STMicroelectronics L9337MD/TR

Overview

L9337MD from STMicroelectronics is a monolithic triple low-side DMOS driver in SO20 (12+4+4) package, designed for automotive and industrial inductive load control. It features 1.5 Ω R_DS(on) at 25°C, programmable inverting/non-inverting signal polarity, reverse bias protection down to −24 V, and integrated diagnostic open-drain output for overtemperature and supply/ground fault detection.

For engineers reviewing the L9337MD datasheet, L9337MD pinout, L9337MD application, or L9337MD equivalent, key selection considerations include its wide −24 V to +45 V input tolerance, <2 µA standby current, controlled 2.5–16 V/µs output slew rate for EMI reduction, and per-channel thermal shutdown with hysteresis.

Technical Context

The L9337MD integrates three independent low-side power DMOS switches with current limiting (~400–1200 mA), active flyback clamping (V_CLAMP ≈ 50 V), and per-channel thermal shutdown (T_OFF = 160–190 °C, T_ON = 140–170 °C). Its Schmitt-trigger inputs provide 100 mV hysteresis and −24 V to +10 V input voltage protection.

Signal polarity is selected via PRG pin: low = non-inverting, high = inverting. The DIAG output reflects system health-low during normal operation (PRG = low), high on overtemperature, supply loss, or ground disconnect-and supports selective per-channel fault reporting.

Key Specifications

Pinout & Package

Package: SO20 (12+4+4), surface-mount, 0.65 mm pitch, thermal resistance R_th(j-pins) = 14 °C/W (typ.), R_th(j-amb) = 77–97 °C/W on SMPCB2 board.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar triple low-side driver applications.

Compared with TPIC2060DWR and BD7682FJ-E2, the L9337MD uniquely combines triple-channel integration, −24 V reverse-bias resilience, programmable polarity, and single-pin diagnostic reporting-making it optimal for space-constrained, fault-aware automotive body electronics.

Availability

L9337MD is available at Aetrix Electronics and suitable for automotive body control modules, industrial PLC output stages, truck lighting systems, and appliance motor drivers requiring stable component supply across extended temperature and voltage ranges.

Supply support for L9337MD 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 vertical manufacturing and broad automotive qualification coverage.

The L9337MD belongs to ST's Automotive Power Drivers product line, engineered specifically for robust, diagnostic-capable control of inductive and resistive loads in harsh 12 V/24 V vehicle environments.

FAQ

What is the maximum safe operating voltage on the VS pin?

The absolute maximum rating for VS is −24 V to +45 V with no damage or latch-up. For reliable long-term operation, the recommended supply range is 4.5 V to 32 V. Operation at −24 V is validated for reverse-battery conditions per ISO 16750-2, and the device remains functional with full diagnostic reporting during this state.

How does the DIAG pin behave when PRG is tied to VS?

When PRG = high (tied to VS), the DIAG output is actively disabled during normal operation (open-drain high-impedance) and pulls low only during overtemperature events. This inverted logic allows direct connection to an MCU interrupt pin without external inversion, simplifying fault-handling firmware for thermal overload detection.

Can L9337MD drive inductive loads without external flyback diodes?

Yes-the L9337MD integrates active flyback clamping that limits output voltage to 45–60 V during inductive recirculation. This eliminates the need for external freewheeling diodes in most 12 V/24 V solenoid and relay applications, provided load energy stays within the clamp's 100 ns–200 µs pulse capability and peak current remains below 1.2 A.

What happens if an input pin (IN1–IN3) is left floating?

All input pins have internal pull-down circuitry. An open INx pin defaults to logic low, forcing the corresponding output to OFF state-ensuring fail-safe behavior during MCU initialization, reset, or wiring faults. This eliminates risk of unintended load activation and complies with ASIL-B functional safety expectations for automotive use.