STPM12ATR

Overview

The STPM12ATR is a single-phase energy metering integrated circuit designed for active energy measurement in power line systems. It supports shunt, current transformer, and Rogowski coil sensors. The device features a first-order sigma-delta A/D converter and an internal hard-wired DSP for computing consumed energy. It provides a ripple-free pulsed output proportional to energy, driven by a direct stepper counter. Key electrical parameters include a supply voltage range of 3V to 5.5V, a maximum supply current of 4.7mA, and an input impedance of 100kΩ. The measurement error is specified at less than 0.1%. It operates within a temperature range of -40°C to 85°C and is housed in a 20-TSSOP package.

Feature Summary

• Integrates analog preamplifier, sigma-delta A/D converter, and digital signal processor for standalone single-phase metering without additional active components.
• Generates a ripple-free active energy pulsed output directly compatible with stepper counters for easy calibration and monitoring.
• Supports digital calibration via one-time programmable (OTP) cells through a serial interface, allowing configuration locking to prevent unauthorized changes.
• Includes built-in indicators for no-load conditions, negative power flow, and tamper detection.

Applications

• Single-phase residential and commercial energy meters
• Smart metering systems utilizing shunt or current transformer sensors
• Energy monitoring devices requiring high-precision active energy measurement

Procurement Notes

Verify the obsolete status of this component before design finalization. Confirm that the 20-TSSOP package dimensions align with your PCB footprint. Ensure the 3V to 5.5V supply voltage range matches your system's power architecture. Check if the crystal oscillator requirement for the STPM12 variant fits your timing constraints. Validate that the single-phase specification meets your application needs.

Selection Notes

Select this component for applications requiring high accuracy with less than 0.1% error in single-phase energy measurement. It is suitable for designs aiming to minimize external component count by integrating DSP and calibration logic. Consider the 20-TSSOP package size for space-constrained boards. Ensure compatibility with shunt, CT, or Rogowski coil inputs. Verify that the operating temperature range of -40°C to 85°C covers your environmental requirements.

Part Context

The STPM12ATR belongs to the STPM1x family of single-phase energy metering ICs from STMicroelectronics. This family is engineered to provide complete metering solutions using various sensor types. The STPM12 specifically utilizes a crystal oscillator for timing, distinguishing it from variants like the STPM11 which use RC oscillators. The 'ATR' suffix typically denotes the tape-and-reel packaging format for surface-mount assembly.

FAQ

What type of oscillator does the STPM12ATR use?

The STPM12ATR uses a crystal oscillator for its timing reference, as opposed to the RC oscillator found in other members of the STPM1x family like the STPM11.

How is the calibration data stored in the STPM12ATR?

Calibration and configuration data are stored in One-Time Programmable (OTP) cells, which can be programmed via a serial interface and locked to prevent accidental modification.