ade7566 Analog Devices, Inc., ade7566 Datasheet - Page 29

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

USING THE POWER SUPPLY FEATURES
In an energy meter application, the 3.3 V power supply (V
typically generated from the ac line voltage and regulated to
3.3 V by a voltage regulator IC. The preregulated dc voltage,
typically 5 V to 12 V, can be connected to V
resistor divider. A 3.6 V battery can be connected to V
Figure 32 shows how the ADE7566/ADE7569 power supply
inputs are set up in this application.
Figure 33 shows the sequence of events that occur if the main
power supply generated by the PSU started to fail in the power
meter application shown in Figure 32. The SAG detection can
provide the earliest warning of a potential problem on V
SAG LEVEL TRIP POINT
(240V, 220V, 110V TYPICAL)
SAGCYC = 1
AC INPUT
Figure 33. Power Supply Management Interrupts and Battery Switchover with Only V
V
P
2.75V
V
– V
1.2V
DCIN
V
DD
N
PSU
5V TO 12V DC
Figure 32. Power Supply Management for Energy Meter Application
REGULATOR
DCIN
3.3V
through a
BAT
V
BCTRL
DD
SWOUT
.
V
DD
V
SAG EVENT
.
BAT
(FSAG = 1)
DCIN
V
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), is
V
V
DD
N
P
64
45
49
50
60
61
58
DETECTION
SAG
When a SAG event occurs, user code can be configured to
backup data and prepare for battery switchover if desired. The
relative spacing of these interrupts depends on the design of the
power supply.
Figure 34 shows the sequence of events that occur if the main
power supply started to fail in the power meter application shown
in Figure 32, with battery switchover on low V
enabled.
Finally, the transition between V
Power Supply Modes (see the Operating Modes section) are
represented in Figure 35 and Figure 36.
SUPERVISORY
SUPERVISORY
VOLTAGE
VOLTAGE
V
(FVDCIN = 1)
DCIN
EVENT
t
1
DD
POWER SUPPLY
MANAGEMENT
IF SWITCHOVER ON LOW V
Enabled for Battery Switchover
t
2
AUTOMATIC BATTERY SWITCHOVER
V
SW
CONNECTED TO V
BSO EVENT
(FBSO = 1)
V
DD
SW
ADE7566/ADE7569
and V
(ADDR. 0xF8)
IPSMF SFR
DD
BAT
IS ENABLED,
BAT
and the different
DCIN
or low V
DD