Stepping Parameters in LTspice IV
with Gabino Alonso, Strategic Marketing

Plotting voltages or currents in a simulation is important but so is varying a parameter in a device or model so that you can compare performance and develop your circuit intuition. There are two ways to examine a circuit by changing the value of a parameter. You can either manually enter each value then re-simulate the circuit or you can use the .step command to sweep across a range of values in a single simulation run and have a side by side comparison.

This video provides an overview of the basics steps of how to use the .STEP command to perform repeated analysis of a circuit in LTspice IV.

Bob Dobkin Analog Interview
with Bob Dobkin, Vice President, Engineering & Chief Technical Officer

Linear Technology Chief Technical Officer Bob Dobkin discusses analog design challenges and circuit design approaches.

Switching Regulator Power Loss
with Bob Dobkin, Vice President, Engineering & Chief Technical Officer

Efficiency is a misleading number for comparison of switching regulators. The efficiency number can be manipulated by the input and output voltage, while power loss is more tightly tied to the actual circuit. This video explains why.

Application Notes Ease Analog Design
with Robert Dobkin, Vice President of Engineering & CTO

Linear Technology co-founder and Chief Technical Officer Bob Dobkin discusses the evolution of analog electronics design and the role of application notes and books in assisting designers in building circuits.

Analog Circuit Design - A Tutorial Guide to Applications and Solutions
Edited by Robert Dobkin and Jim Williams

Isolated Flyback Controller with PFC Controls Voltage or Current
with Jesus Rosales, Applications Engineer, Power Products

Linear Technology’s LT®3798 isolated controller with active power factor correction (PFC) is specifically designed for regulating bus voltages or driving constant current applications over a wide input range of 10V to 480V. It is ideal for constant voltage/current applications requiring 4W to over 100W power.

The LT3798’s unique current sensing scheme delivers a well regulated voltage or current to the secondary side with no optocoupler. It also offers low harmonic distortion while delivering efficiencies as high as 90%. Output short circuit protection ensures long term reliability and a simple, compact solution footprint addresses a wide range of applications.

Transform a DC/DC Converter into a High Performance, Full-Featured Battery Charger
with David Burgoon Applications Engineer, Power Products

Portable electronic devices, powered by batteries, require battery chargers. In higher powered applications, efficiency and thermal management requirements lead to solutions using DC/DC converters. DC/DC converter controllers do not have the accuracy and features required for advanced battery charging and PowerPath™ management.

Linear Technology’s LTC®4000 has the accuracy and features required to turn a DC/DC converter into a high performance battery charger with features such as charge current and input current regulation, charge voltage and system voltage regulation, C/X or timer termination, trickle charge, temperature qualified charging, instant on and ideal diode/ PowerPath control. It handles a wide variety of applications with input and output voltages from 3V to 60V.

The LTC®4000 easily adds these capabilities to a typical DC/DC converter.

Adding Third-Party Models to LTspice IV
with Gabino Alonso, Strategic Marketing

LTspice IV supplies many device models to include discrete like transistors and MOSFET models. Nevertheless, there are also many third-party models from manufacturers that are available that you could add to your LTspice IV circuit simulations. These third-party SPICE models are described with a .MODEL and .SUBCKT statements. Models given as .MODEL statements are for intrinsic SPICE devices like diodes and transistors. Whereas models given by .SUBCKT statements define the component by a collection of circuitry of intrinsic SPICE devices.

This video provides an overview of how to add a third-party .MODEL statement for an intrinsic SPICE device and how to add and create a symbol for a a third party .SUBCKT statement to LTspice IV.

Linear Technology 30th Anniversary Video
with Bob Swanson, Robert Dobkin, Lothar Maier

Video Interview with Linear Co-founders Bob Swanson and Bob Dobkin, and CEO Lothar Maier on the 30th anniversary of the founding of Linear Technology

LTC3634 Dual 15V, 3A Monolithic Step-Down Regulator for DDR Power
with Jeff Gruetter, Senior Product Marketing Engineer, Power Products

The LTC®3634 is a high efficiency, dual-channel monolithic synchronous step-down regulator which provides power supply and bus termination rails for DDR1, DDR2, and DDR3 SDRAM controllers. The operating input voltage range is 3.6V to 15V, making it suitable for point-of-load power supply applications from a 5V or 12V input, as well as various battery powered systems. Both channels can source and sink 3A of output current.

The VTT regulated output voltage is equal to VDDQIN• 0.5. An on-chip buffer capable of driving a 10mA load provides a low noise reference output (VTTR) also equal to VDDQIN • 0.5

The LTC3634 is offered in both 28-pin 4mm × 5mm QFN and 28-pin exposed pad TSSOP packages.

Offline Isolated Flyback LED Controller with Active PFC
with Wei Gu

The LT®3799/-1 isolated LED controller with active power factor correction (PFC) is specifically designed for driving LEDs over a wide input range of 24V to 480V+. It is ideal for LED applications requiring 4W to over 100W of LED power. The LT3799/-1’s unique current sensing scheme delivers a well regulated current to the secondary side with no optocoupler. The LT3799 is compatible with standard TRIAC in-wall dimmers while the LT3799-1 optimizes line regulation. It also offers low harmonic distortion while delivering efficiencies as high as 90%. Open and short LED protection ensures long term reliability and a simple, compact solution footprint addresses a wide range of applications.