LINEAR Manuals

Linear Technology offers two new buck regulators that operate from a wide input voltage range (3.6V to 36V) and take so little space that they easily solve many difficult power supply problems. The LT®1936 and LT1933 are perfect for applications with disparate power inputs or wide range input power supplies such as automotive batteries, 24V industrial supplies, 5V logic supplies and various wall adapters. Both parts are monolithic current mode PWM regulators which provide excellent line and load regulation and dynamic response. They operate at a 500kHz switching frequency, enabling the use of small, low cost inductors and ceramic capacitors, resulting in low, predictable output ripple.

Low Distortion, Low Noise Differential Amplifier Drives High Speed ADCs in Demanding Communications Transceivers

This document describes a solution to control inrush current using the LT3467 ThinSOT TM switching regulator. The LT3467 integrates a soft-start function with a built-in 42V, 1.1A switch. By enabling the soft-start feature, the inrush current can be limited to prevent input source collapse and output overshoot.

This document describes the features and functions of a high-accuracy synchronous step-down controller, including output voltage tracking and programmable margining. The controller is suitable for power supply designs for high-performance servers, ASICs, and memory systems. It has a wide operating range and high accuracy, with input voltages ranging from 4V to 32V and output voltages ranging from 0.6V to 2.5V, with a reference voltage accuracy of ±0.67%. The controller uses a constant on-time, valley current mode control architecture, allowing it to operate at very low duty cycles with fast transient response. Additionally, it has an optional current sensing resistor for high efficiency or most accurate current limit.

This document describes how to replace ORing diodes with MOSFETs to reduce heat and save space. By using the LTC4354 negative voltage diode-OR controller, near-ideal diode behavior can be achieved, and external N-channel MOSFETs are used to replace the diodes. This design reduces power dissipation, saves board space, and increases the input operating range.

LT3466 is a dual step-up converter capable of driving up to 20 white LEDs with a programmable constant current. The device is also capable of driving asymmetric LED strings with independent dimming and shutdown control for multipanel LCD backlight applications. The LT3466 uses a constant-current, step-up architecture to directly regulate LED current, providing consistent light intensity and color across all LEDs regardless of variations in their forward voltage drop. Important features including soft-start, open LED protection, adjustable switching frequency and DC dimming control are integrated into the part, making the LT3466 LED driver an ideal solution for space-constrained portable devices such as cellular phones, PDAs and digital cameras.

This design note describes a new approach to precision LVDT signal conditioning that combines an LTC1967 RMS to DC converter with a separate phase detector circuit. This approach eliminates the losses and errors associated with traditional demodulation methods and also eliminates the complexity and cost associated with phase-locked loops.

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.

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

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 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.

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

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.