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

News Release ⎜ www.linear.com
58VIN, 2A with IOUT, 2.4MHz Step-Down DC/DC Converter Draws Only
85uA 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 85uA. 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
58VIN, 2A with IOUT, 2.4MHz Step-Down DC/DC Converter Draws Only
85uA of Quiescent Current & Withstands 80V Transients
page 2
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 -40°C to 125°C
operating junction temperature, priced at $4.18 each, in 1,000-piece quantities. The
LT3980HMSE is guaranteed to operate from a -40°C to 150°C 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.
Photo Caption: 58V with 80V Transient Protection, 2A (IOUT), 2.4MHz Step-Down Switching
Regulator with IQ<85uA in 3mm × 4mm DFN (or MSOP-16E)
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 = 85uA at 12VIN to 3.3VOUT
Adjustable Switching Frequency: 100kHz to 2.4MHz
Low Shutdown Current: IQ < 1uA
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
58VIN, 2A with IOUT, 2.4MHz Step-Down DC/DC Converter Draws Only
85uA of Quiescent Current & Withstands 80V Transients
page 3
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,
uModule® 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, uModule, Burst Mode and
are registered trademarks of Linear Technology Corp. All other
trademarks are the property of their respective owners.
Press Contacts:
North America / Worldwide
UK & Nordic
John Hamburger, Director Marketing
[email protected]
Tel 408-432-1900 ext 2419
Alan Timmins
[email protected]
Tel: +44-1-252-629937
Doug Dickinson, Media Relations Manager
[email protected]
408-432-1900 ext 2233