STMicroelectronics L6235Q

Overview

L6235Q from STMicroelectronics is a fully integrated DMOS 3-phase brushless DC motor driver with Hall-effect decoding logic, constant t_OFF PWM current control, and non-dissipative overcurrent protection. It delivers 5.6 A peak output current, operates from 8–52 V supply, features R_DS(on) = 0.34 Ω (typ.) at 25 °C for high-side switches, and supports 100 kHz switching frequency - used in closed-loop BLDC motor control systems for industrial actuators and HVAC blowers.

For engineers reviewing the L6235Q datasheet, L6235Q pinout, L6235Q application, or L6235Q equivalent, key selection considerations include its integrated slow-decay synchronous rectification, 60°/120° Hall sensor decoding flexibility, tacho output for speed feedback, brake function, and QFN48 (7 × 7 mm) thermal-performance-optimized package.

Technical Context

The L6235Q integrates six DMOS power transistors in a 3-phase bridge with intrinsic fast freewheeling diodes, driven by CMOS/bipolar logic on BCD-multipower technology. Its Hall decoding logic accepts three single-ended inputs (H1–H3) and autonomously selects between 60° and 120° electrical phasing without external configuration pins.

Current regulation uses a constant t_OFF PWM controller with blanking time (1 µs), adjustable OFF time via external R_COFF/C_COFF, and internal dead time (1 µs typ.) to prevent cross-conduction. Overcurrent detection is non-dissipative and tied to high-side MOSFETs, with diagnostic reporting via open-drain DIAG pin.

Key Specifications

Pinout & Package

Package: QFN48 (7 × 7 mm), exposed thermal pad requiring GND connection per datasheet Figure 2.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 3-phase BLDC motor driver applications.

Compared with DRV8313 and STSPIN32F0A, the L6235Q uniquely delivers autonomous Hall decoding, non-dissipative OCD, and slow-decay rectification in a pure analog/digital hybrid IC - offering fastest time-to-operation for Hall-based BLDC systems without firmware development or SPI configuration overhead.

Availability

L6235Q is available at Aetrix Electronics and suitable for industrial fan control, HVAC blower systems, and automotive coolant pump designs requiring stable component supply, long-term lifecycle assurance, and full traceability from wafer lot to shipment.

Supply support for L6235Q 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 silicon solutions for automotive, industrial, and power applications since 1987.

The L6235Q belongs to ST's high-voltage motor driver product line, engineered specifically for robust, integrated 3-phase BLDC control in space-constrained, thermally demanding environments - emphasizing reliability, protection integrity, and ease of analog implementation.

FAQ

What is the minimum required external component set to operate the L6235Q?

The essential external components are: (1) a single current-sense resistor between SENSEA/SENSEB and GND; (2) bootstrap capacitors (220 nF) and diodes (1N4148) per half-bridge; (3) R_COFF/C_COFF network (e.g., 20 kΩ/1 nF) for t_OFF setting; and (4) pull-up resistors on H1–H3 if open-collector Hall sensors are used. No external gate resistors or level shifters are needed.

How does the L6235Q handle reverse recovery spikes during PWM switching?

The L6235Q incorporates a 1 µs internal blanking time on the sense comparator that disables overcurrent detection immediately after power MOSFET turn-on. This prevents false triggering from the reverse recovery current spike of the intrinsic freewheeling diodes, ensuring stable current regulation even with fast-switching, low-inductance motors.

Can the L6235Q drive motors with Hall sensors spaced at 240° or 300° electrical angles?

Yes - the decoding logic recognizes 240° and 300° phasing as reversed sequences of 120° and 60° configurations respectively. By asserting the FWD/REV pin appropriately, the device automatically maps these reversed codes to correct commutation states without additional hardware or firmware changes.

What thermal derating applies when operating above 100 °C junction temperature?

Per Table 4, R_DS(on) increases to 0.59 Ω (max) at T_j = 125 °C, raising conduction loss by ~75% versus 25 °C. The thermal shutdown threshold is fixed at 165 °C, and operation above 125 °C is not recommended - PCB layout must ensure ≤1.8 °C/W junction-to-board thermal resistance to sustain 5.6 A peak at ambient 85 °C.