36V, 2A(IOUT), 2.8MHz Step-Down DC/DC Converter Offers Quiescent Current of Only 50uA

LTC News for Immediate Release
For more information, tel. 408-432-1900
Doug Dickinson, Media Relations Mgr., ext. 2233
John Hamburger, Dir., Mkting Comm., ext. 2419
36V, 2A(IOUT), 2.8MHz Step-Down DC/DC Converter
Offers Quiescent Current of Only 50uA
MILPITAS, CA – May 17, 2006 – Linear Technology Corporation announces the LT3481, a 2A,
36V step-down switching regulator with Burst Mode® operation to keep quiescent current under
50uA. The LT3481 operates within a VIN range of 3.6V to 34V, making it ideal for load dump
and cold-crank conditions found in automotive applications. Its 3.2A internal switch can deliver
up to 2A of continuous output current to voltages as low as 1.26V. The LT3481’s Burst Mode
operation offers ultra-low quiescent current, well suited for applications such as automotive or
telecom systems, which demand always-on operation and optimum battery life. Switching
frequency is user programmable from 300kHz to 2.8MHz, enabling the designer to optimize
efficiency while avoiding critical noise-sensitive frequency bands. The combination of its 3mm x
3mm DFN-10 package (or thermally enhanced MSOP-10E) and high switching frequency keeps
external inductors and capacitors small, providing a compact, thermally efficient footprint.
The LT3481 utilizes a high efficiency 3.2A, 0.18Ohm switch, with the necessary boost
diode, oscillator, control and logic circuitry integrated into a single chip. Low ripple Burst Mode
operation maintains high efficiency at low output currents while keeping output ripple below
15mVPK-PK. Special design techniques enable high efficiency over a wide input voltage range and
the devices’s current mode topology enables fast transient response and excellent loop stability.
Other features include external synchronization (from 275kHz to 475kHz), a power good flag
and soft-start capability.
Pricing for the LT3481EDD and LT3481EMSE starts at $3.25 each, for 1,000-piece
quantities. The LT3481IDD and LT3481IMSE are tested and guaranteed to operate from a -40°C
to 125°C operating junction temperature, priced at $3.90each in 1,000-piece quantities. All
versions are available from stock.
36V, 2A(IOUT), 2.8MHz Step-Down DC/DC Converter
Offers Quiescent Current of Only 50uA
Page 2
Photo Caption: 34V, 2A (IOUT), 2.8MHz Step-Down Switching Regulator with IQ<50uA in
3mm x 3mm DFN
Summary of Features: LT3481
• Wide Input Range: 3.6V to 36V Operating
• 2A Maximum Output Current
• Low Ripple Burst Mode Operation
- 50uA at 12VIN to 3.3VOUT
- Output Ripple < 15mV
• Adjustable Switching Frequency: 300kHz to 2.8MHz
• Low Shutdown Current: IQ < 1uA
• Integrated Boost Diode
• Power Good Flag
• Saturating Switch Design: 0.18Ohm On-Resistance
• 1.265V Feedback Reference Voltage
• Output Voltage: 1.265V to 20V
• Soft-Start Capability
• Synchronizable Between 275kHz to 475kHz
• Small 10-Pin Thermally Enhanced MSOP and (3mm x 3mm) DFN-10 Packages
Company Background
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, 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. For more information, visit www.linear.com
Doug Dickinson, Media Relations Manager
Linear Technology Corporation
1630 McCarthy Boulevard
Milpitas, CA 95035-7417
[email protected]
READER SERVICE: Call toll-free 1-800-4-LINEAR (for literature only), or go to the company’s web site:
Note: LT, LTC, Burst Mode and
are registered trademarks of Linear Technology Corp.