Analog Devices LTC7149

Description

The LTC®7149 is a high efficiency 60V, 4A synchronousmonolithic step-down regulator for inverting outputapplications. The regulator features a single resistorprogrammableoutput voltage and high efficiency over awide VOUT range.The inverting regulator operates from an input voltagerange of 3.4V to 60V and provides an adjustable outputfrom (–28V) to zero volts while delivering up to 4A ofinductor current. The switching frequency is also setwith an external resistor. A user-selectable mode input isprovided to allow the user to trade off ripple noise for efficiencyat light loads; Burst Mode operation provides thehighest efficiency at light loads, while forced continuousmode provides low output ripple. The MODE/SYNC pincan also be used to synchronize the switching frequencyto an external clock. Internal level-shift circuits allow theI/O pins (RUN, MODE/SYNC, PGOOD) to be referencedto board GND.The LTC7149 operates with a peak current mode architecturethat allows for fast transient response with inherentcycle-to-cycle current limit protection.

Features

Wide VIN Range: 3.4V to 60VWide VOUT Range: 0V to –28VSingle Resistor VOUT ProgrammingIntegrated 110mΩ Top N-Channel/50mΩ Bottom N-Channel MOSFETsRegulated IQ: 440μA, Shutdown IQ: 15μABoard GND Referenced I/O Pins (RUN, PGOOD, MODE/SYNC)Accurate Resistor Programmable Frequency (300kHz to 3MHz) with ±50% Frequency Sync Range92% Efficiency with 12 VIN and –5VOUT±0.8% Output Voltage AccuracyPeak Current Mode OperationBurst Mode® Operation, Forced Continuous ModeProgrammable Soft-StartOvertemperature ProtectionAvailable in 28-Lead (4mm x 5mm) QFN and TSSOP Packages

Typical applications

• Industrial Applications
• Distributed Power Systems
• Telecom Power Supplies

More information

• Datasheet
• IC product information