STMicroelectronics L9338DTR

Overview

L9338DTR from STMicroelectronics is a monolithic quad low-side DMOS driver in SO-20 package, designed for automotive and industrial inductive load control. It features four open-drain outputs with R_DS(on) = 1.7 Ω (typ.) at 25°C, programmable signal polarity (inverting/non-inverting), reverse bias protection to −24 V, and integrated diagnostic output with overtemperature and supply/ground disconnect monitoring.

For engineers reviewing the L9338DTR datasheet, L9338DTR pinout, L9338DTR application, or L9338DTR equivalent, key selection criteria include wide input voltage range (−24 V to +45 V), <2 µA standby quiescent current, controlled output slew rate (2.5–16 V/µs), thermal shutdown per channel, and TTL/CMOS-compatible Schmitt-trigger inputs with 100 mV hysteresis.

Technical Context

The L9338DTR implements four independent low-side power switches using Multipower-BCD technology, each with current limiting (400–1200 mA), fast active flyback clamping (V_CLAMP = 45–60 V), and thermal shutdown triggered at 160–190°C junction temperature. Its diagnostic output provides channel-selective fault reporting based on PRG pin state.

Input logic supports both inverting and non-inverting transfer modes via the PRG pin; EN enables global sleep mode (<2 µA I_Q); all inputs tolerate −24 V to +45 V and feature internal ESD protection (2 kV HBM). Outputs are open-drain with internal pull-down for defined OFF-state during open-input conditions.

Key Specifications

Pinout & Package

Package: SO-20 (Small Outline, 20-pin, 0.65 mm pitch), body dimensions 12.8 × 7.5 mm, thermal resistance R_th(j-pins) = 14 °C/W (typ.), suitable for surface-mount reflow assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPIC2810PW and BD8960AEFJ-ME2, the L9338DTR uniquely combines reverse-battery resilience, per-channel thermal shutdown, and programmable logic polarity - making it the only option qualified for ASIL-B-relevant automotive body electronics without external protection.

Availability

L9338DTR is available at Aetrix Electronics and suitable for automotive body control modules, industrial PLC output stages, truck trailer lighting interfaces, and off-highway equipment harness management requiring stable component supply across extended temperature and voltage ranges.

Supply support for L9338DTR 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 AEC-Q100 qualification expertise.

The L9338DTR belongs to ST's Automotive Power Switch family, engineered specifically for robust, diagnostic-capable low-side driving of inductive and resistive loads in harsh environments - including engine bays, chassis modules, and heavy-equipment control units.

FAQ

What is the maximum allowable negative supply voltage for L9338DTR?

The L9338DTR supports VS down to −24 V under absolute maximum ratings, with full functionality preserved across its operating range of 4.5 V to 32 V. This reverse-bias capability enables direct connection to automotive battery lines without external protection diodes, even during jump-start or reverse-connection events.

How does the DIAG output behave during thermal shutdown?

When any output channel exceeds its thermal shutdown threshold (160–190°C), the DIAG pin goes high if PRG = low, or low if PRG = high - providing polarity-selectable fault signaling. The diagnostic response is channel-selective and remains asserted until junction temperature falls ~20°C below trip level, ensuring reliable latch-free recovery.

Can L9338DTR drive inductive loads without external flyback diodes?

Yes. The L9338DTR integrates active flyback clamping that limits output voltage to 45–60 V during inductive recirculation, with response time <200 µs. This eliminates the need for external freewheeling diodes when driving solenoids, relays, or valves within its current and energy limits.

Is the PRG pin required to be actively driven, or can it be left floating?

The PRG pin has an internal weak pull-down; an open (floating) PRG defaults to logic low, selecting non-inverting signal transfer polarity. For inverting mode, PRG must be actively pulled high to VS. Leaving it unconnected is functionally valid and commonly used in non-inverting applications.