bq4013/Y
128Kx8 Nonvolatile SRAM
The bq4013/Y uses an extremely
Features
General Description
low standby current CMOS SRAM,
coupled with a small lithium coin
cell to provide nonvolatility without
long write-cycle times and the
write-cycle limitations associated
with EEPROM.
➤ Data retention for at least 10
The CMOS bq4013/Y is a nonvolatile
1,048,576-bit static RAM organized as
131,072 words by 8 bits. The integral
control circuitry and lithium energy
source provide reliable nonvolatility
coupled with the unlimited write cy-
cles of standard SRAM.
years without power
➤ Automatic write-protection during
power-up/power-down cycles
➤ Conventional SRAM operation,
The bq4013/Y requires no external
circuitry and is socket-compatible
with industry-standard SRAMs and
most EPROMs and EEPROMs.
including unlimited write cycles
The control circuitry constantly
monitors the single 5V supply for an
out-of-tolerance condition. When
➤ Internal isolation of battery be-
fore power application
➤ Industry standard 32-pin DIP
V
CC falls out of tolerance, the SRAM
pinout
is unconditionally write-protected to
prevent inadvertent write operation.
At this time the integral energy
source is switched on to sustain the
memory until after VCC returns valid.
Pin Connections
Pin Names
A0–A16
Address inputs
WE
NC
Write enable input
No connect
DQ0–DQ7 Data input/output
CE
OE
Chip enable input
VCC
VSS
Supply voltage input
Ground
Output enable input
Selection Guide
Maximum
Negative
Supply
Tolerance
Maximum
Negative
Supply
Tolerance
Part
Number
Access
Part
Number
Access
Time (ns)
Time (ns)
bq4013YMA -70
bq4013YMA -85
bq4013YMA-120
70
85
-10%
-10%
-10%
bq4013MA -85
bq4013MA-120
85
-5%
-5%
120
120
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