IS32LT3957A-ZLA3

Overview

The IS32LT3957A-ZLA3 is a high-voltage LED lighting controller from Lumissil Microsystems, designed for automotive and general lighting applications. It operates as a DC-DC controller supporting SEPIC, Buck, and Boost topologies with a switching frequency range of 100kHz to 1MHz. The device accepts an input voltage between 5V and 75V and features PWM dimming capabilities. Packaged in a 16-pin eTSSOP (4.40mm wide) with exposed pad, it functions within a temperature range of -40°C to 125°C and holds AEC-Q100 automotive grade certification.

Feature Summary

• Supports multiple power converter topologies including SEPIC, Buck, and Boost for flexible LED drive configurations.
• Integrates fault protection mechanisms to ensure extended-life operation and system reliability.
• Provides analog dimming capability down to 10% for precise brightness control.
• Includes spread spectrum technology to mitigate electromagnetic interference.

Applications

• Automotive exterior lighting systems
• Commercial general lighting fixtures
• Residential LED lighting solutions

Procurement Notes

Verify the specific suffix ZLA3 corresponds to the required tape and reel packaging quantity of 2500 units. Confirm that the eTSSOP-16 package dimensions match the PCB footprint requirements. Ensure the design accounts for the 75V maximum input voltage rating. Check for RoHS3 compliance documentation if required by regional regulations. Validate thermal performance under the specified operating temperature range.

Selection Notes

Select this component when a single-channel controller must support varying LED string voltages via SEPIC or Buck-Boost architectures. It is suitable for designs requiring integrated fault protection and analog dimming without external MOSFETs if monolithic options are preferred, though this part typically drives external switches. Consider the 16-pin eTSSOP package for space-constrained boards. Verify compatibility with the target switching frequency range for EMI filtering requirements.

Part Context

This part belongs to the IS32LT3957 family of high-voltage LED drivers from Lumissil Microsystems. The family addresses general lighting markets with monolithic and controller-based solutions. Similar parts in the portfolio include the IS32LT3962, which offers dual-channel outputs. The series emphasizes built-in protections and flexibility for commercial and automotive applications.

Replacement Considerations

Direct substitutes require matching the 16-eTSSOP package and 75V input range. Evaluate alternatives based on topology support (SEPIC/Buck/Boost). Verify equivalent thermal ratings (-40°C to 125°C) and automotive qualification status. Cross-reference pinouts to ensure compatibility with existing PCB layouts.

FAQ

What power converter topologies does the IS32LT3957A support?

It supports SEPIC, Step-Down (Buck), and Step-Up (Boost) topologies.

Is the IS32LT3957A certified for automotive use?

Yes, it is rated as an automotive-grade component.

What is the minimum input voltage for operation?

The minimum supply voltage is 5V.