HD64F3437TF16 Datasheet, PDF (403/752 Pages) Hitachi Semiconductor – 12 V must not be applied to the S-mask model (single-power-supply specification), as this may permanently damage the device.

18.3.3 Reliability of Programmed Data
An effective way to assure the data holding 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 18.7 shows the recommended screening procedure.
Write and verify program
Bake with power off
125° to 150°C, 24 to 48Hr
Read and check program
Mount
Figure 18.7 Recommended Screening Procedure
If a series of write errors occurs while the same PROM programmer is in use, stop programming
and check the PROM programmer and socket adapter for defects.
Please inform Hitachi of any abnormal conditions noted during programming or in screening of
program data after high-temperature baking.
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