STEVAL-IPE008V1 STMicroelectronics, STEVAL-IPE008V1 Datasheet - Page 22

• Manufacturer Part Number: STEVAL-IPE008V1
• Description: BOARD EVAL STPM01/STR715FR0
• Manufacturer: STMicroelectronics
• Type: Other Power Managementr

Specifications of STEVAL-IPE008V1

• Main Purpose: Power Management, Energy/Power Meter
• Embedded: Yes, MCU, ARM7
• Utilized Ic / Part: STPM01, STR715FR0
• Primary Attributes: 3-Ph Energy Meter (or Single Phase)
• Secondary Attributes: Measures Active, Reactive, Apparent Power
• Product: Power Management Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: STPM01, STR715FR0
• Other names: 497-6412; STEVAL-IPE008V1

Theory of operation
Table 10.
8.7
22/60
for tampering purposes or in case the line voltage is very stable, it is possible to use a
predefined value for computing the energy without sensing it.
In order to enable the SWM mode, the STPM01 must be configured with PST values of 4 or
5, (tamper enabled-Rogowsky coils). In this way, if the BFR error is detected, STPM01
enters in SWM. If BFR is cleared the energy calculation is performed normally, when BFR is
set (no voltage information is available) the energy computation is carried out using a
nominal voltage value according to the NOM configuration bits.
Since there is no more information on the phase shift between voltage and current, the
apparent rather than active power is used for tamper and energy computation. The
calculated apparent energy is the product between I
equivalent V
V
where V
coefficient that changes according to the following table:
Nominal voltage values
For example, if a R
voltage is present, the positive voltage present at the input of the voltage channel of
STPM01 is:
since the maximum voltage value applicable to the voltage channel input of STPM01 is +0.3
V, the equivalent maximum line voltage applicable is:
V
considering the case of NOM=2, the correspondent RMS values used for energy
computation are:
V
Usually the supply voltage for the electronic meter is taken from the line voltage, in SWM,
since the line voltage is not present any more, some other power source must be used in
order to provide the necessary supply to STPM01 and the other electronic components of
the meter.
Power supply
The main STPM01 supply pin is the V
the necessary voltage for the analog part V
The V
VI
RMS
PK
RMS
=
= R
R
= V
SS
= V
1
R
1
+
PK
pin represents the reference point for all the internal signals. 100 nF low ESR
+R
2
PK
PK
R
NOM
represents the maximum line voltage reading of the STPM01 and K
2
*K
0
1
2
3
2
RMS
• 0.4219 = 208.76 [V]
/R
⋅
NOM
V
2
RMS
that can be calculated as follows:
• 0.3 = 494.82
,
1
= 783 kΩ and R
2
Doc ID 10853 Rev 7
2
CC
= 475 Ω are used as resistor divider when the line
pin. From the V
DDA
(3 V) and for the digital part V
RMS
CC
(effectively measured) and an
pin two linear regulators provide
0.3594
0.3906
0.4219
0.4531
K
NOM
DDD
NOM
(1.5 V).
STPM01
is a