Backup And Recovery - Epson RX8900SA/CE Applications Manual

RX8900 SA / CE

8.10. Backup and Recovery

* tR1 is restrictions to validate power-on reset. When cannot keep this standard, power-on reset does not work
normally. It is necessary to initial setting by the software command.
Repeated ON/OFF of the power supply in short term, the power-on reset becomes unstable.
After power-OFF, keep a state of VDD=GND more than 60 seconds to validate power-on reset.
When it is impossible, please perform initial setting by the software command.
VDD
VBAT
2.5V
VDET
VLOW
VSS
tR1
CE
*1:VDD Voltage detection
Item
Detection voltage (1)
Detection voltage (2)
Detection voltage (3)
Power supply rise time1
Access wait time
(Initial power on)
Chip disable wait time
Power supply fall time
Power supply rise time2
Access wait time
( Normal power on)
*1
VIL VIL
tCL
Symbol Condition
VDET -
VLOW -
VDET3 -
tR1 VDD=VSS to 2.5V
tCL After VDD=2.5V
tCD After stop condition
tF VDD=2.5V to VSS
 VDD=VSS to 2.5V
tR2
After VDD=2.5V 
tCU
Page - 31
*1
VBAT<VDET
tF
tCD
Buck up operation
Min. Typ.
1.9 1.95
1.16
2.3
1
30
0
2
15
0
*1 *1
VBAT<VLOW
tR2
VIL
tCU
Max. Unit.
V
2.0
- 1.60 V
V
2.4 2.5
ms / V
- 10
ms
- -
 s / V
- -
 s / V
- -
 s / V
- -
 s
- -
ETM45E-01