ade7169f16 Analog Devices, Inc., ade7169f16 Datasheet - Page 44

• Manufacturer Part Number: ade7169f16
• Description: Single-phase Energy Measurement Ic With 8052 Mcu, Rtc And Lcd Driver
• Manufacturer: Analog Devices, Inc.

ADE7169F16
Voltage Channel ADC
Figure 21 shows the ADC and signal processing chain for the
Voltage Channel. In waveform sampling mode, the ADC
outputs a signed twos complement 24-bit data-word at a
Channel Sampling
The waveform samples of the current ADC and voltage ADC
can also be routed to the waveform registers to be read by the
MCU core. The active, reactive, apparent power, and energy
calculation remain uninterrupted during waveform sampling.
When in waveform sampling mode, one of four output sample
rates can be chosen by using Bits 0 and 1 of the WAVMODE
register (WAVSEL1,0). The output sample rate can be 25.6 kSPS,
12.8kSPS, 6.4 kSPS, or 3.2 kSPS—see Table 30. If the WFSM
enable bit is set in the Interrupt Enable Register 3 SFR
(MIRQENH, 0xDB), the 8052 core has a pending ADE
interrupt. The sampled signals selected in the WAVMODE
register will be latched into the Waveform SFRs when the
waveform high byte (WAV1H or WAV2H) is read.
The ADE interrupt stays active until the WFSM status bit is
cleared—see Energy measurement interrupts section.
FAULT DETECTION
The ADE7169F16 incorporates a fault detection scheme that
warns of fault conditions and allows the ADE7169F16 to
continue accurate measurement during a fault event. The
ADE7169F16 does this by continuously monitoring both
current inputs (IA and IB). These currents will be referred for
0.5V, 0.25V,
0.125V, 62.5mV,
31.3mV
V2
0V
VP
V2
ANALOG
INPUT
RANGE
PGA2
x1, x2, x4,
x8, x16
{GAIN[7:5]}
Figure 22. ADC and Signal Processing in Voltage Channel
0xD70B
0x28F5
REFERENCE
0x0000
ADC
VOLTAGE CHANNEL
WAVEFORM
DATA RANGE
Rev. PrD | Page 44 of 140
HPF
ACTIVE AND REACTIVE
POWER CALCULATION
f
–
maximum of 25.6 kSPS (MCLK/160). The ADC produces an
output code that is approximately between 0x28F5 (+10,485d)
and 0xD70B (–10,485d)—see Figure 22.
ease of understanding as phase and neutral (return) currents. In
the ADE7169F16, a fault condition is defined when the
difference between I
channel. If a fault condition is detected and the inactive channel
is larger than the active channel, the ADE7169F16 automatically
switches to current measurement to the inactive channel.
During a fault, the active, reactive, current rms and apparent
powers are generated using the larger of the two currents. On
power-up, I
and Apparent power and Irms calculations.
To prevent false alarm, averaging is done for the fault detection
and a fault condition is detected approximately 1 second after
the event. The fault detection is automatically disabled when the
voltage signal is less than 0.3% of the full-scale input range. This
eliminates false detection of a fault due to noise at light loads.
Because the ADE7169F16 looks for a difference between the
voltage signals on I
transducers be closely matched.
Channel selection Indication
The current channel selected for measurement is indicated by
bit 7 (ICHANNEL) in the ACCMODE register (0x0F). When
this bit is cleared, I
MODE1[6]
3dB
VOLTAGE RMS (VRMS)
CALCULATION
WAVEFORM SAMPLE
REGISTER
VOLTAGE PEAK DETECT
LPF1
= 63.7Hz
A
is the current input selected for Active, Reactive,
0x1DD0
0xE230
0xDFC9
ZX DETECTION
0x0000
0x2037
0x0000
A
A
A
is selected and when it is set, I
and I
Preliminary Technical Data
and I
ZX SIGNAL
DATA RANGE for 60Hz signal
ZX SIGNAL
DATA RANGE for 50Hz signal
B
, it is important that both current
B
is greater than 6.25% of the active
B
is selected.