K9F2G08Q0M Datasheet, PDF (37/38 Pages) Samsung semiconductor – FLASH MEMORY

K9F2G08Q0M K9F2G16Q0M
K9F2G08U0M K9F2G16U0M
Preliminary
FLASH MEMORY
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 regis-
ter 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. Because pull-up resistor value is related to tr(R/B) and
current drain during busy(ibusy) , an appropriate value can be obtained with the following reference chart(Fig 17). Its value can be
determined by the following guidance.
VCC
GND
Rp _ibusy
R/B
open drain output
C_L
Ready Vcc
1.8V device - VOL : 0.1V, VOH : VccQ-0.1V
3.3V device - VOL : 0.4V, VOH : 2.4V
VOH
VOL
Busy
tf
tr
Device
Figure 17. Rp vs tr ,tf & Rp vs ibusy
@ Vcc = 1.8V, Ta = 25°C , C_L = 30pF
@ Vcc = 3.3V, Ta = 25°C , C_L = 50pF
300n
Ibusy
2.4
200
Ibusy
3m
150n
1.2
150
3m
200n
1.7
tr ^0.85
90
120
2m
100n
100
0.8
tr
2m
100n
30
60
1.7 _tf
1.7
0.57
1.7
0.43
1.7
1m
50n
50
0.6
1m
1.8 _tf
1.8
1.8
1.8
1K
2K
3K
4K
Rp(ohm)
1K
2K
3K
4K
Rp(ohm)
Rp value guidance
VCC(Max.) - VOL(Max.)
Rp(min, 1.8V part) =
=
IOL + ΣIL
1.85V
3mA + ΣIL
VCC(Max.) - VOL(Max.)
Rp(min, 3.3V part) =
=
IOL + ΣIL
3.2V
8mA + ΣIL
where IL is the sum of the input currents of all devices tied to the R/B pin.
Rp(max) is determined by maximum permissible limit of tr
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