Texas Instruments LM686x5-Q1 Buck DC/DC Converters

Texas Instruments LM686x5-Q1 Buck DC/DC Converters are designed for high efficiency, high-power density, and ultra-low electromagnetic interference (EMI). These DC/DC converters operate with an input voltage range of 3V to 65V and a temperature range of -40°C to 125°C. temperature range. The LM686x5-Q1 converters are automotive devices with Low-EMI ZEN 1 Switcher Technology Optimized for safety-relevant applications. The LM686x5-Q1 devices are available with pin-selectable fixed output voltages of 3.3V and 5V, or in an adjustable configuration. These LM686x5-Q1 devices are AEC-Q100 qualified for automotive applications. The LM686x5-Q1 converters are offered in a 3.6mm x 2.6mm, thermally enhanced, 20-pin eQFN package. These devices are suitable for Advanced Driver Assistance Systems (ADAS), automotive infotainment and cluster, hybrid, electric, and powertrain systems.

Features

  • AEC-Q100 qualified for automotive applications:
  • -40°C to 125°C, TA temperature grade 1
  • Functional safety-compliant:
    • Documentation available to aid ISO 26262 system designs planned
    • Systematic capability up to ASIL D
    • Hardware capability up to ASIL C
    • Analog built-in self-test at start-up
    • Redundant and fast (0.35μs) VOUT monitor
    • Feedback path failure detection
    • Redundant temperature sensor
    • Excellent pin FMEA and pin spacing
  • 3V to 65V wide input voltage range and meets LV148 / ISO21780 requirements
  • ZEN 1 switcher technology:
    • Facilitates CISPR 25 class 5 compliance
    • ±5% dual-random spread spectrum
    • Enhanced HotRod™ QFN package
    • 300kHz to 2.2MHz switching frequency range
    • Pin-configurable AUTO or FPWM operation
    • Internal compensation, current limit, and Thermal Shutdown (TSD)
  • 40ns (maximum) with low minimum on time: 
    • Enables 36VIN to 3.3VOUT at 2.2MHz
  • High-efficiency power conversion at all loads:
    • >94% peak efficiency at 24VIN, 5VOUT, 400kHz
    • 2.5µA switching input current at no load
  • High power density:
    • Compact 3.6mm x 2.6mm, 20-pin eQFN package with wettable flank
    • Pin compatible with 36V 4/6/8A LM654x0-Q1
    • ϴJA = 24.0°C/W (LM65645-Q1EVM)
  • Create a custom design using the LM686x5-Q1 with the WEBENCH® Power Designer

Applications

  • Advanced Driver Assistance Systems (ADAS)
  • Automotive infotainment and cluster
  • Hybrid, electric, and powertrain systems

Schematic

Schematic - Texas Instruments LM686x5-Q1 Buck DC/DC Converters
Published: 2025-12-31 | Updated: 2026-01-16