S1F78100Y2A Epson Electronics America, Inc., S1F78100Y2A Datasheet - Page 71

• Manufacturer Part Number: S1F78100Y2A
• Description: High Precision Voltage Regulators
• Manufacturer: Epson Electronics America, Inc.

S1F76540 Series
Power-off Control Function
The S1F76540 has the power-off function and turns on
or off each circuit function when control signals are en-
tered in the P
tem (such as microprocessor) as defined on Table 2.7.
This power-off function can also cut the reactive current
Table 2.7 Available combination of power-off control
*1 When the booster circuit is off, approximately V
*2 When the regulator is off, the V
Application notes on power-off function:
2–28
Mode
• When using external system signals for power-on control, start to control the power only when V
PS1
PS2
PS3
PS4
becomes stable after power-on. Unstable V
P
P
OFF1
OFF2
(High = V
(Low = V
OFF1
V
P
High
High
Low
Low
I
OFF1
and P
DD
I
) (Low = V
) (High = V
OFF2
P
High
High
Low
Low
OFF2
pins from an external sys-
Figure 2.6 Start timing of power-off control
DD
I
)
) Oscillator Booster Regulator
REG
OFF
OFF
ON
ON
pin becomes high-impedance state.
Functions
I
OFF (*1) OFF (*2) All circuits are turned off.
voltage may destroy the IC permanently during on/off control.
circuit
ON
ON
ON
EPSON
I
+ 0.6 V voltage appears at V
P
P
in parallel connection and other application circuits.
To use the dual-state, power-off control (all ON and all
OFF states) only, connect pin P
only pin P
OFF1
OFF2
circuit
V
OFF
ON
ON
I
OFF1
All circuits are turned on.
Slave unit side of parallel connection
(Booster and regulator)
Master unit side of parallel
connection (Booster only)
for power-off control.
Applications
O
OFF2
pin.
to pin V
Technical Manual
S1F70000 Series
I
I
and use
voltage