STMicroelectronics L6370L

Overview

L6370L from STMicroelectronics is a 2.5A high-side intelligent power switch in MULTIWATT11 package, designed for industrial load control with integrated current limiting, thermal shutdown, open-load detection, and dual diagnostic outputs. It drives inductive or resistive loads in PLC output modules, motor starters, and valve actuators, operating from 9.5V to 35V supply with internal clamping diode for fast demagnetization.

For engineers reviewing the L6370L datasheet, L6370L pinout, L6370L application, or L6370L equivalent, this device supports robust industrial switching with programmable short-circuit timing, differential input hysteresis, undervoltage lockout with hysteresis, and IEC 61000-4-4/4-5 transient immunity-critical for factory automation and harsh-environment control systems.

Technical Context

The L6370L integrates a high-side DMOS power switch with non-dissipative short-circuit protection that limits output current to 3.2A (typ.) and sustains it for a programmable ON-delay interval (1.28 µs/pF) before disabling output. Its differential input stage features ±43V common-mode range, 1.4V internal offset, and 400mV hysteresis for noise-immune signal acquisition in noisy industrial environments.

Diagnostic logic continuously monitors output status, supply voltage, junction temperature, and load condition, reporting via two open-drain outputs (DIAG1/DIAG2) using a defined truth table. Internal voltage clamping (VS–VO ≤ 58V) enables safe inductive load demagnetization without external components, while open-load detection triggers at <3mA output current.

Key Specifications

Pinout & Package

MULTIWATT11 (in-line) package: 11-pin vertical through-hole with exposed metal tab for thermal dissipation; pin 9 and 11 are paralleled high-side output terminals; pin 10 is VS supply input; GND on pins 6 and 7; diagnostic and status outputs on dedicated pins.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-side intelligent power switch applications.

Compared with VND5E025AKTR-E and TPS27081A, the L6370L provides superior industrial robustness via integrated clamp, dual diagnostics, and IEC-compliant transient immunity-making it uniquely suitable for unattended factory-floor equipment where reliability and fault visibility are mandatory.

Availability

L6370L is available at Aetrix Electronics and suitable for PLC output modules, industrial valve actuators, motor starter circuits, and factory lighting control systems requiring stable component supply across multi-year production cycles.

Supply support for L6370L 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 power management, microcontrollers, and industrial analog devices with over 40 years of automotive and industrial qualification experience.

The L6370L belongs to ST's Intelligent Power Switch (IPS) product line, engineered specifically for high-reliability industrial control applications demanding integrated protection, diagnostics, and ruggedized operation in harsh electromagnetic environments.

FAQ

What is the maximum inductive energy the L6370L can safely absorb during demagnetization?

The L6370L can absorb up to 1J of inductive energy at junction temperature 85°C, enabled by its internal voltage clamp (VS–VO ≤ 58V). This value is measured under single-pulse conditions with t_p = 300µs and is validated per ST's characterization data in Section 2.3 of the datasheet. External snubbers are unnecessary for solenoids and small relays meeting this energy limit.

How does the ON-DELAY pin affect short-circuit behavior?

The ON-DELAY pin sets the duration (t_ON) that the L6370L sustains short-circuit current before disabling the output. With a capacitor C_ON between ON-DELAY and GND, t_ON = 1.28 µs/pF (e.g., 1nF → 1.28ms). If grounded, non-dissipative protection is disabled and thermal shutdown becomes the sole short-circuit response mechanism.

Can the L6370L drive loads requiring >2.5A peak current?

No-the L6370L's absolute maximum continuous output current is 2.5A, and its short-circuit current limit is 3.2A typical. Exceeding 2.5A continuously violates thermal limits in the MULTIWATT11 package (R_thJA = 35°C/W). For higher currents, ST recommends the L6370D in PowerSO-20 (R_thJA = 25°C/W) or parallel-output configurations with external current sharing.

What diagnostic conditions cause both DIAG1 and DIAG2 to go low simultaneously?

Both DIAG1 and DIAG2 go low only during supply undervoltage (VS < V_sth2 ≈ 8.5V) or overtemperature (T_J > 150°C), as confirmed in Table 7 (Diagnostic Truth Table). In all other fault conditions-including short-to-ground, short-to-VS, and open load-exactly one diagnostic pin asserts low while the other remains high.