STMicroelectronics ST7538P013TR

Overview

ST7538P013TR from STMicroelectronics is a half-duplex FSK power line transceiver IC integrating a programmable line driver, 5V linear regulator (100mA), carrier/preamble detection, zero-crossing synchronization, and watchdog timer. It operates from 7.5–12.5V single supply, consumes only 5mA quiescent current, supports 8 carrier frequencies (60–132.5kHz), and delivers up to 4800bps baud rate - deployed in EN 50065-compliant smart metering and home automation PLC networks.

For engineers reviewing the ST7538P013TR datasheet, ST7538P013TR pinout, ST7538P013TR application, or ST7538P013TR equivalent, key selection considerations include its integrated analog front-end for mains-coupled signaling, synchronous/asynchronous serial interface configuration, voltage/current-controlled PLI output compliance with CENELEC A-band limits, and register-based security checksum for firmware integrity.

Technical Context

The ST7538P013TR implements a fully integrated FSK modem architecture with dual-path analog signal chain: one path for high-sensitivity reception (250µV_RMS) via RAI input and bandpass filtering, another for programmable transmission using DAC-driven ATO and DMOS-based ATOP1/ATOP2 outputs. Its internal PLL recovers clock during synchronous RX, while asynchronous mode relies on host timing recovery.

Control is managed through a 24-bit programmable register accessed via synchronous serial interface (CLR/T, RxD, TxD, REG_DATA, RxTx), enabling dynamic configuration of carrier frequency, baud rate, ALC gain steps (0.6–1.4dB), voltage/current control thresholds (VCLTH = 160–200mV_PK, CCLTH = 1.80–2.00V), and zero-crossing detection hysteresis (±18mV).

Key Specifications

Pinout & Package

TQFP44 (slug-down) package with exposed thermal pad for enhanced power dissipation in continuous TX operation; pin 6 and pin 41 are substrate ground (GND) tied internally to AVss/DVss reference plane.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar FSK power line transceiver applications.

Compared with TLK10031 and MAX2990, the ST7538P013TR uniquely combines CENELEC A-band FSK modulation, zero-crossing synchronization, integrated 5V regulator, and hardware-level EN 50065 compliance functions - making it the sole option for cost-sensitive, standards-constrained smart meter upgrades.

Availability

ST7538P013TR is available at Aetrix Electronics and suitable for smart metering, home automation PLC hubs, streetlight remote management, and industrial building energy monitoring requiring stable component supply and long-term lifecycle support.

Supply support for ST7538P013TR 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 specializing in automotive, industrial, and power management ICs, with broad expertise in mixed-signal and high-voltage process technologies.

The ST7538 belongs to ST's legacy power line communication (PLC) transceiver product line, designed specifically for EN 50065-compliant narrowband FSK communication over AC mains in utility and building automation applications.

FAQ

What is the maximum allowed PAVcc slew rate during power-up?

The ST7538P013TR specifies a maximum power-up slope of 100 V/ms for PAVcc to prevent latch-up or internal regulator instability. Exceeding this rate may cause undefined behavior in the voltage control loop or premature activation of the power-good flag. This requirement is verified in Table 4 Absolute Maximum Ratings and applies regardless of DVcc/AVdd sequencing.

How does the band-in-use (BU) detection function operate?

The BU pin asserts high when signal energy within the currently programmed carrier band exceeds –85 dB/µVrms (typical), determined by internal RSSI measurement and digital threshold comparison. It is independent of carrier detection and remains active during both TX and RX modes, enabling real-time spectrum occupancy awareness for channel selection algorithms.

Can the ST7538P013TR drive a 50Ω load directly?

No - the ATOP1/ATOP2 outputs are optimized for high-impedance coupling to AC mains (typically >1kΩ via series capacitor). Driving 50Ω would exceed the specified 370mArms maximum current and risk thermal shutdown. For low-Z loads, an external step-up transformer or buffer amplifier is required per Figure 17 in the datasheet.

What happens if the REGOK pin goes high during normal operation?

A high REGOK signal indicates corruption of the 24-bit control register contents, typically caused by ESD event or voltage glitch on DVcc. The device continues operating with last-valid register values but disables new register writes until a full power cycle or watchdog reset clears the error state. No automatic recovery occurs in firmware.