K524G2GACB-A050 Datasheet, PDF (41/94 Pages) Samsung semiconductor – MCP MEMORY

K524G2GACB-A050
MCP MEMORY
4.8 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 com-
pletion. The R/B pin is normally high but transitions to low after program or erase command is written to the command register 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
Vcc
Rp _ibusy
R/B
open drain output
C_L
Ready Vcc
1.8V device - VOL : 0.1V, VOH : VCC-0.1V
VOH
VOL
Busy
tf
tr
Device
Figure 16. Rp vs tr ,tf & Rp vs ibusy
@ Vcc = 1.8V, Ta = 25°C , C_L = 30pF
200n
100n
1.70
Ibusy
2m
120
0.85
90
1m
tr
30
tf
1.7
60
1.7
0.57
1.7
0.43
1.7
1K
2K
3K
4K
Rp(ohm)
Rp value guidance
VCC(Max.) - VOL(Max.)
Rp(min, 1.8V part) =
=
IOL + ΣIL
1.85V
3mA + 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
- 41 -
Revision 1.3
November 2009