k9f6408u0a Samsung Semiconductor, Inc., k9f6408u0a Datasheet - Page 25

• Manufacturer Part Number: k9f6408u0a
• Description: 8m X 8 Bit Nand Flash Memory
• Manufacturer: Samsung Semiconductor, Inc.

Figure 11. AC Waveforms for Power Transition
DATA PROTECTION
The device is designed to offer protection from any involuntary program/erase during power-transitions. An internal voltage detector
disables all functions whenever Vcc is below about 2V. WP pin provides hardware protection and is recommended to be kept at V
during power-up and power-down as shown in Figure 11. The two step command sequence for program/erase provides additional
software protection.
READY/BUSY
The device has a R/B output that provides a hardware method of indicating the completion of a page program, erase and random
read completion. The R/B pin is normally high but transitions to low after program or erase command is written to the command reg-
ister or random read is started after address loading. It returns to high when the internal controller has finished the operation. The pin
is an open-drain driver thereby allowing two or more R/B outputs to be Or-tied. An appropriate pull-up resister is required for proper
operation and the value may be calculated by the following equation.
K9F6408U0A-TCB0, K9F6408U0A-TIB0
V
WP
CC
V
CC
GND
Device
~ 2.5V
R/B
open drain output
Rp
High
25
where I
R/B pin.
Rp =
L
V
is the sum of the input currents of all devices tied to the
CC
(Max.) - V
I
OL
+ I
OL
L
(Max.)
FLASH MEMORY
=
~ 2.5V
8mA + I
3.2V
L
IL