STMicroelectronics STPMS2L-PUR

Overview

STPMS2L-PUR from STMicroelectronics is a dual-channel, second-order sigma-delta modulator with integrated chopper-stabilized programmable-gain amplifier and 1.23 V temperature-compensated bandgap reference. It delivers <0.5% error over 1:5000 dynamic range, supports 4 MHz clock input, and is designed for high-accuracy AC watt-metering using Rogowski coils, current transformers, or shunt sensors in single- or multi-phase energy meters.

For engineers reviewing the STPMS2L-PUR datasheet, STPMS2L-PUR pinout, STPMS2L-PUR application, or STPMS2L-PUR equivalent, key selection criteria include its dual ΣΔ channel architecture, ±20 mV amplifier offset, 120 dB PSRRDC, 82 dB SNR (current channel), and compliance with IEC 62053-21/22/23 Class 0.2 standards.

Technical Context

The STPMS2L-PUR integrates two independent second-order sigma-delta modulators-one for current (CIP/CIN) and one for voltage (VIP/VIN)-each with dedicated analog front-end gain control and non-overlapping clock generation. Its chopper-stabilized PGLNA provides programmable gain (2x–16x), low offset (<±20 mV), and 118–120 dB noise floor depending on gain setting.

Digital operation includes hard mode (fixed configuration), soft mode (SPI-configurable via MS0–MS3), and BIST support. The device outputs time-multiplexed bitstreams (DAT/DATn) synchronized to an external 4.19 MHz clock, with latency of 40 ns and effective bandwidth up to 4 kHz in high-precision mode.

Key Specifications

Pinout & Package

STPMS2L-PUR is housed in a thermally enhanced QFN16 package (4 mm × 4 mm, 0.5 mm pitch) with exposed thermal pad for improved power dissipation in metering applications.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-channel sigma-delta modulator applications.

Compared with AMC1305M05DWR and AD7403BRIZ-RL, the STPMS2L-PUR uniquely integrates dual ΣΔ channels, chopper-stabilized PGA, 1.23 V reference, and 3 V LDO in one QFN16 package-reducing BOM count and PCB area in Class 0.2 metering and multi-sensor industrial systems.

Availability

STPMS2L-PUR is available at Aetrix Electronics and suitable for smart electricity meters, industrial motor control systems, and precision weight scale instrumentation requiring stable component supply and long-term metrology-grade performance.

Supply support for STPMS2L-PUR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, specializing in automotive, industrial, and power management ICs with strong metrology and mixed-signal design heritage.

The STPMS2 product line targets high-accuracy electrical parameter measurement-specifically enabling Class 0.2–0.5 revenue-grade energy meters and industrial sensor interfaces with integrated analog front-end functionality.

FAQ

What is the maximum recommended clock frequency for STPMS2L-PUR in high-precision mode?

The STPMS2L-PUR supports a nominal clock frequency of 4.19 MHz in high-precision mode, delivering an effective signal bandwidth of 0–4 kHz. This frequency is specified in the datasheet (Table 5) and validated for metrology-grade performance including 82 dB SNR and <0.5% error over 1:5000 range. Operation above 4.915 MHz is not guaranteed and may degrade INL/DNL or increase jitter-induced noise.

Does STPMS2L-PUR require external components for basic operation?

Yes-STPMS2L-PUR requires external 1 µF ceramic capacitors on VCC, VDDa, VDDac, and VDDav pins, plus a 100 nF capacitor on VBG, as specified in Section 5 of the datasheet. These are mandatory for stable internal regulation, reference buffering, and noise suppression. No external crystal or oscillator is needed since it accepts an external clock on CLK.

How does the chopper-stabilized amplifier improve measurement accuracy?

The chopper-stabilized PGLNA reduces 1/f noise and input offset voltage drift over temperature and time. As confirmed in Table 5, it achieves ±20 mV offset and maintains <0.04 LSB/uV gain error-critical for maintaining Class 0.2 accuracy in shunt-based current measurement where offset directly contributes to zero-current error.

Can STPMS2L-PUR interface directly with an STM32 microcontroller?

Yes-STPMS2L-PUR outputs differential ΣΔ bitstreams (DAT/DATn) compatible with STM32's DFSDM (Digital Filter for Sigma-Delta Modulators) peripheral. The 40 ns latency and 4.19 MHz clock alignment are supported by STM32H7 and G4 series. No level-shifting is required as both operate at 3.3 V logic levels, and MS0–MS3 can be tied to fixed logic for hard-mode operation.