Analog Devices LT8494

Description

The LT®8494 is an adjustable frequency (250kHz to 1.5MHz)monolithic switching regulator. Quiescent current can beless than 7μA when operating and is ~0.3μA when SWENis low. The LT8494 can be configured as either a SEPIC,boost or flyback converter.The low ripple Burst Mode operation maintains highefficiency at low output current while keeping outputripple below 10mV. Dual supply pins (VIN and BIAS) allowthe part to automatically operate from the most efficientsupply. Input supply voltage can be up to 60V for SEPICtopologies and up to 32V (with ride-through up to 60V)for boost and flyback topologies. After start-up, batterylife is extended since the part can draw current from itsoutput (BIAS) even when VIN voltage drops below 2.5V.Using a resistor divider on the SWEN pin provides a programmableundervoltage lockout (UVLO) for the converter.A power good flag signals when VOUT reaches 92% of theprogrammed output voltage.Additional features such as frequency foldback and softstartare integrated. The LT8494 is available in 20-leadQFN and 20-lead TSSOP packages with exposed padsfor low thermal resistance. Fault tolerance in the TSSOPallows for adjacent pin shorts or an open without raisingthe output voltage above its programmed value.

Features

Low Ripple Burst Mode® Operation:7μA IQ at 12VIN to 5VOUTOutput Ripple (<10mV Typ.)Dual Supply Pins:Improves EfficiencyReduces Minimum Supply Voltage to ~1V afterStart-Up to Extend Battery LifeWide Input Voltage Range of ~1V to 60V (2.5V to32V for Start-Up)PG Functional for Input Supply Down to 1.3VFMEA Fault Tolerant in TSSOP PackageFixed Frequency PWM, SEPIC/BOOST/FLYBACKTopologiesNPN Power Switch: 2A/70VProgrammable Switching Frequency: 250kHz to 1.5MHzUVLO Programmable on SWEN PinSoft-Start Programmable with One CapacitorSmall 20-Lead QFN or 20-Lead TSSOP Packages

Typical applications

• Power for Portable Products
• Automotive ECU Power
• Industrial Supplies

More information

• Datasheet
• IC product information