STEVAL-IPE012V1 STMicroelectronics, STEVAL-IPE012V1 Datasheet
STEVAL-IPE012V1
Specifications of STEVAL-IPE012V1
Related parts for STEVAL-IPE012V1
STEVAL-IPE012V1 Summary of contents
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Features ■ Measures active, reactive, and apparent energies ■ Current, voltage RMS and instantaneous measurement ■ Frequency measurement ■ Ripple-free active energy pulsed output ■ Live and neutral monitoring for tamper detection ■ Fast and simple one-point digital calibration over ...
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Contents Contents 1 Schematic diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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STPM10 7.14 Energy to frequency conversion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 7.15 ...
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List of tables List of tables Table 1. Device summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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STPM10 List of figures Figure 1. Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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Schematic diagram 1 Schematic diagram Figure 1. Block diagram Voltage Ref VCC + VIP ΔΣ A VIN Gain: 8-32 + IIPI Tamper - IIN1 Gain: 8-32 + IIP2 - IIN2 VSS 6/51 VDDA VDDD Linear Vregs 56-bit Configurators ...
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STPM10 2 Pin configuration Figure 2. Pin connections (top view) Table 2. Pin description (1) Pin Symbol Type 1 WDG ZCR SCS OUT DDD 5 V GND SS 6 ...
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Maximum ratings 3 Maximum ratings Table 3. Absolute maximum ratings Symbol V DC input voltage CC I Current on any pin (sink/source) PIN Input voltage at digital pins (SCS, ZCR, WDG, SYN, SDA SCL, LED) V Input voltage ...
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STPM10 4 Electrical characteristics °C,100 µF between and V , 100 µF between V SS Table 5. Electrical characteristics Symbol Parameter Energy measurement accuracy ...
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Electrical characteristics Table 5. Electrical characteristics (continued) Symbol Parameter V Amplifier offset OFF impedance impedance IN IP1 IN1 IP2 IN2 G Current channels gain error ...
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STPM10 Table 5. Electrical characteristics (continued) Symbol Parameter F Data write speed SCLKw t Data setup time DS t Data hold time DH t Data driver on time ON t Data driver off time OFF t SYN active width SYN ...
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Terminology 5 Terminology 5.1 Measurement error The error associated with the energy measurement made by the STPM10 is defined as: Percentage error = [STPM10 (reading) - true energy] / true energy 5.2 ADC offset error This is the error due ...
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STPM10 6 Typical performance characteristics Figure 3. Supply current vs. supply voltage ° 4.194MHz, 8.192MHz) A Figure 5. RC oscillator: frequency jitter vs. temperature Figure 7. Digital voltage regulator: line - load regulation Typical performance ...
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Typical performance characteristics Figure 9. Power supply AC rejection vs. V Figure 11. Error over dynamic range gain dependence Figure 13. Gain response of ΔΣ A/D converters 14/51 Figure 10. Power supply DC rejection vs Figure 12. Primary ...
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STPM10 7 Theory of operation 7.1 General operation description The STPM10 is capable of performing measurements of active, reactive and apparent energy, RMS and instantaneous voltage and current values, and line frequency information. Most of the functions are fully programmable ...
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Theory of operation Table 6. Gain of voltage and current channels Voltage channels Gain 4 The gain register is included in the device configuration register with the address name PST. The table below shows the gain configuration according to the ...
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STPM10 integration and DC offset cancellation of the supplied Σ Δ signals. The gain of the decimation filters is 1.004 for the voltage channel and 0.502 for the current channel. The resulting signal has a resolution of 11 bits per ...
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Theory of operation 7.5 Period and line voltage measurement The period module measures the period of the base frequency of the voltage channel and checks if the voltage signal frequency is within the f LIN signal is produced, which is ...
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STPM10 With the same clock frequency, if the line frequency is 130 Hz, the f two LIN trailing edges are 8066, less than 4194304/32768 = 128 Hz. CLK The BFR flag is also set if ...
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Theory of operation 7.7 Load monitoring The STPM10 includes a no-load condition detection circuit with adjustable threshold. This circuit monitors the voltage and the current channels and, when the measured voltage is below the set threshold, the internal signal BIL ...
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STPM10 energy values is greater than a certain percentage of the averaged energy during the activated tamper module (see This percentage value can be selected between two different values (12.5 % and 6.25 %) according to the value of the ...
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Theory of operation When the secondary channel is selected to be integrated by the final energy integrator, the MUX and INH signals change according to Figure 19. Timings of tamper module - Secondary channel selected This means that energy of ...
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STPM10 1. RC: this oscillator mode can be selected using the RC configuration bit the STPM10 runs using the RC oscillator. A resistor connected between CLKIN and ground sets the RC current. For 4 MHz operation, ...
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Theory of operation 7.12 Resetting the STPM10 The STPM10 has no reset pin. The device is automatically reset by the POR circuit when the V crosses the 2.5 V value, but it can also be reset through the SPI interface ...
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STPM10 taken from the 11 between the LSB value of the active energy register and the number of pulses provided per each kWh (P) can be defined as: Equation 1000 = ⋅ ...
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Theory of operation 7.15 Status bits The STPM10 includes 8 status bits which provide information about the current status of the meter. The status bits are the following: Table 10. Status bit description Bit # Name Description 0 BIL No-load ...
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STPM10 7.16 Programming the STPM10 7.16.1 Data records The STPM10 has 8 internal data record registers. Every data record consists of a 4-bit parity code and 28-bit data value where the parity code is computed from the data value, which ...
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Theory of operation Each configuration bit can be written by sending a byte command to STPM10 through its SPI interface. The procedure to write the configuration bits is described in interface . Table 11. Configuration bit map Address n. of ...
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STPM10 Table 11. Configuration bit map (continued) Address n. of Name 6-bit bits DEC binary 010000 010001 010010 18 BGTC 2 (1) 010011 19 010100 20 010101 21 CPH 4 010110 22 (1) 010111 ...
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Theory of operation Table 11. Configuration bit map (continued) Address n. of Name 6-bit bits DEC binary 110000 48 CRC 2 (1) 110001 49 110010 110011 110100 110101 53 CRIT 1 ...
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STPM10 Table 12. Mode signal description (continued) 0 Current channel 1 selected when tamper is disabled 4 CSEL 1 Current channel 2 selected when tamper is disabled 5 Reserved 6 Reserved Swap the 32-bit data record readings. From 7 Precharge ...
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Theory of operation clock signal. When SCS is high, SCL is also high, determining the idle state of the SPI. – SDA: the data pin. If SCS is low, the operation of SDA is dependent on the status of the ...
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STPM10 7.21 Reading data records A microcontroller is able to read all measurement results and all system signals (configuration, calibration, status, mode). Again, the time step can be as short as 30 ns. There are two phases of reading, called ...
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Theory of operation Figure 24. Timing for data record reading SCS SCS SYN SYN SCLNLC SCLNLC SDATD SDATD → Latching phase. Interval value > 2 → Data ...
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STPM10 1 bit DATA value+6-bits address+1 bit ( depicted in binary command is 01011111 (0x5F), which is the one depicted, or 01011110 (0x5E): Figure 25. Timing for writing configuration and mode bits → ...
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Theory of operation 7.22.1 Interfacing the standard 3-wire SPI with the STPM10 SPI Due to the fact that a 2-wire SPI is implemented in the STPM10 clear that sending any command from a standard 3-wire SPI would require ...
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STPM10 where I is the peak current, between voltage and current. 7.23.1 Active power In the STPM10, after the pre-conditioning and the A/D conversion, the digital voltage signal (which is dynamically more stable with respect to the current signal) is ...
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Theory of operation Figure 26. Active energy computation diagram At this point four signals are available. By combining (pairing) them by means of two multiplying stages, two results are obtained: Equation 11 dv ∫ = ⋅ ...
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STPM10 Equation 13 − [see Figure 26 - 11] In this way, the AC part V•I•cos(2 power. The absence of any AC component allows for ...
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Theory of operation 1 = ⋅ The reactive power, then, presents a ripple at twice the line frequency. Since the average value of a sinusoid is 0, this ripple ...
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STPM10 ⋅ ω ⋅ S ω ⋅ The DSP then performs the integration of the computed powers into energies. These integrators are implemented as up/down counters and they can roll over. 20-bit output buses of ...
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Theory of operation Table 14. Device constants Parameter Internal reference voltage Internal calculation frequency Amplification of voltage ADC Amplification of current ADC Gain of differentiator Gain of integrator Gain of decimation filter RMS voltage record length RMS current record length ...
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STPM10 The calibration procedure outputs C of the meter. This sensitivity is used to calculate target frequency at the LED pin for nominal voltage and current values: with: From the values above and for both chosen amplification factor A data, ...
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Application design 8 Application design The choice of the external components in the transduction section of the application is a crucial point in the application design, affecting the precision and the resolution of the whole system. Among the several considerations, ...
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STPM10 Figure 27. STPM10 reference schematic with one current transformer and one shunt Doc ID 17728 Rev 3 Application design 45/51 ...
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Package mechanical data 9 Package mechanical data In order to meet environmental requirements, ST offers these devices in different grades of ® ECOPACK packages, depending on their level of environmental compliance. ECOPACK specifications, grade definitions and product status are available ...
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STPM10 Dim. Min 0.05 A2 0.8 b 0.19 c 0.09 D 6.4 E 6 0° PIN 1 IDENTIFICATION 1 TSSOP20 mechanical data mm. Typ. Max. 1.2 0.15 1 ...
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Package mechanical data Tape & reel TSSOP20 mechanical data Dim. Min 12 6.8 Bo 6.9 Ko 1.7 Po 3.9 P 11.9 48/51 mm. Typ. Max. Min. 330 13.2 0.504 0.795 2.362 22.4 ...
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STPM10 Figure 28. TSSOP20 footprint recommended data Table 17. Footprint data Values mm. 7.26 4.93 0.36 0.65 6.21 Doc ID 17728 Rev 3 Package mechanical data inch. 0.286 0.194 0.014 0.025 0.244 49/51 ...
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Revision history 10 Revision history Table 18. Document revision history Date Revision 31-Aug-2010 1 25-Nov-2010 2 09-Jun-2011 3 50/51 Initial release. Modified: Table 5 on page 9, 7.9: Tamper detection module on page Added: 7.11.1: RC startup procedure on page ...
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... STPM10 Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale. ...