Cypress STK22C48 Computer Hardware User Manual


 
STK22C48
Document Number: 001-51000 Rev. ** Page 10 of 14
AutoStore or Power Up RECALL
Parameter Alt Description
STK22C48
Unit
Min Max
t
HRECALL
[12]
t
RESTORE
Power up RECALL Duration 550 μs
t
STORE
[14, 15]
t
HLHZ
STORE Cycle Duration 10 ms
t
DELAY
[13]
t
HLQZ ,
t
BLQZ
Time Allowed to Complete SRAM Cycle 1 μs
V
SWITCH
Low Voltage Trigger Level 4.0 4.5 V
V
RESET
Low Voltage Reset Level 3.6 V
t
VSBL
[10]
Low Voltage Trigger (V
SWITCH
) to HSB Low 300 ns
Switching Waveform
Figure 11. AutoStore/Power Up RECALL
WE
Notes
12.t
HRECALL
starts from the time V
CC
rises above V
SWITCH
.
13.CE
and OE low for output behavior.
14.CE
and OE low and WE high for output behavior.
15.HSB
is asserted low for 1us when V
CAP
drops through V
SWITCH
. If an SRAM Write has not taken place since the last nonvolatile cycle, HSB is released and no store
takes place.
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