STMicroelectronics STLUX385

Overview

STLUX385 from STMicroelectronics is a digital controller IC for lighting and power supply systems, integrating an enhanced STM8 core (16 MHz max CPU), 6 independent SMED-based PWM generators, 96 MHz PLL, DALI interface, and a gain-programmable 10-bit ADC with op-amp extension to 12-bit effective resolution. It targets LED drivers, fluorescent ballasts, and HID lamp control.

For engineers reviewing the STLUX385 datasheet, STLUX385 pinout, STLUX385 application, or STLUX385 equivalent, key selection considerations include its DALI target device compliance, six programmable PWM channels with event-driven state machines, 50 ns analog comparator propagation delay, and TSSOP38 package compatibility with high-density lighting control PCB layouts.

Technical Context

The STLUX385 implements a Harvard-architecture STM8 core with 3-stage pipeline and 24-bit linear addressing, supporting non-intrusive debugging via SWIM single-wire interface. Its clock system combines internal 16 MHz and 153.6 kHz RC oscillators, external crystal support up to 24 MHz, and a user-configurable 96 MHz PLL for precise PWM timing.

Peripheral integration centers on six SMED units-state-machine event-driven PWM generators-with a programmable connection box enabling complex timer topologies. The DALI hardware cell handles physical layer signaling and protocol framing per IEC 62386-102, while four 4-bit DACs feed internal reference voltages to analog comparators with 50 ns max cycle time.

Key Specifications

Pinout & Package

TSSOP38 package (9.7 mm × 6.4 mm × 1.05 mm height), RoHS-compliant ECOPACK® grade, with exposed pad not present. Pin count: 38 leads, 0.5 mm pitch, dual-row surface-mount.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar digital lighting controller applications.

Compared with STLUX385, the STLUX385A offers verified improvements in ESD tolerance without functional change, while the IRS2540SPBF provides only gate-driving capability-requiring separate MCU, communication IC, and signal conditioning for equivalent system functionality.

Availability

STLUX385 is available at Aetrix Electronics and suitable for LED driver control, fluorescent ballast design, and HID lamp ballast development requiring stable component supply and long-term industrial lifecycle support.

Supply support for STLUX385 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 microcontrollers, power ICs, sensors, and analog products for industrial, automotive, and consumer markets.

The STLUX series targets intelligent lighting control, combining STM8 processing with application-specific peripherals like DALI, SMED PWM, and high-speed analog front-ends to replace discrete analog controllers in solid-state lighting systems.

FAQ

What is the maximum operating frequency of the STLUX385's internal PLL?

The STLUX385 integrates a user-configurable 96 MHz PLL used to derive high-resolution timing for its six SMED PWM generators. This PLL operates independently of the 16 MHz CPU clock and enables sub-nanosecond PWM edge placement precision, critical for resonant converter control and acoustic noise suppression in HID lamps.

Does the STLUX385 require an external DALI transceiver?

No. The STLUX385 includes a fully integrated DALI hardware cell compliant with IEC 62386-102, supporting both physical layer signaling and protocol framing. Pins 14 (DALI_TX) and 15 (DALI_RX) connect directly to the DALI bus through standard current-limiting resistors and transient protection-no external transceiver IC is needed.

How many analog inputs does the STLUX385 ADC support, and what is its effective resolution?

The STLUX385 ADC supports eight analog input channels (ADCIN[0]–ADCIN[7]) with 10-bit SAR conversion. When configured with the internal operational amplifier, selectable gain settings (x1.6 or x6.4) extend the effective resolution to 12 bits, enabling precise current sensing across wide dynamic ranges in LED driver and PFC applications.

What debug interface does the STLUX385 provide, and is it compatible with standard tools?

The STLUX385 uses the SWIM (Single-Wire Interface Module) debug interface, a proprietary ST protocol accessible via ST-LINK/V2 or compatible programmers. It supports non-intrusive real-time debugging, flash programming, and memory inspection without requiring additional pins or JTAG headers-fully supported by STM8CubeIDE and ST's official toolchain.