HD6432345 Datasheet, PDF (562/907 Pages) Hitachi Semiconductor – H8S/2345 F-ZTAT Hardware Manual

• The size of the H8S/2345 Series PROM is 128 kbytes. Always set addresses within the range
H'00000 to H'1FFFF. During programming, write H'FF to unused addresses to avoid
verification errors.
17.5.4 Reliability of Programmed Data
An effective way to assure the data retention characteristics of the programmed chips is to bake
them at 150°C, then screen them for data errors. This procedure quickly eliminates chips with
PROM memory cells prone to early failure.
Figure 17.6 shows the recommended screening procedure.
Program chip and verify data
Bake chip for 24 to 48 hours at
125°C to 150°C with power off
Read and check program
Mount
Figure 17.6 Recommended Screening Procedure
If a series of programming errors occurs while the same PROM programmer is being used, stop
programming and check the PROM programmer and socket adapter for defects.
Please inform Hitachi of any abnormal conditions noted during or after programming or in
screening of program data after high-temperature baking.
550