K9F4008W0A-TIB0 SAMSUNG [Samsung semiconductor], K9F4008W0A-TIB0 Datasheet - Page 22

• Manufacturer Part Number: K9F4008W0A-TIB0
• Description: 512K x 8 bit NAND Flash Memory
• Manufacturer: SAMSUNG [Samsung semiconductor]

READY/BUSY
The device has a R/B output that provides a hardware method of indicating the completion of a frame program, erase or read seek
completion. The R/B pin is normally high but transitions to low after program or erase command is written to the command register or
a random read is begin 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. Because pull-up resistor value is related to tr(R/B) and cur-
rent drain during busy(ibusy) , an appropriate value can be obtained with the following reference chart(Fig 10). Its value can be
determined by the following guidance.
Package Dimensions
V
CC
GND
Rp value guidance
Rp(min) =
where I
Rp(max) is determined by maximum permissible limit of tr
Device
L
is the sum of the input currents of all devices tied to the R/B pin.
V
CC
R/B
open drain output
(Max.) - V
I
OL
+ I
Rp
OL
100n
200n
L
300n
(Max.)
ibusy
=
Ready Vcc
3.3
1K
96
4.2
Fig 10 Rp vs tr ,tf & Rp vs ibusy
@ Vcc = 3.3V, Ta = 25
8mA + I
22
Ibusy
3.2V
tf
tr
L
tf
1.65
189
2K
4.2
0.8V
Rp(ohm)
C , C
290
1.1
3K
4.2
Busy
L
= 100pF
FLASH MEMORY
381
0.825
4.2
4K
tr
2m
3m
1m
2.0V