STMicroelectronics L9958XPTR

Overview

L9958XPTR from STMicroelectronics is a SPI-controlled dual-channel H-bridge motor driver IC designed for safety-critical DC and stepper motor control in automotive and industrial environments. It delivers programmable current regulation up to 8.6 A (typ.), operates from 4.0 V to 28 V battery supply, features full-path R_ON from 100 mΩ (–40 °C) to 300 mΩ (150 °C), and integrates overtemperature, short-circuit, and open-load diagnostics for robust system protection.

For engineers reviewing the L9958XPTR datasheet, L9958XPTR pinout, L9958XPTR application, or L9958XPTR equivalent, key selection considerations include its PowerSSO24 package compatibility, 16-bit SPI daisy-chain capability, voltage/current slew-rate control for EMI reduction, and diagnostic register access for real-time fault reporting in ON/OFF states.

Technical Context

The L9958XPTR implements a fully integrated H-bridge with internal freewheeling diodes and active low-side MOSFET switching during freewheeling to reduce power dissipation. Its control logic accepts TTL/CMOS-compatible DIR, PWM, EN, and DI inputs, with independent tristate control via EN (pull-down) and DI (pull-up) pins.

SPI communication enables configuration of current limit threshold (2.5–8.6 A in 4 steps), slew rate, and diagnostic reporting; all faults force outputs to tristate and set corresponding bits in the DIA_REG register. Thermal warning activates at >165 °C, with automatic current limit reduction above that threshold.

Key Specifications

Pinout & Package

The L9958XPTR is packaged in PowerSSO24 (JEDEC MO271A), a low-cost, thermally enhanced 24-pin exposed-slug package requiring local PCB grounding of both PGND (pin 11) and GND (pin 22). The slug must be soldered and connected to system ground for thermal and electrical integrity.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar H-bridge motor driver applications.

Compared with STSPIN840 and VNH7040AS, the L9958XPTR uniquely combines dual-channel H-bridge topology, programmable 8.6 A current regulation, comprehensive SPI-accessible diagnostics, and PowerSSO24 thermal performance-making it the only option qualified for ASIL-B–aligned safety-critical motor control.

Availability

L9958XPTR is available at Aetrix Electronics and suitable for automotive HVAC systems, industrial linear actuators, medical infusion pumps, and off-highway steering assist modules requiring stable component supply across extended temperature and voltage ranges.

Supply support for L9958XPTR 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 emphasis on functional safety and reliability.

The L9958XPTR belongs to ST's L99 family of automotive-grade motor drivers, engineered specifically for safety-critical applications demanding ASIL-B compliance, extended environmental resilience, and deep diagnostic visibility.

FAQ

What is the maximum continuous output current supported by L9958XPTR?

The L9958XPTR does not specify a fixed maximum continuous current; instead, it offers programmable peak current regulation from 2.5 A to 8.6 A (typ.) via external R_EXT. Continuous current capability depends on PCB thermal design, ambient temperature, and duty cycle - with full-path R_ON ranging from 100 mΩ (–40 °C) to 300 mΩ (150 °C) defining conduction loss limits.

Does L9958XPTR support daisy-chained SPI configuration?

Yes, the L9958XPTR supports true daisy-chain SPI operation with no hardware address lines required. Multiple devices share SI, SCK, and CS signals; SO of one device connects to SI of the next. Each device shifts out its 16-bit response in sequence, enabling centralized diagnostics and configuration of up to dozens of drivers using a single MCU SPI port.

How does open-load detection work in ON state versus OFF state?

In ON state, open-load detection uses low-side current recirculation monitoring during freewheeling phases to identify missing motor connection. In OFF state, it applies a small test current through the bridge and measures voltage drop across OUT1/OUT2 to detect open circuits - allowing fault verification before motor activation, which is essential for safety pre-check sequences.

Can L9958XPTR operate with a 3.3 V microcontroller SPI interface?

Yes - the L9958XPTR includes a dedicated VDDIO pin (pin 4 in PowerSSO24) that accepts 3.3 V or 5 V, making its SPI interface fully compatible with both 3.3 V and 5 V microcontrollers. Logic inputs (DIR, PWM, EN, DI) are also TTL/CMOS-compatible and tolerate either voltage level without level-shifting circuitry.