27C256T
256K (32K x 8-Bit) OTP EPROM
A5-A9
1024 x 1022
Memory Matrix
x-Decoder
A12-A14
A12-A16
NC
I/O0
Y- Gating
Input
Data
Control
I/O 7
I/O15
Y - Decoder
27C256T
CE
OE
A0-A4
A10-A11
PGM
VCC
VPP
VSS
H
H
: High Threshhold Inverter
Logic Diagram
FEATURES:
DESCRIPTION:
• 32K x 8-bit OTP EPROM organization
• RAD-PAK® radiation-hardened against natural space
radiation
• Total dose hardness:
- > 100 Krad (Si), depending upon space mission
• Excellent Single Event Effects:
Maxwell Technologies’ 27C256T high density 256-Kilobit one-
time programmable electrically programmable read only mem-
ory microcircuit features a greater than 100 krad (Si) total
dose tolerance, depending upon space mission. The 27C256T
features fast address times and low power dissipation. The
27C256T offers high speed programming using page pro-
gramming mode.
-SEL > 80 MeV/mg/cm2
TH
-SEUTH > 80 Mev/mg/cm2
• Package:
-32 pin RAD-PAK® flat pack
-32 pin RAD-PAK® DIP
• Fast access time:
- 120, 150, 200 ns (max)
• Low power dissipation:
- Active mode: 100 mW/MHz (typ)
- Standby mode: 10 µW (typ)
Page programming time: 14 sec (typ)
• Programming power supply:
Maxwell Technologies' patented RAD-PAK® packaging technol-
ogy incorporates radiation shielding in the microcircuit pack-
age. It eliminates the need for box shielding while providing
the required radiation shielding for a lifetime in orbit or space
mission. In a GEO orbit, RAD-PAK® provides greater than 100
krad (Si) radiation dose tolerance. This product is available
with screening up to Class S.
- V = 12.5 V
PP
• One-time programmable
• Pin arrangement
- JEDEC standard byte-wide EPROM
- Flash memory and mask ROM compatible
06.24.02 REV 4
1
All data sheets are subject to change without notice
(858) 503-3300 - Fax: (858) 503-3301 - www.maxwell.com
©2003 Maxwell Technologies
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