Numonyx™ Wireless Flash Memory (W18)
Figure 34: Protection Register Locking
0x88
User-Programmable
0x85
0x84
Intel Factory-Programmed
0x81
PR Lock Register 0
0x80
15 14 13 12 11 10 9
8
7
6
5
4
3
2
1
0
13.3
VPP Protection
The Numonyx™ Wireless Flash Memory (W18) provides in-system program and erase
at V
PP1
. For factory programming, it also includes a low-cost, backward-compatible
12 V programming feature.(Section
The EFP
feature can also be used to greatly improve factory program performance as explained
in
In addition to the flexible block locking, holding the V
PP
programming voltage low can
provide absolute hardware write protection of all flash-device blocks. If V
PP
is below
V
PPLK
, program or erase operations result in an error displayed in SR[3]. (See
Figure 35: Examples of VPP Power Supply Configurations
System supply
12 V supply
≤
10K
Ω
VCC
VPP
System supply
Prot# (logic signal)
VCC
VPP
•
12 V fast programming
•
Absolute write protection with V
PP
≤
V
PPLK
System supply
(Note 1)
12 V supply
•
Low-voltage programming
•
Absolute write protection via logic signal
System supply
VCC
VPP
VCC
VPP
•
Low voltage and 12 V fast programming
Note:
•
Low-voltage programming
If the V
CC
supply can sink adequate current, you can use an appropriately valued resistor.
November 2007
Order Number: 290701-18
Datasheet
77
NUMONYX [ NUMONYX B.V ]
