High Reliability —Store Cycles: 1,000,000 —Data Retention: 100 Years • Low Power Consumption —Active: 40mA Max. —Standby: 100µA Max. • Infinite Array Recall, RAM Read and Write Cycles • Nonvolatile Store Inhibit: VCC = 3.5V Typical • Fully TTL and CMOS Compatible • JEDEC Standard 18-Pin 300-mil DIP • 100% Compatible with X2212 —With Timing Enhancements
Xicor NOVRAMs are designed for unlimited write operations to the RAM, either RECALLs from E 2PROM or writes from the host. The X22C12 will reliably endure 1,000,000 STORE cycles. Inherent data retention is greater than 100 years.
FUNCTIONAL DIAGRAM
PIN CONFIGURATION PLASTIC DIP CERDIP
2 NONVOLATILE E PROM MEMORY ARRAY A0
STORE
A7
1
18
VCC
A
2
17
A
X22C12 PIN DESCRIPTIONS AND DEVICE OPERATION
RECALL
Addresses (A0 –A7)
The RECALL input, input, when LOW, will initiate the transfer of the entire contents of the E 2PROM array to the RAM array. The transfer of data will be completed in 1 µs or less.
The address inputs select a 4-bit memory location during a read or write operation. Chip Select (CS ) The Chip Select input must be LOW to enable read or write operations with the RAM array. CS HIGH HIGH will place the I/O pins in the high impedance state.
An array recall has priority over RAM RA M read/write operations and will terminate both operations when RECALL is asserted. RECALL LOW LOW will also inhibit the STORE input.
Write Enable (WE )
Automatic Recall
The Write Enable input controls the I/O buffers, determining whether a RAM read or write operation is enabled. When CS is is LOW and WE is is HIGH, the I/O pins will output data from the selected RAM address locations. When both CS and and WE are are LOW, data presented at the I/O pins will be written to the selected address location.
Upon power-up the X22C12 will automatically recall data from the E 2PROM array into the RAM array.
Data In/Data Out (I/O1 –I/O4)
• VCC Sense—All functions are inhibited when V CC is <3.5V typical.
Data is written to or read from the X22C12 through the I/O pins. The I/O pins are placed in the high impedance state when either CS is is HIGH or during either a store or recall operation. STORE
The STORE input, input, when LOW, will initiate ini tiate the transfer of
Write Protection The X22C12 has three write protect features that are employed to protect the contents of the nonvolatile memory.
• Writ Write e Inh Inhibit— ibit—Holdin Holding g either either STORE HIGH or LOW during power-up or power-down will RECALL LOW prevent an inadvertent store operation and E 2PROM data integrity will be maintained. • Noise Noise Pro Protec tectio tion—A n—A STORE pulse pulse of typically less than 20ns will not initiate a store cycle.
X22C12 ABSOLUTE MAXIMUM RATINGS Temperature Temper ature under Bias .... ........ ........ ........ ...... .. –65 °C to +135°C Storage Temperature ........... ...................... ............. –65 °C to +150°C Voltage on any Pin with Respect to VSS ....................................... –1V to +7V D.C. Output Current ........... ....................... ....................... ..................... .......... 5mA Lead Temperature (Soldering, 10 seconds) ........... ....................... ................... ....... 300 °C
COMMENT Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only and the functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
RECOMMENDED OPERATING CONDITIONS Temperature
Min.
M ax .
Supply Voltage
Limits
Commercial Industrial Military
0°C –40°C –55°C
+70°C +85°C +125°C
X22C12
5V ± 10% 3817 PGM T13
3817 PGM T12.1
D.C. OPERATING CHARACTERI CHARACTERISTICS STICS(Over (Over the recommend recommended ed operating conditions, unless otherwise specified.) Limits Symbol lCC
ISB1 ISB2
Parameter
Min.
M ax.
Units
Test Conditions
mA
CS = = VIL, I/Os = Open, All Others =
2
mA
10 0
µA
VIH, Addresses = 0.4V/2.4V Levels @ f = 8MHz Store or Recall Functions Not Active, I/Os = Open, All Other Inputs = V IH Stor St ore e or or Rec Recal alll fun funct ctio ions ns No Nott Ac Acti tive ve,,
VCC S Su upply Current, RAM Read/Write
40
VCC S Sttandby Current (TTL Inputs) VCC Standby Current
X22C12 MODE SELECTION CE
WE
RECALL
H L L L X H X H
X H L L H X H X
H H H H L L H H
STORE
H H H H H H L L
I/ O
Mode Not Selected(3) Read RAM Write “1” RAM Write “0” RAM Array Recall Array Recall Nonvolatile Store(4) Nonvolatile Store(4)
Output High Z Output Data Input Data High Input Data Low Output High Z Output High Z Output High Z Output High Z
3817 PGM T05.1
ENDURANCE AND DATA RETENTION Parameter Endurance Store Cycles Data Retention
Min.
Units
100,000 1,000,000 1 00
Data Changes Per Bit Store Cycles Years 3817 PGM T06
POWER-UP TIMING Symbol
Parameter
M ax .
Units
tPUR(5) tPUW(5)
Power-up to Read Operation Power-up to Write or Store Operation
100 5
µs
ms 3817 PGM T07
X22C12 A.C. CHARACTERISTICS (Over the recommended operating conditions, unless otherwise specified.) Read Cycle Limits Symbol
Parameter
Min.
tRC tAA tCO tOH tLZ(6) tHZ(6)
Read Cycle Time Access Time Chip Select to Output Valid Output Hold from Address Change Chip Select to Output in Low Z Chip Deselect to Output in High Z
150
M ax .
Units ns ns ns ns ns ns
1 50 1 50 0 0 50
3817 PGM T08
Read Cycle tRC ADDRESS tA
tOH
tCO
tHZ
CS tLZ DATA I/O
DATA VALID 3817 FHD F03
X22C12 Write Cycle Limits Symbol
Parameter
Min.
tWC tCW tAS tWP tWR tDW tDH tWZ tOW
Write Cycle Time Chip Select to End of Write Address Setup Time Write Pulse Width Write Recovery Time Data Valid to End of Write Data Hold Time Write Enable to Output in High Z Output Active from End of Write
1 50 90 0 90 0 40 0
M a x.
50 0
Units ns ns ns ns ns ns ns ns ns 3817 PGM T09.1
Write Cycle tWC ADDRESS tCW CS tAS
tWP
tWR
WE tDW
tDH
X22C12 Recall Cycle Limits Symbol tRCC tRCP(7) tRCZ tORC tARC
Parameter Array Recall Time Recall Pulse Width Recall to Output in High Z Output Active from End of Recall Recalled Data Access Time from End of Recall
Min.
M ax .
Units
1
µs
90 50 0 12 0
ns ns ns ns 3817 PGM T10
Recall Cycle
ADDRESS tRCP
tRCC
RECALL
CS tRCZ
tORC
DATA I/O tARC 3817 FHD F06
X22C12 Store Cycle Limits Symbol tSTC tSTP tSTZ tOST
Parameter
Min.
Internal Store Time Store Pulse Width Store to Output in High Z Output Active from End of Store
M a x.
Units
5
ms ns ns ns
90 50 0
3817 PGM T11
Store Cycle Limits tSTC tSTP STORE tSTZ DATA I/O
tOST HI Z
3817 FHD F07
SYMBOL TABLE WAVEFORM
INPUTS
OUTPUTS
X22C12 18-LEAD PLASTIC DUAL IN-LINE PACKAGE TYPE P
0.915 (23.24) 0.894 (22.71)
0.270 (6.86) 0.250 (6.35) PIN 1 INDEX PIN 1 0.800 (20.32) REF.
SEATING PLANE 0.140 (3.56)
0.060 (1.52) 0.050 (1.27)
0.165 (4.19) 0.130 (3.30)
0.025 (0.51) 0.005 (0.13)
X22C12 18-LEAD HERMETIC DUAL IN-LINE PACKAGE PACKAGE TYPE D
0.960 (24.38) ––
0.310 (7.87) 0.220 (5.59)
PIN 1
0.005 (0.13) MIN. 0.800 (20.32) REF.
SEATING PLANE
0.150 (3.81) MIN.
0.098 (2.49) ––
0.200 (5.08) –– 0.070 (1.78) 0.015 (0.38)
0.200 (5.08) 0.125 (3.18)
0.110 (2.79)
0.065 (1.65)
0.023 (0.58)
X22C12 20-LEAD PLASTIC SMALL OUTLINE GULL WING PACKAGE PACKAGE TYPE S
0.290 (7.37) 0.299 (7.60)
0.393 (10.00) 0.420 (10.65)
PIN 1 INDEX
PIN 1
0.014 (0.35) 0.020 (0.50) 0.496 (12.60) 0.508 (12.90)
(4X) 7°
0.092 (2.35) 0.105 (2.65)
0.003 (0.10)
X22C12 ORDERING INFORMATION
X 2 2 C1 2 Device
X
X Store Cycles Blank = 1,000,000 Temperature Range Blank = Commercial = 0 °C to +70°C I = Industrial = –40 °C to +85°C M = Military = –55 °C to +125°C MB = MIL-STD-883 Package P = 18-Lead Plastic DIP D = 18-Lead Cerdip S = 20-Lead Plastic SOIC (300 mil)
