65V, 2.2MHz Synchronous Step-Down Switcher

Summary of Features -Wide Input Voltage Range: 3.4V to 65V -Ultralow Quiescent Current Burst Mode® Operation: -2.5μA IQ Regulating 12VIN to 3.3VOUT, Output Ripple < 10mVPK-PK -High Efficiency Synchronous Operation: -94% Efficiency at 1A, 12VIN to 5VOUT -92% Efficiency at 1A, 12VIN to 3.3VOUT -Fast 30ns Minimum Switch-On Time -Low Dropout under All Conditions: 250mV at 1A -Safely Tolerates Inductor Saturation in Overload -Low EMI -Adjustable & Synchronizable: 200kHz to 2.2MHz -Accurate 1V Enable Pin Threshold -Internal Compensation -Output Soft-Start &Tracking -Small Thermally Enhanced 16-Lead MSOP & 3mm × 5mm 24-Lead QFN Packages

Its 3.4V to 65V input voltage range makes it ideal for automotive (single and dual battery) and industrial applications. Its internal high efficiency switches can deliver up to 2A of continuous output current to voltages as low as 0.97V. The LT8620’s Burst Mode operation offers ultralow quiescent current, making it well suited for applications such as automotive “always-on” systems, which need to extend operating battery life. The LT8620’s unique design maintains a minimum dropout voltage of only 250mV at 1A under all conditions, enabling it to excel in scenarios such as automotive cold-crank. The device’s fast minimum on-time of only 30ns enables 2MHz constant frequency switching from a 16V input to a 1.5V output, enabling designers to optimize efficiency while avoiding critical noise-sensitive frequency bands. The LT8620’s 24-lead 3mm x 5mm QFN or thermally enhanced MSOP-16E package and a high switching frequency keeps external inductors and capacitors small, providing a compact, thermally efficient footprint. The LT8620 integrates 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 10mVPK-PK. Special design techniques and a new high speed process enable high efficiency over a wide input voltage range, and the LT8620’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 LT8620EUDD is packaged in a 24-lead, 3mm x 5mm QFN package and the LT8620EMSE is packaged in a thermally enhanced MSOP-16E package. Industrial temperature versions are tested and guaranteed to operate from a -40°C to 125°C operating junction temperature. All versions are available from stock.