
RADIATION
 Fabricated with RICMOS IV Silicon on Insulator (SOI)
0.7
 μ
m Process  (L
eff
= 0.55 
μ
m)
 Total Dose Hardness through 1x10
6
 rad(SiO
2
)
 Neutron Hardness through 1x10
14
 cm
-2
 Dynamic and Static Transient Upset Hardness
through 1x10
11
 rad (Si)/s
 Dose Rate Survivability through <1x10
12
 rad(Si)/s
 Soft Error Rate of <1x10
-10
 upsets/bit-day in
Geosynchronous Orbit
 No Latchup
128K x 8 STATIC RAM—SOI
HX6228
OTHER
 Read/Write Cycle Times
≤
 16 ns (Typical)
≤
 25 ns (-55 to 125
°
C)
 Typical Operating Power <25 mW/MHz
 Asynchronous Operation
 CMOS or TTL Compatible I/O
 Single 5 V 
±
 10% Power Supply
 Packaging Options
- 32-Lead Flat Pack (0.820 in. x 0.600 in.)
- 40-Lead Flat Pack (0.775 in. x 0.710 in.)
Military & Space Products
GENERAL DESCRIPTION
The 128K x 8 Radiation Hardened Static RAM is a high
performance 131,072 word x 8-bit static random access
memory with industry-standard functionality. It is fabricated
with Honeywell’s radiation hardened technology, and is
designed for use in systems operating in radiation environ-
ments. The RAM operates over the full military temperature
range and requires only a single 5 V 
±
 10% power supply. The
RAM is wire bond programmable for either TTL or CMOS
compatible I/O. Power consumption is typically less than 25
mW/MHz in operation, and less than 5 mW in the low power
disabled mode. The RAM read operation is fully asynchro-
nous, with an associated typical access time of 15 ns at 5V.
Honeywell’s enhancedSOI RICMOSIV (Radiation Insen-
sitive CMOS) technology is radiation hardened through the
use of advanced and proprietary design, layout and process
hardening techniques. The RICMOS IV process is an
advanced 5-volt, SIMOX CMOS technology with a 150 
gate oxide and a minimum feature size of 0.7 
μ
m (0.55 
μ
m
effective gate length—L
). Additional features include
Honeywell’s proprietary SHARP planarization process, and
a lightly doped drain (LDD) structure for improved short
channel reliability. A 7 transistor (7T) memory cell is used for
superior single event upset hardening, while three layer
metal power bussing and the low collection volume SIMOX
substrate provide improved dose rate hardening.
FEATURES