Datasheet

Section 22 PROM
Rev. 6.00 Mar. 18, 2010 Page 759 of 982
REJ09B0054-0600
22.3 Programming
Table 22.3 shows how to select the program, verify, and other modes in PROM mode.
Table 22.3 Mode Selection in PROM Mode
Pins
Mode CE OE PGM VPP VCC EO7 to EO0 EA16 to EA0
Program L H L V
PP
V
CC
Data input Address input
Verify L L H V
PP
V
CC
Data output Address input
Programming prohibited L L L V
PP
V
CC
High impedance Address input
L H H
H L L
H H H
Legend:
L: Low voltage level
H: High voltage level
V
PP
: V
PP
voltage level
V
CC
: V
CC
voltage level
Programming and verification should be carried out using the same specifications as for the
standard HN27C101 EPROM.
However, do not set the PROM programmer to page mode does not support page programming. A
PROM programmer that only supports page programming cannot be used. When choosing a
PROM programmer, check that it supports high-speed programming in byte units. Always set
addresses within the range H'00000 to H'1FFFF.
22.3.1 Programming and Verification
An efficient, high-speed programming procedure can be used to program and verify PROM data.
This procedure writes data quickly without subjecting the chip to voltage stress or sacrificing data
reliability. It leaves the data H'FF in unused addresses. Figure 22.4 shows the basic high-speed
programming flowchart. Tables 22.4 and 22.5 list the electrical characteristics of the chip during
programming. Figure 22.5 shows a timing chart.