ade7566 Analog Devices, Inc., ade7566 Datasheet - Page 33

• Manufacturer Part Number: ade7566
• Description: Single-phase Energy Measurement Ic With 8052 Mcu, Rtc, And Lcd Driver
• Manufacturer: Analog Devices, Inc.

TRANSITIONING BETWEEN OPERATING MODES
The operating mode of the ADE7566/ADE7569 is determined
by the power supply connected to V
the power supply such as when V
or when V
section describes events that change the operating mode.
Automatic Battery Switchover (PSM0 to PSM1)
If any of the enabled battery switchover events occur (see the
Battery Switchover section), V
results in a transition from the PSM0 to PSM1 operating mode.
When battery switchover occurs, the analog circuitry used in
the ADE energy measurement DSP is disabled. To reduce power
consumption, the user code can initiate a transition to PSM2.
Entering Sleep Mode (PSM1 to PSM2)
To reduce power consumption when V
user code can initiate sleep mode, PSM2, by setting Bit 4 in the
Power Control SFR (POWCON, 0xC5) to shut down the MCU
core. Events capable of waking the MCU can be enabled (see the
3.3 V Peripherals and Wake-Up Events section).
Servicing Wake-Up Events (PSM2 to PSM1)
The ADE7566/ADE7569 may need to wake up from PSM2 to
service wake-up events (see the 3.3 V Peripherals and Wake-Up
Events section). PSM1 code execution begins at the power-on
reset vector. After servicing the wake-up event, the ADE7566/
ADE7569 can return to PSM2 by setting Bit 4 in the Power
Control SFR (POWCON, 0xC5) to shut down the MCU core.
Automatic Switch to V
If the conditions to switch V
Battery Switchover section), the operating mode switches to
PSM0. When this switch occurs, the MCU core and the analog
circuitry used in the ADE energy measurement DSP
automatically restarts. PSM0 code execution begins at the
power-on reset vector.
SW
switches to V
DD
DD
(PSM2 to PSM0)
SW
V
, alter the operating mode. This
SW
SW
from V
CONNECTED TO V
switches to V
NORMAL MODE
SW
PSMO
SW
switches from V
. Therefore, changes in
BAT
SW
is connected to V
to V
POWER SUPPLY
BAT
RESTORED
DD
DD
. This switchover
Figure 36. Transitioning Between Operating Modes
occur (see the
V
SW
AUTOMATIC BATTERY
DD
CONNECTED TO V
to V
SWITCHOVER
POWER SUPPLY
SLEEP MODE
RESTORED
PSM2
BAT
BAT
Rev. 0 | Page 33 of 136
,
,
BAT
WAKE-UP
EVENT
V
Automatic Switch to V
If the conditions to switch V
Battery Switchover section), the operating mode switches to
PSM0. When this switch occurs, the analog circuitry used in the
ADE energy measurement DSP automatically restarts. Note that
code execution continues normally. A software reset can be
performed to start PSM0 code execution at the power-on reset
vector.
USING THE POWER MANAGEMENT FEATURES
Because program flow is different for each operating mode, the
status of V
in the Peripheral Configuration SFR (PERIPH, 0xF4) indicates
what V
control program flow on wake-up. Because code execution
always starts at the power-on reset vector, Bit 6 of the PERIPH
SRF can be tested to determine which power supply is being
used and to branch to normal code execution, or to wake up
event code execution. Power supply events can also occur when
the MCU core is active. To be aware of the events that change
what V
•
•
An early warning that battery switchover is about to occur is
provided by SAG detection and possibly low V
(see the Battery Switchover section).
For a user-controlled battery switchover, enable automatic
battery switchover on low V
event to generate the PSM interrupt. When a low V
occurs, start data backup. Upon completion of the data backup,
enable battery switchover on low V
occurs 30 ms later.
SW
CONNECTED TO V
BATTERY MODE
Enable the battery switchover interrupt (EBSO)
if V
Enable the power supply restored interrupt (EPSR)
if V
SW
PSM1
SW
SW
SW
is connected to, use the following guidelines:
is connected to (see Table 19). This bit can be used to
SW
= V
= V
TO SHUTDOWN CORE AFTER
SERVICING WAKE-UP EVENT
must be known at all times. The VSWSOURCE bit
USER CODE DIRECTS MCU
DD
BAT
BAT
at power-up.
at power-up.
DD
(PSM1 to PSM0)
DD
SW
only. Then, enable the low V
from V
ADE7566/ADE7569
DCIN
BAT
. Battery switchover
to V
DD
DCIN
occur (see the
detection
DCIN
event
DCIN