XICOR X20C04P, X20C04JM-25, X20C04JM-20, X20C04JM-15, X20C04JM Datasheet

X20C04

4K X20C04 512 x 8 Bit

Nonvolatile Static RAM

FEATURES

• High Reliability

—Endurance: 1,000,000 Nonvolatile Store

Operations

—Retention: 100 Years Minimum

• Power-on Recall

—E2PROM Data Automatically Recalled Into

SRAM Upon Power-up

• Lock Out Inadvertent Store Operations

• Low Power CMOS

—Standby: 250µA

• Infinite E

and Write Cycles

2

PROM Array Recall, and RAM Read

• Compatible with X2004

PIN CONFIGURATION

DESCRIPTION

The Xicor X20C04 is a 512 x 8 NOVRAM featuring a
static RAM overlaid bit-for-bit with a nonvolatile electri­cally erasable PROM (E2PROM). The X20C04 is fabri­cated with advanced CMOS floating gate technology to
achieve low power and wide power-supply margin. The
X20C04 features the JEDEC approved pinout for byte­wide memories, compatible with industry standard RAMs,
ROMs, EPROMs, and E2PROMs.

The NOVRAM design allows data to be easily trans­ferred from RAM to E2PROM (store) and E2PROM to
RAM (recall). The store operation is completed in 5ms or
less and the recall operation is completed in 5µs or less.

Xicor NOVRAMS are designed for unlimited write
operations to RAM, either from the host or recalls from
E2PROM, and a minimum 1,000,000 store operations to
the E2PROM. Data retention is specified to be greater
than 100 years.

I/O
I/O
I/O

V

NE
NC

A
A
A
A
A
A
A
A

SS

7

A

NCNENC

(TOP VIEW)

2

I/O1I/O

LCC

PLCC

X20C04

SS

NC

V

VCCWE

NC

29
28
27
26
25
24
23
22
21

I/O3I/O4I/O

3825 FHD F03

A

8

NC
NC
NC
OE
NC
CE
I/O

7

I/O

6

5

PLASTIC

CERDIP

1
2
3

7

4

6

5

5

6

4

7

3
2
1
0
0
1
2

8
9
10
11
12
13
14

X20C04

28
27
26
25
24
23
22
21
20
19
18
17
16
15

3825 FHD F02

V
WE
NC
A
NC
NC
OE
NC
CE
I/O
I/O
I/O
I/O
I/O

CC

8

4321323130

A

5

6

6

A

5

7

A

4

8

A

3

9

A

2

10

A

1

11

A

I/O

NC

0

12
13

0

14 15 16 17 18 19 20

7
6
5
4
3

©Xicor, Inc. 1992, 1995, 1996 Patents Pending Characteristics subject to change without notice
3825-2.8 7/31/97 T4/C0/D0 SH

1

X20C04

PIN DESCRIPTIONS

Addresses (A0–A8)

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 and recall operations. Output
Enable LOW disables a store operation regardless of
the state of CE, WE, or NE.

Data In/Data Out (I/O0–I/O7)

Data is written to or read from the X20C04 through the
I/O pins. The I/O pins are placed in the high impedance
state when either CE or OE is HIGH or when NE is LOW.

FUNCTIONAL DIAGRAM

Write Enable (WE)

The Write Enable input controls the writing of data to
both the static RAM and stores to the E2PROM.

Nonvolatile Enable (NE)

The Nonvolatile Enable input controls all accesses to
the E2PROM array (store and recall functions).

PIN NAMES

Symbol Description

A0–A

8

I/O0–I/O

7

Address Inputs
Data Input/Output

WE Write Enable
CE Chip Enable
OE Output Enable
NE Nonvolatile Enable

V

CC

V

SS

+5V
Ground

NC No Connect

3825 PGM T01

A3–A

A0–A

A7–A

CE

OE

WE

NE

VCC SENSE

EEPROM ARRA Y

6

CONTROL

LOGIC

2

8

ROW

SELECT

512 x 8

SRAM

ARRAY

COLUMN

SELECT

&

I/OS

I/O0–I/O

7

RECALL

STORE

3825 FHD F01

2

X20C04

DEVICE OPERATION

The CE, OE, WE and NE inputs control the X20C04
operation. The X20C04 byte-wide NOVRAM uses a
2-line control architecture to eliminate bus contention in
a system environment. The I/O bus will be in a high
impedance state when either OE or CE is HIGH, or
when NE is LOW.

RAM Operations

RAM read and write operations are performed as they
would be with any static RAM. A read operation requires
CE and OE to be LOW with WE and NE HIGH. A write
operation requires CE and WE to be LOW with NE
HIGH. There is no limit to the number of read or write
operations performed to the RAM portion of the X20C04.

Nonvolatile Operations

With NE LOW, recall operation is performed in the same
manner as RAM read operation. A recall operation
causes the entire contents of the E2PROM to be written
into the RAM array. The time required for the operation
to complete is 5µs or less. A store operation causes the
entire contents of the RAM array to be stored in the
nonvolatile E2PROM. The time for the operation to
complete is 5ms or less.

Power-Up Recall

Upon power-up (VCC), the X20C04 performs an auto­matic array recall. When VCC minimum is reached, the
recall is initiated, regardless of the state of CE, OE, WE
and NE.

Write Protection

The X20C04 has five write protect features that are
employed to protect the contents of both the nonvolatile
memory and the RAM.

•VCC Sense—All functions are inhibited when VCC is
≤ 3.5V.

• A RAM write is required before a Store Cycle is
initiated.

• Write Inhibit—Holding either OE LOW, WE HIGH,
CE HIGH, or NE HIGH during power-up and power-
down will prevent an inadvertent store operation.

• Noise Protection—A combined WE, NE, OE and
CE pulse of less than 20ns will not initiate a Store
Cycle.

• Noise Protection—A combined WE, NE, OE and
CE pulse of less than 20ns will not initiate a recall
cycle.

SYMBOL TABLE

WAVEFORM

INPUTS

Must be
steady

May change
from LOW
to HIGH

May change
from HIGH
to LOW

Don’t Care:
Changes
Allowed

N/A

OUTPUTS

Will be
steady

Will change
from LOW
to HIGH

Will change
from HIGH
to LOW

Changing:
State Not
Known

Center Line
is High
Impedance

3

X20C04

ABSOLUTE MAXIMUM RATINGS*

Temperature under Bias .................. –65°C to +135°C

Storage Temperature ....................... –65°C to +150°C

Voltage on any Pin with

Respect to V

.......................................

SS

–1V to +7V

D.C. Output Current ...........................................10mA

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. Max.

Commercial 0°C +70°C
Industrial –40°C +85°C
Military –55°C +125°C

3825 PGM T02.1

Supply Voltage Limits

X20C04 5V ±10%

3825 PGM T03

D.C. OPERATING CHARACTERISTICS (Over recommended operating conditions unless otherwise specified.)

Limits

Symbol Parameter Min. Max. Units Test Conditions

l

CC1

VCC Current (Active) 100 mA NE = WE = VIH, CE = OE = V

IL

Address Inputs = 0.4V/2.4V levels
@ f = 5MHz. All I/Os = Open

I

CC2

VCC Current During Store 10 mA All Inputs = V

IH

All I/Os = Open

I

SB1

VCC Standby Current 10 mA CE = V

IH

(TTL Input) All Other Inputs = VIH, All I/Os = Open

I

SB2

VCC Standby Current 250 µA All Inputs = V

CC

– 0.3V

(CMOS Input) All I/Os = Open
I
I
V
V
V
V

LI
LO

IL
IH
OL
OH

(1)

(1)

Input Leakage Current 10 µAVIN = VSS to V

Output Leakage Current 10 µAV

= VSS to VCC, CE = V

OUT

Input LOW Voltage –1 0.8 V

Input HIGH Voltage 2 V

+ 0.5 V

CC

Output LOW Voltage 0.4 V IOL = 2.1mA

Output HIGH Voltage 2.4 V IOH = –400µA

CC

IH

3825 PGM T04.3

POWER-UP TIMING

Symbol Parameter Max. Units

(2)

t

PUR

t

PUW

(2)

Power-Up to RAM Operation 100 µs
Power-Up to Nonvolatile Operation 5 ms

CAPACITANCE TA = +25°C, F = 1MHz, VCC = 5V.

Symbol Test Max. Units Conditions

(2)

C

I/O

(2)

C

IN

Notes: (1) VIL min. and VIH max. are for reference only and are not tested.

(2) This parameter is periodically sampled and not 100% tested.

Input/Output Capacitance 10 pF V
Input Capacitance 6 pF VIN = 0V

4

3825 PGM T05

= 0V

I/O

3825 PGM T06.1

X20C04

ENDURANCE AND DATA RETENTION

Parameter Min. Units

Endurance 100,000 Data Changes Per Bit
Store Cycles 1,000,000 Store Cycles
Data Retention 100 Years

MODE SELECTION

CE WE NE OE Mode I/O Power

H X X X Not Selected Output High Z Standby

L H H L Read RAM Output Data Active
L L H H Write “1” RAM Input Data High Active
L L H H Write “0” RAM Input Data Low Active
L H L L Array Recall Output High Z Active
L L L H Nonvolatile Storing Output High Z Active
L H H H Output Disabled Output High Z Active
L L L L Not Allowed Output High Z Active
L H L H No Operation Output High Z Active

3825 PGM T07.1

3825 PGM T09.1

EQUIVALENT A.C. LOAD CIRCUIT A.C. CONDITIONS OF TEST

Input Pulse Levels 0V to 3V

5V

Input Rise and
Fall Times 10ns

1.92KΩ

Input and Output
Timing Levels 1.5V

OUTPUT

1.37KΩ

100pF

3825 FHD F04.1

3825 PGM T08.2

5