M87C257 Datasheet, PDF (1/13 Pages) STMicroelectronics – ADDRESS LATCHED 256K 32K x 8 UV EPROM and OTP EPROM

M87C257
ADDRESS LATCHED
256K (32K x 8) UV EPROM and OTP EPROM
INTEGRATED ADDRESS LATCH
FAST ACCESS TIME: 45ns
LOW POWER “CMOS” CONSUMPTION:
– Active Current 30mA
– Standby Current 100µA
PROGRAMMING VOLTAGE: 12.75V
ELECTRONIC SIGNATURE for AUTOMATED
PROGRAMMING
PROGRAMMING TIMES of AROUND 3sec.
(PRESTO II ALGORITHM)
28
1
FDIP28W (F)
PLCC32 (C)
DESCRIPTION
The M87C257 is a high speed 262,144 bit UV
erasable and electrically programmable EPROM.
The M87C257 incorporates latches for all address
inputs to minimize chip count, reduce cost, and
simplify the design of multiplexed bus systems.
The Window Ceramic Frit-Seal Dual-in-Line pack-
age has a transparent lid which allows the user to
expose the chip to ultraviolet light to erase the bit
pattern. A new pattern can then be written to the
device by following the programming procedure.
For applications where the content is programmed
only one time and erasure is not required, the
M87C257 is offered in Plastic Leaded Chip Carrier,
package.
Table 1. Signal Names
A0 - A14
Address Inputs
Q0 - Q7
Data Outputs
E
Chip Enable
G
Output Enable
ASVPP
VCC
VSS
Address Strobe / Program Supply
Supply Voltage
Ground
Figure 1. Logic Diagram
VCC
15
A0-A14
E
G
ASVPP
M87C257
VSS
8
Q0-Q7
AI00928B
June 1996
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