Press Release Summary:
Model LTC3441 synchronous, fixed frequency converter offers efficiencies up to 95%, optimizing battery run time for battery-powered applications. It operates from input voltage of 2.4-5.5 V and can provide up to 1 A at fixed output voltage between 2.4-5.25 V. Buck-Boost topology allows unit to operate above, below, and equal to output voltage with single inductor. Operating frequency is set internally to 1 MHz and can be synchronized up to 2 MHz.
Original Press Release:
95% Efficient Buck-Boost DC/DC Converter Delivers up to 1Amp
MILPITAS, CA - August 4, 2003 - Linear Technology Corporation announces the LTC3441, a true Buck-Boost DC/DC converter, which can deliver up to 1 amp of output current at efficiencies as high as 95%. The LTC3441 is a synchronous, fixed frequency, Buck-Boost DC/DC converter designed to optimize battery run time for single cell Li-Ion, multi-cell alkaline or NiMH battery powered applications. It operates from an input voltage range of 2.4V to 5.5V and can provide up to 1A of output current at a fixed output voltage between 2.4V to 5.25V.
A unique Buck-Boost topology allows the LTC3441 to operate above, below and equal to the output voltage with a single inductor, providing a continuous transfer function through all the operating modes, as the battery voltage declines. The operating frequency is set internally to 1MHz and can be synchronized up to 2MHz, allowing the use of tiny surface mount components and maintaining the switching noise well above the pass-band of most communication systems. The small implementation footprint makes it ideal for space-constrained environments such as cellular phones, PDAs, wireless and DSL modems and digital cameras.
The LTC3441 uses two 0.10 Ohm N-channel and two 0.11 Ohm P-channel switches in a constant frequency, synchronous switching topology to obtain efficiencies as high as 95%. The LTC3441's selectable Burst Mode® operation allows the internal power MOSFETs to operate intermittently based on load demand and reduces the quiescent current to a low 25uA when there is no load (less than 1uA in shutdown). Furthermore, the selectable Burst Mode operation is inhibited during synchronization or when the SYNC/MODE pin is pulled low, preventing low frequency ripple from interfering with audio circuitry. The LTC3441 also features anti-ringing control to minimize EMI, soft-start control and thermal shutdown. The combination of the tiny solution footprint and Buck-Boost topology make the LTC3441 ideal for handheld applications, which require both optimum battery run-time and small size.
The LTC3441 is available from stock in a 4x3mm DFN package. Pricing starts at $3.55 each in 1,000-piece quantities.
Summary of Features: LTC3441
Fixed Frequency Operation with Input Voltages Above, Below or Equal to the Output
Up to 1A Continuous Output Current
Single Inductor, No Schottky Diodes Required
Only 25uA Quiescent Current In Burst Mode Operation
2.4V to 5.5V Input Voltage Range
2.4V to 5.25 Output Voltage Range
1MHz Constant Switching Frequency
Selectable Burst Mode Operation/ Pulse Skipping Mode
Low Shutdown Current <1uA
4x3mm DFN-12 Package
Linear Technology Corporation was founded in 1981 as a manufacturer of high performance linear integrated circuits. Linear Technology products include operational, instrumentation and audio amplifiers; voltage regulators,power management devices, DC-DC converters and voltage references; comparators; monolithic filters; communications interface circuits; one-chip data acquisition sub-systems; pulse-width modulators and sample-and-hold devices; and high frequencydevices. Applications for Linear Technology's high performance circuits include wireless and broadband telecommunications infrastructure, cellular telephones, networking products and satellite systems, notebook and desk top computers, computer peripherals, video/multimedia, industrial and medical instrumentation, automotive electronics, factory automation, process control, military and space systems, and high-end consumer products including digital cameras, MP3 players and other electronic products.