LINEAR Manuals

This design note describes a dual smart battery charger for use in server battery backup. The circuit can charge batteries at up to 4A and switch continuously down to zero load currents. The circuit takes advantage of ceramic capacitors’ space saving features without sacrificing circuit performance.

This design note presents a simple, compact, and high efficiency LED flashlamp circuit suitable for use in cellular telephones and cameras. The circuit uses the LT ®3468-1 as the main controller.

The LT1991 is a flexible part that can be configured into inverting, noninverting, difference amplifiers, and even buffered attenuators, just by strapping its pins. It provides you with internal precisely matched resistors and feedback capacitors, so you can easily configure it into hundreds of different gain circuits without external components.

This document introduces a high power LED camera flash solution for cell phone applications. The solution uses LED flash lights, which are small and efficient, and can meet the various needs of cell phones for flash lights.

The LT ®1943 is a highly integrated, 4-output regulator designed to power large TFT LCD panels. It employs switching regulators—instead of linear regulators—to minimize power dissipation and accommodate a wide input voltage range. The wide input range, 4.5V to 22V, allows it to accept a variety of power sources, including the commonly used 5V, 12V and 19V AC adapters. The first buck regulator provides a logic voltage with up to 2A of current. The other three switching regulators provide the three bias voltages, AVDD, VON and VOFF, required by LCDs. All four regulators are synchronized to a 1.2MHz internal clock, allowing the use of small, low cost inductors and ceramic capacitors. Since different types of panels may require different bias voltages, all output voltages are adjustable for maximum flexibility. Programmable soft-start capability is included in all outputs to limit inrush current. The LT1943 has a built-in start-up sequence and panel protection feature. The LT1943 is available in a low-profile 28-pin TSSOP package.

The LT6650 is a low power voltage reference with an output voltage range of 0.4V to 18V. It can be used in single supply and low dropout mode, and has a two-resistor programmable output.

This document introduces the LT ®3434, 3A monolithic buck switching regulator, which is designed to optimize efficiency over all current and voltage levels, both high and low, while having low quiescent current and low dropout. Micropower bias current and Burst Mode ® operation enable it to consume merely 100µA at zero load and 12V input. The high efficiency bipolar NPN power switch (0.1Ω) provides up to 85% efficiency at a 2A load current. Combined with high duty cycle, the low dropout of the switch maintains a regulated 3.3V output down to 4V input at all load currents.

This document introduces the features of the LT3428, a dual phase boost converter that can start up at 1.5V and output 2A at 5V. The converter operates at 2MHz and has very low output ripple and few components.

This document introduces the op amp selection guide for optimum noise performance by Linear Technology, including noise characteristics, thermal noise of resistors, and quantifying resistor noise.

The LT ®3464 is an ideal choice for portable devices which require a tiny, efficient and rugged step-up con- verter.

This document introduces a dual DC/DC converter with integrated Schottky diodes, which generates ±40V outputs and consumes only 40µA quiescent current. The converter is suitable for portable devices with high accuracy and wide input and output voltage ranges.

This design note describes a simple battery charger/PowerPath™ controller (LTC4055) that augments the peak output power of a PoE regulator (LTC4267) to overcome PoE power constraints.

This document introduces the PCB layout recommendations for LT5515, including isolation measures for LO and RF signals

This document describes a high-voltage bipolar monolithic step-down converter with high efficiency and low quiescent current at light loads. The product has a wide input voltage range and a high-efficiency power switch, making it suitable for battery-powered applications and automotive applications.