STPM11_08 STMICROELECTRONICS [STMicroelectronics], STPM11_08 Datasheet

no-image

STPM11_08

Manufacturer Part Number
STPM11_08
Description
Single phase energy metering IC with pulsed output and digital calibration
Manufacturer
STMICROELECTRONICS [STMicroelectronics]
Datasheet
Features
Description
The STPM1x family is designed for effective
measurement of active energy in a power line
system using a Rogowski Coil, current
transformer and shunt sensors. This device is
specifically designed to provide all the necessary
features to implement a single phase energy
meter without any other active component. The
STPM1x device family consists, essentially, of two
parts: the analog part and the digital part. The
former, is composed of a preamplifier and first
order ∑ Δ A/D converter blocks, band gap voltage
reference, low drop voltage regulator. The digital
part is composed of a system control, oscillator,
Table 1. Device summary
January 2008
Ripple free active energy pulsed output
Direct stepper counter drivers
Shunt, current transformer, Rogowsky coil
sensors
Live and neutral monitoring (STPM13/14)
Easy and fast digital calibration at only one
load point
No-load, negative power and tamper indicators
Integrated linear vregs
RC (STPM11/13) or crystal oscillator
(STPM12/14)
Support 50÷60 Hz - IEC62052-11, IEC62053-
2X specification
Less than 0.1% error
Order codes
STPM11ATR
STPM12ATR
STPM13ATR
STPM14ATR
Single phase energy metering IC with pulsed output
TSSOP20 (tape and reel)
TSSOP20 (tape and reel)
TSSOP20 (tape and reel)
TSSOP20 (tape and reel)
Package
Rev 5
hard wired DSP and interface for calibration and
configuration.
The calibration and configuration are done by
OTP cells, that can be programmed through a
serial interface. The configured bits are used for
testing, configuration and calibration purposes.
From two ∑ Δ output signals coming from the
analog section, a DSP unit computes the amount
of consumed active energy. The active energy is
available as a pulse frequency output and directly
driven by a stepper counter. In the STPM1x an
output signal with pulse frequency proportional to
energy is generated. This signal is used in the
calibration phase of the energy meter application
allowing a very easy approach. When the device
is fully configured and calibrated, a dedicated bit
of OTP block can be written permanently in order
to prevent accidental entry into test mode or
changing any configuration bit.
STPM11/12/13/14
and digital calibration
TSSOP20
2500 parts per reel
2500 parts per reel
2500 parts per reel
2500 parts per reel
Packaging
www.st.com
1/45
45

Related parts for STPM11_08

STPM11_08 Summary of contents

Page 1

Single phase energy metering IC with pulsed output Features ■ Ripple free active energy pulsed output ■ Direct stepper counter drivers ■ Shunt, current transformer, Rogowsky coil sensors ■ Live and neutral monitoring (STPM13/14) ■ Easy and fast digital calibration ...

Page 2

Contents 1 Schematic diagram 2 Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

Page 3

Mode signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

Page 4

List of figures Figure 1. Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

Page 5

List of tables Table 1. Device summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

Page 6

Schematic diagram Figure 1. Block diagram 6/45 ...

Page 7

Pin configuration Figure 2. Pin connections (top view) Table 1. Pin description Pin n° Symbol Type 1 MON MOP SCS OUT DDD 5 V GND ...

Page 8

Maximum ratings Table 2. Absolute maximum ratings (see note) Symbol V DC input voltage CC I Current on any pin (sink/source) PIN Input voltage at digital pins (SCS, MOP, MON, SYN, SDATD SCLNLC, LED) V Input voltage ...

Page 9

Electrical characteristics Table 4. Electrical characteristics ( 25°C, 2.2 µF between between V and V CC Symbol Parameter Energy measurement accuracy f Effective bandwidth BW Error Measurement error SNR Signal to ...

Page 10

Table 4. Electrical characteristics ( 25°C, 2.2 µF between between V and V CC Symbol Parameter Current injection latch-up I LATCH immunity Analog Inputs ( ...

Page 11

Table 4. Electrical characteristics ( 25°C, 2.2 µF between between V and V CC Symbol Parameter I Input current on CLKIN I R External resistor P C External capacitors P f Nominal ...

Page 12

Terminology 5.1 Measurement error The error associated with the energy measured by STPM1X is defined as: Percentage Error = [STPM1X (reading) - True Energy] / True Energy 5.2 ADC offset error This is the error due to the DC ...

Page 13

Typical performance characteristics Figure 3. Supply current vs supply voltage, T =25°C A Figure 5. RC oscillator: frequency jitter vs temperature Figure 7. Digital voltage regulator: line - load regulation Figure 4. RC Oscillator frequency vs V R=12 kΩ ...

Page 14

Figure 9. Power supply AC rejection vs V Figure 11. Error over dynamic range gain dependence Figure 13. Gain response of ΔΣ AD Converters Figure 14. Clock frequency vs external 14/45 Figure 10. Power supply DC rejection ...

Page 15

Theory of operation 7.1 General operation The STPM1X is able to perform active energy measurement (wide band or fundamental) in single-phase energy meter systems. Due to the proprietary energy computation algorithm, STPM1X active energy is not affected by any ...

Page 16

The Table 7 and Table Table 7. Configuration of current sensors Current channel Gain Table 8. Configuration of current sensors Primary Gain Sensor 8 16 Rogowsky Coil Both the ...

Page 17

The 1-bit DAC in the feedback loop is driven by the serial data stream. The DAC CLK output is subtracted from the input signal. If the loop gain is high enough, the average value of the DAC output ...

Page 18

V − IRMS BFR 6687 (Rogowsky) Where K is the voltage calibrator value ranging from 0.875 to 1.000. V The BFR flag is cleared when the V error is set, the computation of power is suspended and MOP, ...

Page 19

For example 783kΩ and R2 = 475Ω are used as resistor divider when the line voltage is present, the positive voltage present at the input of the voltage channel of STPM1x is ⋅ VI ...

Page 20

Figure 16. Bandgap temperature variation 7.7 Load monitoring The STPM1X include a no-load condition detection circuit with adjustable threshold. This circuit monitors the voltage and the current channels and, when the measured power is below the set threshold, the internal ...

Page 21

Error detection In addition to the no-load condition and the line frequency band, the integration of power can be suspended also due to detected error on the source signals. There are two kinds of error detection circuits involved. The ...

Page 22

Four periods before the primary to secondary switching point, a tamper detection module is activated deactivated after eight periods of line have elapsed. This means ...

Page 23

When internal signals are not good enough to perform the computation, i.e. line period is out or range or ∑ Δ signals from the analog part are stacked at high or low logic level load condition is activated, ...

Page 24

Figure 18. Different oscillator circuits (a); (b); (c) STPM12/14 with quartz 7.12 Resetting the STPM1x The STPM1x has no reset pin. The device is automatically reset by the POR circuit when the V crosses the 2.5 V value. When the ...

Page 25

Table 12. Different settings for led signal KMOT (2 Bits Due to the innovative and proprietary power calculation algorithm, the frequency signal is not affected by any ripple at twice the line frequency. This feature strongly ...

Page 26

Figure 19. Positive energy or absolute computation energy (ABS=1) stepper driving signals Figure 20. Negative energy stepper driving signals When a no-load condition is detected MOP and MON are held low. 7.15 Configuring the STPM1x All the configuration bits that ...

Page 27

The very first CFG bit, called TSTD, is used to disable any change of system signals after it has been permanently set. During the configuration phase, each bit set to logic level 1 increases the supply current of STPM01 of ...

Page 28

Table 14. Configuration bits map (continued) Address N. of Name 6-BIT bits DEC Binary 001010 10 FUND 1 001011 11 ABS 1 001100 12 LTCH 2 (1) 001101 13 001110 14 KMOT 2 (1) 001111 15 010010 18 BGTC 2 ...

Page 29

Table 14. Configuration bits map (continued) Address N. of Name 6-BIT bits DEC Binary 100000 32 100001 33 100010 34 100011 35 CHP 8 100100 36 100101 37 100110 38 (1) 100111 39 101000 40 101001 41 101010 42 101011 ...

Page 30

The mode signals bit can be written using the normal writing procedure of the CFGI interface (see CFGI par. 7.17) Table 15. Mode signals description Signal Bit Name Value 0 MOP and MON operate normally PUMP MOP and MON provide ...

Page 31

In this section, the SYN-NP, SCL-NLC and SDA-TD operation as part of the CFGI interface is described. – SYN-NP: this pin allows synchronization of the communication between STPM1x and the host. See – SCL-NLC ...

Page 32

CFGI out of idle state 1 2 → (>30ns): CFGI enabled for write operation data value is placed in SDA 3 t4: SDA value is stable and shifted into the ...

Page 33

SCS. The idle state of SCS would make the signal TSTD immediately effective which in turn, would abort the procedure and possibly destroy the device due to clearing ...

Page 34

Energy calculation algorithm Inside the STPM1x the computing section of the measured active power uses a completely new patented signal process approach. This approach allows the device to reach high performances in terms of accuracy. The signals, coming from ...

Page 35

I can then be used to calculate. These digital signals are also used in two additional steps for integration, obtaining: ⋅ dv/dt → v( sin tω; ...

Page 36

The signals process flow is the same as shown in the previous case, and even with the formulas above, the result ...

Page 37

STPM1x calibration Energy meters based on STPM1x devices are calibrated on the frequency of the output pulse signal. The devices are comprised of two independent meter channels for line voltage and current respectively. Each channel includes its own digital ...

Page 38

Each calibrator value can be changed from a binary form to a decimal correction form, using the following formula: Kv=(Cv/128)*0.125 + 0.75 and the same for Ki. Let us choose as initial value Ai=32 Table 18. Calibration results Description Value ...

Page 39

Schematic Figure 23. Charge pump schematic 39/45 ...

Page 40

Figure 24. Application schematic 40/45 ...

Page 41

Package mechanical data In order to meet environmental requirements, ST offers these devices in ECOPACK packages. These packages have a lead-free second level interconnect. The category of second Level Interconnect is marked on the package and on the inner ...

Page 42

Dim. Min 0.05 A2 0.8 b 0.19 c 0.09 D 6.4 E 6 0° PIN 1 IDENTIFICATION 1 42/45 TSSOP20 mechanical data mm. Typ. Max. 1.2 0.15 1 ...

Page 43

Tape & reel TSSOP20 mechanical data mm. Dim. Min. Typ 12 6.8 Bo 6.9 Ko 1.7 Po 3.9 P 11.9 inch. Max. Min. Typ. 330 13.2 0.504 0.795 2.362 22.4 7 0.268 ...

Page 44

Revision history Table 19. Document revision history Date Revision 30-Jan-2007 1 06-Feb-2007 2 20-Mar-2007 3 13-Sep-2007 4 21-Jan-2008 5 44/45 Changes Initial release. The Figure 11 has been changed. General description has been updated. Add Table 1 in cover ...

Page 45

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 ...

Related keywords