71M6545 MAXIM [Maxim Integrated Products], 71M6545 Datasheet - Page 17

• Manufacturer Part Number: 71M6545
• Description: Four-Quadrant Metering, Phase Metrology Processors Flash/RAM Size
• Manufacturer: MAXIM [Maxim Integrated Products]

PDS_6545_009
the connection details) and are also routed though the multiplexer, as seen in
IADC2-IADC3, IADC4-IADC5 and IADC6-IADC7 current inputs are configured as remote sensor digital
interfaces and the corresponding samples are not routed through the multiplexer. For this configuration,
the multiplexer sequence is as shown in
For a poly-phase configuration with optional neutral current sensing using Current Transformer (CTs)
sensors, as shown in
to be connected to their corresponding CTs (see
IADC0-IADC1 current sensor input is optionally used to sense the Neutral current for anti-tampering
purposes. The voltage sensors (VADC8, VADC9 and VADC10) are directly connected to the 71M6545/H
(see
configuration and all sensors are routed through the multiplexer, as seen in
configuration, the multiplexer sequence is as shown in
The multiplexer sequence shown in
frame duration is 13 CK32 cycles (where CK32 = 32,768 Hz), therefore, the resulting sample rate is
32,768 Hz / 13 = 2,520.6 Hz. Note that
71M6545/H multiplexer, and does not show the currents that are copied directly into CE RAM from the
remote sensors (see
two unused conversion slots shown are necessary to produce the desired 2,520.6 Hz sample rate.
The multiplexer sequence shown in
Since in this case all current sensors are locally connected to the 71M6545/H, all currents are routed
through the multiplexer, as seen in
cycles (where CK32 = 32,768 Hz), therefore, the resulting sample rate is 32,768 Hz / 15 = 2,184.5 Hz.
Multiplexer advance, FIR initiation and chopping of the ADC reference voltage (using the internal CROSS
signal, see
MUX_CTRL launches each pass of the CE through its code. Conceptually, MUX_CTRL is clocked by
CK32, the 32768 Hz clock from the PLL block. The behavior of the MUX_CTRL circuit is governed by:
v1.0
Figure 23
MUX STATE
MUX STATE
MUX_SYNC
MUX_SYNC
1 Local / 3 Remotes:
CROSS
CROSS
2.2.7 Voltage
CK32
CK32
for the voltage sensor connection details). No 71M6xx3 isolated sensors are used in this
Figure
Figure
Figure 4: States in a Multiplexer Frame (MUX_DIV[3:0] = 6)
Figure 5: States in a Multiplexer Frame (MUX_DIV[3:0] = 7)
S
S
References) are controlled by the internal MUX_CTRL circuit. Additionally,
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2), which are sampled during the second half of the multiplexer frame. The
3, all four current sensor inputs must be configured as a differential inputs,
IA
IN
0
0
Figure
Figure
Figure 5
Unused
VA
Figure 4
1
1
Figure
3. For this multiplexer sequence, the frame duration is 15 CK32
4, covers the shunt configuration shown in
MUX_DIV[3:0]
MUX_DIV[3:0]
corresponds to the CT configuration shown in
Unused
4.
only shows the currents that pass through the
IB
Figure 25
2
2
Multiplexer Frame
Multiplexer Frame
Figure
VB
VA
3
3
= 6 Conversions
= 7 Conversions
for the differential CT connection details). The
5.
4
4
VB
IC
Figure
VC
VC
Figure
5
5
Data Sheet 71M6545/H
3. For this
Settle
S
2. Meanwhile, the
Figure
IN
6
Figure
2. The
Settle
S
3.
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