Press Release Summary:
Model LTC3252 spread spectrum, step-down DC/DC converter can deliver 250 mA continuous output to 2 separate channels. It operates from 2.7-5.5 V, making it suitable for single cell Li-Ion or multi-cell NiMH/Alkaline applications. Both outputs are resistor programmable from 0.9-1.6 V. Switched capacitor fractional conversion enables it to attain efficiencies as high as 88%. Switching frequency randomly shifts within 1.0-1.6 MHz range to minimize harmonics.
Original Press Release:
Dual Output, Spread Spectrum, Step-Down DC/DC Converter Delivers 250mA per Channel without Inductors
MILPITAS, CA - July 9, 2003 - Linear Technology Corporation announces the LTC3252, an inductorless, spread spectrum, step-down DC/DC converter, which can deliver up to 250mA continuous output current to two separate channels. It operates from a VIN range of 2.7V to 5.5V, making it ideal for single cell Li-Ion or multi-cell NiMH/Alkaline applications. Both outputs are resistor programmable from 0.9V to 1.6V, making it ideal for driving low voltage DSPs and microcontrollers. Its switched capacitor fractional conversion enables it to attain efficiencies as high as 88%. The combination of ultra-low noise, high efficiency and a very compact/low profile footprint make it ideal for handheld wireless designs that require low noise and optimum battery life, operate without inductors.
The LTC3252 utilizes the power industry's first 2-phase spread spectrum switching architecture to provide a very low noise regulated output as well as low noise at the input. The switching frequency randomly shifts within the 1.0MHz to 1.6MHz frequency range to minimize harmonics, which could introduce noise into surrounding wireless circuitry. The LTC3252 has three operating modes: Continuous Spread Spectrum, Spread Spectrum with Burst Mode® operation, and shutdown. Low quiescent current of 60uA (in Burst Mode operation) and <1uA in shutdown maximize battery run-time. Its 4x3mm DFN package and a low external parts count keep the profile under 0.8mm, and the solution footprint under 35mm2 making the LTC3252 ideally suited for space-constrained handheld applications.
The LTC3252 is available from stock in DFN-12 package. Pricing starts at $2.60 each in 1,000-piece quantities.
Summary of Features: LTC3252
Low Noise, 2-Phase Spread Spectrum Switching Architecture
Dual 250mA Current Outputs
Up to 88% Efficiency
No Inductors are Required
2.7V to 5.5V Input Voltage Range
Output Voltage: 0.9V to 1.6V
Spread Spectrum Frequency Range: 1 MHz to 1.6MHz
Supply Current Only 60uA, Shutdown <1uA
Solution Footprint <35mm², Profile <0.8mm
Available in a 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 frequency devices. 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.