Features
 Active power accuracy:
– < 0.1% error over 5000: 1 dynamic range
– < 0.5% error over 10000: 1 dynamic range
 Exceeds 50-60 Hz EN 50470-x, IEC 62053-2x,
ANSI12.2x standard requirements for AC watt
meters
 Reactive power accuracy:
– < 0.1% error over 2000:1 dynamic range
 Dual mode apparent energy calculation
 Instantaneous and averaged power
 RMS and instantaneous voltage and current
 Under and overvoltage detection (sag and
swell) and monitoring
 Overcurrent detection and monitoring
 UART and SPI serial interface with
programmable CRC polynomial verification
 Programmable LED and interrupt outputs
 Four independent 24-bit 2nd order sigma-delta
ADCs
 Two programmable gain chopper stabilized
low-noise and low-offset amplifiers
 Bandwidth 3.6 kHz at -3 dB
 Vcc supply range 3.3 V ± 10%
 Supply current Icc 4.3 mA (STPM32)
 Input clock frequency 16 MHz, Xtal or external
source
 Twin precision voltage reference: 1.18 V with
independent programmable TC, 30 ppm/°C
typ.
 Internal low drop regulator at 3 V (typ.)
 QFN packages
 Operating temperature from -40 °C to +105 °C

Description
The STPM3x is an ASSP family designed for high
accuracy measurement of power and energies in
power line systems using the Rogowski coil,
current transformer or shunt current sensors. The
STPM3x provides instantaneous voltage and
current waveforms and calculates RMS values of
voltage and currents, active, reactive and
apparent power and energies. The STPM3x is a
mixed signal IC family consisting of an analog and
a digital section. The analog section consists of
up to two programmable gain low-noise low-offset
amplifiers and up to four 2nd order 24-bit sigmadelta
ADCs, two bandgap voltage references with
independent temperature compensation, a low
drop voltage regulator and DC buffers. The digital
section consists of digital filtering stage, a
hardwired DSP, DFE to the input and a serial
communication interface (UART or SPI). The
STPM3x is fully configurable and allows a fast
digital system calibration in a single point over the
entire current dynamic range.