ADE5166_08 AD [Analog Devices], ADE5166_08 Datasheet - Page 29

• Manufacturer Part Number: ADE5166_08
• Description: Single-Phase Energy Measurement IC with 8052 MCU, RTC, and LCD Driver
• Manufacturer: AD [Analog Devices]

SAG Monitor PSM Interrupt
The ADE5166/ADE5169 energy measurement DSP monitors
the ac voltage input at the V
register (Address 0x14) is used to set the threshold for a line
voltage SAG event. The FSAG bit in the power management
interrupt flag SFR (IPSMF, Address 0xF8) is set if the line voltage
stays below the level set in the SAGLVL register for the number
of line cycles set in the SAGCYC register (Address 0x13). See
the Line Voltage SAG Detection section for more information.
Setting the ESAG bit in the power management interrupt enable
SFR (IPSME, Address 0xEC) enables this event to generate a
PSM interrupt.
USING THE POWER SUPPLY FEATURES
In an energy meter application, the 3.3 V power supply (V
is 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
Table 26. Power Supply Event Timing Operating Modes
Parameter
t
t
t
t
1
2
3
4
(240V, 220V, 110V TYPICAL)
Time
10 ns min
10 ns min
30 ms typ
130 ms typ
AC INPUT
P
Description
Time between when V
Time between when V
Time between when V
battery switchover.
Time between when power supply restore conditions are met (V
BATPR[1:0] = 0b01 or V
and V
PSU
5V TO 12V DC
N
input pins. The SAGLVL
Figure 32. Power Supply Management for Energy Meter Application
DCIN
REGULATOR
3.3V
through a
DCIN
DD
DCIN
DD
falls below 2.75 V and when battery switchover occurs.
above 2.75 V if BATPR[1:0] = 0b00) and when V
BAT
goes below 1.2 V and when FVDCIN is raised.
falls below 1.2 V and when battery switchover occurs if V
V
BCTRL
.
SWOUT
DD
V
V
BAT
DCIN
V
Rev. 0 | Page 29 of 148
)
V
V
DD
N
P
45
49
50
64
60
61
58
DETECTION
Figure 32 shows how the ADE5166/ADE5169 power supply
inputs are set up in this application.
Figure 33 shows the sequence of events that occurs if the main
power supply generated by the PSU starts 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
When a SAG event occurs, user code can be configured to back
up data and prepare for battery switchover, if desired. The rela-
tive spacing of these interrupts depends on the design of the
power supply.
Figure 34 shows the sequence of events that occurs if the main
power supply starts 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.
SAG
SUPERVISORY
SUPERVISORY
VOLTAGE
VOLTAGE
POWER SUPPLY
DCIN
MANAGEMENT
above 1.2 V and V
SWOUT
switches to V
DD
V
SW
ADE5166/ADE5169
and V
DCIN
(ADDR. 0xF8)
IPSMF SFR
DD
is enabled to cause
BAT
above 2.75 V if
DD
and the different
.
DCIN
or low V
DD
.
DD