8. FUNCTIONAL DESCRIPTION
S1F76980 Technical Manual (Rev.1.0)
EPSON
11
(4) Power supply switching operation 1 (OFF-OFF switching)
Fig.8.4.3 shows an example of power supply switching operation 1 on connection / disconnection of power
supply with a higher priority level.
Description of each state
State A: Input power not selected.
(OB1:OFF, OB2:OFF, OU1:OFF, OU2:OFF, OC1:OFF, OC2:OFF)
State B: V
BAT
input power supply selected, backflow from V
OUT
prevented
(OB1:ON, OB2:OFF, OU1:OFF, OU2:OFF, OC1:OFF, OC2:OFF)
State C: V
BAT
input power supply selected, full on state
(OB1:ON, OB2:ON, OU1:OFF, OU2:OFF, OC1:OFF, OC2:OFF)
State D: V
CC
input power supply selected, backflow from V
OUT
prevented
(OB1:OFF, OB2:OFF, OU1:OFF, OU2:OFF, OC1:ON, OC2:OFF)
State E: V
CC
input power supply selected, full on state
(OB1:OFF, OB2:OFF, OU1:OFF, OU2:OFF, OC1:ON, OC2:ON)
Description of transition conditions
{
: V
CC
& V
BAT
input enabled
|
: V
CC
& V
BAT
input enabled, elimination of backflow potential between input power supply (V
CC
) and V
OUT
(Typ. 19mV)
}
: V
CC
& V
BAT
input enabled, backflow potential between input power supply (V
CC
) and V
OUT
~
: V
CC
input disabled, V
BAT
input enabled
: V
CC
input disabled, V
BAT
input enabled, elimination of backflow potential between input power supply
(V
BAT
) and V
OUT
(Typ. 19 mV)
: V
CC
input disabled, V
BAT
input enabled, backflow potential between input power supply (V
BAT
) and V
OUT
Fig.8.4.3 V
BAT
⇔
V
CC
power supply switching state transition 1
State C
State B
State E
State A
State D
