tAVAV
A(14:0)
CE
tAVQV
tELQX
tELQV
tEHQZ
OE
tGHQZ
tAXQX
tGLQV
tGLQX
tAVQV
DQ(7:0)
Figure 2. PROM Read Cycle
RADIATION HARDNESS
maintaining the circuit density and reliability. For transient
radiation hardness and latchup immunity, UTMC builds all
radiation-hardened products on epitaxial wafers using an
advanced twin-tub CMOS process. In addition, UTMC pays
special attention to power and ground distribution during the
design phase, minimizing dose-rate upset caused by rail collapse.
The UT28F256 PROM incorporates special design and layout
features which allow operation in high-level radiation
environments. UTMC has developed special low-temperature
processing techniques designed to enhance the total-dose
radiation hardness of both the gate oxide and the field oxide while
RADIATION HARDNESS DESIGN SPECIFICATIONS 1
Total Dose
1E6
rad(Si)
MeV-cm2/mg
MeV-cm2/mg
MeV-cm2/mg
cm 2
Latchup LET Threshold
>128
Memory Cell LET Threshold
Transient Upset LET Threshold
>128
54
Transient Upset Device Cross Section @ LET=128 MeV-cm2/mg
1E-6
Note:
1. The PROM will not latchup during radiation exposure under recommended operating conditions.
5
AEROFLEX [ AEROFLEX CIRCUIT TECHNOLOGY ]
