LT8610A/LT8610AB Series 42V, 3.5A Synchronous Step-Down Regulator with 2.5µA Quiescent Current FEATURESDESCRIPTION n LT8610 Feature Set, Plus: The LT®8610A/LT8610AB series are compact, high ef- 3.5A Maximum Output Current ficiency, high speed synchronous monolithic step-down Fast 30ns Minimum Switch-On Time switching regulators that consume only 2.5µA of quies- Improved Burst Mode Efficiency (LT8610AB Only) cent current. Compared to the LT8610, they have higher Improved EMI maximum output currents of 3.5A and a faster minimum n Wide Input Voltage Range: 3.4V to 42V switch-on time of 30ns. The LT8610A has the same low n Ultralow Quiescent Current Burst Mode® Operation: ripple burst mode performance of the LT8610, while the 2.5μA IQ Regulating 12VIN to 3.3VOUT LT8610AB has even higher light load efficiency. n Fixed Output Voltages: 3.3V, 5V The other features of the LT8610 remain unchanged in the n Output Ripple < 10mVP-P (LT8610A Only) LT8610A/LT8610AB series. A SYNC pin allows synchroni- n High Efficiency Synchronous Operation: zation to an external clock. The EN/UV pin has an accurate 95%Efficiency at 1A, 5VOUT from 12VIN 1V threshold for VIN undervoltage lockout or shut down. 93%Efficiency at 1A, 3.3VOUT from 12VIN A capacitor on the TR/SS pin programs the output voltage n Low Dropout Under All Conditions: 200mV at 1A ramp rate during startup. The PG flag signals when VOUT n Safely Tolerates Inductor Saturation in Overload is within ±9% of the programmed output voltage as well n Adjustable and Synchronizable Frequency: as fault conditions. 200kHz to 2.2MHz n Accurate 1V Enable Pin Threshold OUTPUTMINIMUM1mA LOADCURRENTON TIMEEFFICIENCY** n Output Soft-Start and Tracking n LT8610* 2.5A 50ns 82% Small Thermally Enhanced 16-Lead MSOP Package LT8610A 3.5A 30ns 82% LT8610AB 3.5A 30ns 91% APPLICATIONS *See LT8610 data sheet. **VIN = 12V, VOUT = 3.3V, L = 4.7µH n Automotive and Industrial Supplies L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks n GSM Power Supplies of Linear Technology Corporation. All other trademarks are the property of their respective owners. TYPICAL APPLICATIONLT8610AB Efficiency at 5V5V 3.5A Step-Down ConverterOUT 100 VIN VIN BST 5.5V TO 42V 0.1µF 90 4.7µF EN/UV 4.7µH VOUT PG LT8610AB-5 SW 5V 80 47µF 3.5A SYNC BIAS ×2 70 10nF TR/SS VOUT 60 1µF EFFICIENCY (%) INTV 50 CC RT GND V 40 IN = 12V VIN = 24V 60.4k VIN = 36V 300.1 1 10 100 1000 fSW = 700kHz 8610ab TA01a LOAD CURRENT (mA) 8610ab TA01b 8610abfa For more information www.linear.com/LT8610A 1 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts
