DC/DC Converter draws 85 µA of quiescent current.

Press Release Summary:




Operating within VIN range of 3.6-58 V, Model LT3980 includes overvoltage lockout protection against transients as high as 80 V, making device suited for load dump and cold-crank conditions found in automotive applications. Internal 3.4 A switch can deliver up to 2 A of continuous output current at voltages as low as 0.79 V. Housed in 3 x 4 mm DFN-16 package, step-down switching regulator features user-programmable switching frequency from 100 kHz to 2.4 MHz.



Original Press Release:



58VIN, 2A with IOUT, 2.4MHz Step-Down DC/DC Converter Draws Only 85µA of Quiescent Current & Withstands 80V Transients



MILPITAS, CA - September 28, 2009 - Linear Technology Corporation announces the LT3980, a 2A, 58VIN step-down switching regulator with Burst Mode® operation to maintain quiescent current under 85µA. The LT3980 operates within a VIN range of 3.6V to 58V, with overvoltage lockout protection against transients as high as 80V, making the device ideal for load dump and cold-crank conditions commonly found in automotive applications. Its internal 3.4A switch can deliver up to 2A of continuous output current at voltages as low as 0.79V. The LT3980's Burst Mode operation provides ultralow quiescent current, well suited for applications such as automotive or telecom systems, which have always-on circuits and demand optimal battery life. Switching frequency is user programmable from 100kHz to 2.4MHz, enabling the designer to maximize efficiency while avoiding critical noise-sensitive frequency bands. The combination of a 3mm x 4mm DFN-16 package (or thermally enhanced MSOP-16E) and high switching frequency keeps the LT3980's external inductor and capacitors small, providing a compact, thermally efficient footprint.

The LT3980 utilizes a high efficiency 3.4A, 200mOhm switch, with the necessary boost diode, oscillator, control and logic circuitry integrated into a single chip. Its catch diode current sense (DA pin) protects the circuit during input voltage transients even at high switching frequencies. Low ripple Burst Mode® operation maintains high efficiency at low output currents while keeping output ripple below 15mVPK-PK. Special design techniques used in the LT3980 enable high efficiency over a wide input voltage range, and the device's current mode topology enables fast transient response and excellent loop stability. Other features include external synchronization (from 250kHz to 2MHz), a power good flag and soft-start capability.

Pricing for the LT3980EDE and LT3980EMSE starts at $3.55 each, for 1,000-piece quantities. The LT3980IDE and LT3980IMSE are guaranteed to operate from a -40ºC to 125ºC operating junction temperature, priced at $4.18 each, in 1,000-piece quantities. The LT3980HMSE is guaranteed to operate from a -40ºC to 150ºC operating junction temperature and is priced at $4.43 in 1,000 piece quantities. All versions are available from stock. For more information, visit www.linear.com.

Summary of Features: LT3980

Wide Input Range: Operation from 3.6V to 58V

Overvoltage Lockout Protects Circuits Through 80V Transients

2A Maximum Output Current

Low Ripple (<15mVP-P) Burst Mode® Operation:

IQ = 85µA at 12VIN to 3.3VOUT

Adjustable Switching Frequency: 100kHz to 2.4MHz

Low Shutdown Current: IQ < 1µA

Catch Diode Current Sense Protects Circuit Through Short-Circuit & Input Overvoltage

Synchronizable Between 250kHz to 2MHz

Power Good Flag

Saturating Switch Design: 200mOhm On-Resistance

Thermal Protection

Soft-Start Capability

Small 16-Pin Thermally Enhanced MSOP & 3mm - 4mm DFN Packages

58V with 80V Transient Protection, 2A (IOUT), 2.4MHz Step-Down Switching Regulator with IQ<85µA in 3mm - 4mm DFN (or MSOP-16E)

About Linear Technology

Linear Technology Corporation, a manufacturer of high performance linear integrated circuits, was founded in 1981, became a public company in 1986 and joined the S&P 500 index of major public companies in 2000. Linear Technology products include high performance amplifiers, comparators, voltage references, monolithic filters, linear regulators, DC-DC converters, battery chargers, data converters, communications interface circuits, RF signal conditioning circuits, µModule® products, and many other analog functions. Applications for Linear Technology's high performance circuits include telecommunications, cellular telephones, networking products such as optical switches, notebook and desktop computers, computer peripherals, video/multimedia, industrial instrumentation, security monitoring devices, high-end consumer products such as digital cameras and MP3 players, complex medical devices, automotive electronics, factory automation, process control, and military and space systems.
LT, LTC, LTM, µModule, Burst Mode and are registered trademarks of Linear Technology Corp. All other trademarks are the property of their respective owners.

North America and General Information

John Hamburger

Tel: (408) 432-1900 ext. 2419

jhamburger@linear.com

Doug Dickinson

Tel: (408) 432 1900 ext. 2233

ddickinson@linear.com

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