STMicroelectronics AEK-POW-BMSWTX

Overview

AEK-POW-BMSWTX from STMicroelectronics is an automotive-grade battery management system (BMS) evaluation board supporting 4–14 Li-ion cells, built around the AEC-Q100 qualified L9963E cell monitor and L9963T isolated SPI transceiver. It delivers per-cell voltage monitoring (±1.5 mV accuracy), pack current sensing, passive balancing via internal MOSFETs, and 5 GPIOs for NTC temperature sensors - enabling SOC/SOH estimation and safe operation in e-mobility applications.

For engineers reviewing the AEK-POW-BMSWTX datasheet, AEK-POW-BMSWTX pinout, AEK-POW-BMSWTX application, or AEK-POW-BMSWTX equivalent, this board provides verified isolated SPI communication, daisy-chain scalability up to 31 devices, real-time stack/cell voltage measurement, silent balancing in low-power mode, and AutoDevKit software integration for SOC/SOH algorithm validation.

Technical Context

The board implements a dual-IC architecture: the L9963E performs high-accuracy analog front-end measurements (cell voltage, stack voltage, current via external shunt, temperature via NTCs) and executes coulomb counting, while the L9963T acts as a slave-configured bidirectional isolator converting standard 4-wire SPI to 2-wire isolated SPI (ISOHp/ISOHm). Measurement data is programmable for on-demand or periodic acquisition with user-defined cycle intervals.

All 14 cell inputs are routed to the L9963E's dedicated analog channels; current sensing uses differential ISENSEp/ISENSEm inputs with ±50 mV full-scale range; passive balancing is controlled via internal 120 mΩ MOSFETs driving external dissipation resistors already mounted on-board. The CN1 and CN2 connectors provide standardized MCU interface paths for control, diagnostics, and isolated communication.

Key Specifications

Availability

AEK-POW-BMSWTX is available at Aetrix Electronics and suitable for battery management systems, e-mobility powertrain development, and home energy storage prototyping requiring stable component supply, automotive qualification traceability, and rapid firmware validation cycles.

Supply support for AEK-POW-BMSWTX 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, designing and manufacturing microcontrollers, power ICs, sensors, and automotive-grade analog/mixed-signal solutions used in industrial, automotive, and consumer applications.

The AEK-POW-BMSWTX belongs to ST's AutoDevKit ecosystem - a family of automotive-qualified evaluation platforms designed to accelerate functional safety-compliant BMS development, particularly for ASIL-B/C systems using SPC5 microcontrollers and L9963-series monitoring ICs.

FAQ

Does AEK-POW-BMSWTX support daisy-chaining with other L9963E-based boards?

Yes - the board implements the L9963E's native daisy-chain capability, allowing up to 31 devices in series via dedicated ISOHp/ISOHm isolation links. This enables scalable monitoring of large battery stacks without additional level-shifting or isolation components, and is validated in ST's AutoDevKit software stack.

What MCU families are officially supported for interfacing with AEK-POW-BMSWTX?

The board is natively integrated with ST's SPC5 Chorus 4M automotive microcontrollers (e.g., AEK-MCU-C4MLIT1), supporting ASIL-B and ASIL-D compliance. It also interoperates with any SPI-capable MCU that implements the L9963E register map and timing requirements, including ARM Cortex-M and RH850 derivatives used in production BMS controllers.

Can passive balancing be activated autonomously by the L9963E without MCU intervention?

Yes - the L9963E supports "silent balancing", where balancing continues during low-power modes using internal timers and thresholds. The board's pre-mounted resistors and MOSFETs allow fully autonomous discharge when cell voltage deviation exceeds programmable limits, reducing MCU wake-up frequency and system power consumption.

Is the isolated SPI interface on AEK-POW-BMSWTX configurable as master or slave?

No - the L9963T transceiver on this board is hardwired and configured exclusively as a slave device, receiving commands from the host MCU via CN1. The isolated side (ISOHp/ISOHm) connects only to the L9963E, enforcing a unidirectional control architecture required for functional safety partitioning in automotive BMS designs.