3.3A, 2.5MHz, 42V Boost/Inverting DC/DC Converter with Fault Protection

News Release ⎜ www.linear.com
3.3A, 2.5MHz, 42V Boost/Inverting DC/DC
Converter with Fault Protection
MILPITAS, CA – April 7, 2010 – Linear Technology Corporation announces the LT3581, a
current mode, fixed frequency step-up DC/DC converter with integrated fault protection features
for output shorts, input/output overvoltages, and overtemperature conditions. The LT3581 uses
two integrated 42V switches – a 1.9A master switch and a 1.4A slave switch – which can be tied
together for a total limit of 3.3A. The LT3581 operates from an input voltage range of 2.5V to
22V, with transient protection to 40V, making it suitable for applications with input sources
ranging from a single-cell Li-Ion to automotive inputs. The LT3581 is ideal for many local
power supply designs as it can be configured as either a boost, SEPIC or an inverting converter.
The combination of a 4mm x 3mm DFN package (or MSOP-16E) and tiny externals ensures a
very compact footprint while minimizing solution cost.
The LT3581’s low VCESAT switches, 0.25V (tied together at 2.75A), deliver efficiencies
up to 88%. With both switches combined and from a 5V input, the LT3581 can deliver up to
830mA at 12V or 625mA at -12V. For high voltage outputs, the LT3581’s slave switch enables
high power charge pump topologies which are very efficient and require few external
components. The LT3581’s switching frequency can be programmed via a single resistor or
synchronized to an external clock between 200kHz and 2.5MHz, minimizing external component
sizes and avoiding “noise critical” frequency bands. Undervoltage lockout (UVLO) is user
adjustable for optimal system performance. A single feedback resistor sets the output voltage,
3.3A, 2.5MHz, 42V Boost/Inverting DC/DC
Converter with Fault Protection
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minimizing external components. Other features include external synchronization capability and
junction temperature monitoring.
The LT3581EDE is available in a 4mm x 3mm DFN-14 package, priced starting at $2.45
each for 1,000 piece quantities. The LT3581EMSE is also available in a thermally enhanced
MSOP-16 package, priced starting at $2.55 each for 1,000 piece quantities. Industrial
temperature (-40°C to 125°C) versions, the LT3581IDE and the LT3581IMSE, are also available
from stock. Pricing starts at $2.72 and $2.83 each, respectively, for 1,000 piece quantities. For
more information, visit www.linear.com.
Photo Caption: 3.3A, 42V Boost, Inverting or SEPIC DC/DC Converter
Summary of Features: LT3581
3.3A, 42V Combined Power Switch
Master/Slave (1.9A/1.4A) Switch Design
Output Short Circuit Protection
Wide Input Range: 2.5V to 22V Operating, 40V Maximum Transient
Switching Frequency Up to 2.5MHz
Easily Configurable as a Boost, SEPIC, Inverting or Flyback Converter
User Configurable Undervoltage Lockout
Low Vcesat Switch: 250mV at 2.75A (Typical)
Can be Synchronized to External Clock
Can Be Synchronized to other Switching Regulators
High Gain SHDN Pin Accepts Slowly Varying Input Signals
14-Pin 4mm × 3mm DFN & 16-Lead MSE Package
3.3A, 2.5MHz, 42V Boost/Inverting DC/DC
Converter with Fault Protection
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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 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