Analog Devices, Inc., which recently acquired Linear Technology Corporation, announces the LT8606, a 350 mA, 42 V input synchronous step-down switching regulator. A unique synchronous rectification topology delivers 92 percent efficiency while switching at 2 MHz, enabling designers to avoid critical noise-sensitive frequency bands, such as AM radio while using a very compact solution footprint.

Burst Mode® operation keeps quiescent current under 3 µA in no-load standby conditions, ideal for always-on systems. Its 3 to 42 V input voltage range makes it suitable for automotive applications which must regulate through cold-crank and stop-start scenarios with minimum input voltage as low as 3 V and load dump transients in excess of 40 V. Its internal 650 mA switches deliver up to 350 mA of continuous output current. The LT8606 maintains a minimum dropout voltage of only 175 mV (at 300 mA) under all conditions, enabling it to excel in scenarios such as automotive cold-crank. Spread spectrum frequency modulation and special design techniques offer low EMI operation, enabling it to meet CISPR25, Class 5 EMI limits required by many automotive and industrial applications. Furthermore, a fast minimum on-time of only 45 ns enables 2 MHz constant frequency switching from a 16 V input to a 1.5 V output. The LT8606’s 2 mm x 2 mm 8-lead DFN or 10-lead thermally enhanced MSOP package and high switching frequency, which keeps the external inductor and capacitors small, provide a compact, thermally efficient footprint.

The LT8606 utilizes internal top and bottom high efficiency power switches with the necessary boost diode, oscillator, control and logic circuitry integrated into a single die. Low ripple Burst Mode operation maintains high efficiency at low output currents while keeping output ripple below 10 mVP-P. Unique design techniques and a high speed process enable high efficiency over a wide input voltage range, and the LT8606’s current mode topology enables fast transient response and excellent loop stability. Other features include internal compensation, a power good flag, output soft-start/tracking and thermal protection. 

The LT8606EDC is packaged in a 2 mm x 2 mm 8-lead DFN package and the LT8606EMSE is offered in a thermally enhanced MSOP-10 package. Industrial temperature versions, the LT8606IDC and LT8606IMSE, are tested and guaranteed to operate from a –40°C to 125°C operating junction temperature. Pricing starts at $2.05 each in 1000-piece quantities and both versions are available from stock. For more information, visit

Summary of Features: LT8606

  • Wide Input Voltage Range: 3 to 42 V
  • Ultralow Quiescent Current Burst Mode® Operation:
    • < 3 µA IQ Regulating 12 VIN to 3.3 VOUT
    • Output Ripple <10mVP-P
  • High Efficiency 2 MHz Synchronous Operation:
    • > 92 percent Efficiency at 0.35 A, 12 VIN to 5 VOUT
  • 350 mA Maximum Continuous Output
  • Fast Minimum Switch-On Time: 45 ns
  • Adjustable & Synchronizable: 200 kHz to 2.2 MHz
  • Spread Spectrum Frequency Modulation for Low EMI
  • Allows Use of Small Inductors
  • Low Dropout
  • Peak Current Mode Operation
  • Accurate 1 V Enable Pin Threshold
  • Internal Compensation
  • Output Soft-Start & Tracking
  • Tiny 2 mm x 2 mm 8-Lead DFN or 10-Lead MSOP Package