7477 datasheet(204/354 Pages) RENESAS

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7470/7471/7477/7478 GROUP USER’S MANUAL

HARDWARE

1.19 Built-in PROM version

(2) One Time PROM version

s Precautions before use

q The PROM of the One Time PROM version is

not tested or screened in the assembly process

and following processes. To ensure proper

operation after programming, the procedure

shown in Figure 1.19.7 is recommended to

verify programming.

Fig. 1.19.7 Programming and testing of One

Time PROM version

(3) Built-in EPROM version

s Precautions on erasing

q Sunlight and fluorescent light include light that may erase the information written in the built-in

PROM. When using the built-in EPROM version in the read mode, be sure to cover the transparent

glass portion with a seal.

q This seal to cover the transparent glass portion is prepared on our side. Be careful not to bring

the seal into contact with the microcomputer lead wires when covering the portion with the seal

because this seal is made of metal (aluminum).

q Before erasing data, clean the transparent glass. If any finger stain or seal adhesive is stuck to

the transparent glass, this prevents ultraviolet rays from passing, thereby affecting the erase

characteristic adversely.

Programming with PROM programmer

Screening (Caution)

(Leave at 150°C for 40 hours)

Verification with PROM programmer

Functional check in target device

Caution: The screening temperature is far higher

than the storage temperature. Never expose to

150°C exceeding 100 Hours.

7477 Datasheet(PDF) 204 Page - Renesas Technology Corp