4554 Datasheet, PDF (135/138 Pages) Renesas Technology Corp – SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER

4554 Group
(1) PROM mode
The built-in PROM version has a PROM mode in addition to a nor-
mal operation mode. The PROM mode is used to write to and read
from the built-in PROM.
In the PROM mode, the programming adapter can be used with a
general-purpose PROM programmer to write to or read from the
built-in PROM as if it were M5M27C256K.
Programming adapter is listed in Table 26. Contact addresses at
the end of this data sheet for the appropriate PROM programmer.
• Writing and reading of built-in PROM
Programming voltage is 12.5 V. Write the program in the PROM of
the built-in PROM version as shown in Figure 62.
(2) Notes on handling
➀A high-voltage is used for writing. Take care that overvoltage is
not applied. Take care especially at turning on the power.
➁For the One Time PROM version shipped in blank, Renesas
Technology corp. does not perform PROM writing test and
screening in the assembly process and following processes. In
order to improve reliability after writing, performing writing and
test according to the flow shown in Figure 63 before using is rec-
ommended (Products shipped in blank: PROM contents is not
written in factory when shipped).
(3) Difference between Mask ROM version and
One Time PROM version
Mask ROM version and One Time PROM version have some differ-
ence of the following characteristics within the limits of an electrical
property by difference of a manufacture process, built-in ROM, and
a layout pattern.
• a characteristic value
• a margin of operation
• the amount of noise-proof
• noise radiation, etc.,
Accordingly, be careful of them when swithcing.
Table 26 Programming adapter
Part number
Name of Programming Adapter
M34554EDFP
PCA7448
Address
000016
1
11
D4 D3 D2 D1 D0
Low-order 5 bits
3FFF16
400016 ₁
11
D4 D3 D2 D1 D0
High-order 5 bits
7FFF16
Fig. 62 PROM memory map
Writing with PROM programmer
Screening (Leave at 150 °C for 40 hours) (Note)
Verify test with PROM programmer
Function test in target device
Note: Since the screening temperature is higher
than storage temperature, never expose the
microcomputer to 150 °C exceeding 100
hours.
Fig. 63 Flow of writing and test of the product shipped in blank
Rev.3.00 Aug 06, 2004 page 135 of 136
REJ03B0043-0300Z