HD64F7045F28V Datasheet, PDF (720/925 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH RISC engine Family/SH7040 Series

5. Terminate the writing if a write malfunction occurs in consecutive addresses. In such cases,
check for problems in the EPROM writer and/or socket adapter. There are some cases where
write/verify will not be possible if using an EPROM writer with a high impedance power
supply system.
6. Use a EPROM writer that conforms to the socket adapter supported by this LSI.
21.3.4 Post-Write Reliability
High temperature biasing (or burn-in) of devices is recommended after writing in order to improve
the data retention characteristics. High temperature biasing is a method of screening that
eliminates parts with faulty initial data retention by on-chip PROM memory cells within a short
period of time. Figure 21.8 shows the flow from the on-chip PROM programming including
screening to the installation of the device on a board.
Program write/verify
Figure 21.5 (flowchart)
Unpowered high-
temperature bias
(125–150°C, 24–48 hours)
Data read out and verify
(V_CC = 5.0 V)
Installation on board
Figure 21.8 Screening Flow
If there are any abnormalities in program write/verify or program read-out verification after high
temperature biasing, please contact a Renesas Technology technical representative.
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