Solutions Search - Flyback, Forward and Isolated Controllers
No-Opto Isolated Flyback Converters
Jun 10th 2016
The no-opto isolated flyback parts from Linear need no opto-coupler or LT1431 shunt regulator for regulation. They sense the isolated output voltage directly from the primary-side waveform. This simplifies the design, allows for a smaller solution size and only requires one component crossing the isolation barrier. The load, ...
Differences Between the Ćuk Converter and the Inverting Charge Pump Converter
Mar 7th 2016
The Ćuk converter (also referred to as the two inductor inverting converter), the inverting charge pump and the single inductor inverting converter (also referred to as the inverting buck-boost) all provide a negative output voltage from a positive input voltage. However, engineers often unknowingly refer to these topologies ...
Monolithic Converter Delivers High Output Voltages
Nov 4th 2015
Design Note 545: Introduction
Industrial, telecom, medical and automotive applications use a wide variety of regulated voltages to operate effectively, including high voltage and negative rails. When the designer is faced with producing industrial power supplies, the job can be simplified by minimizing the parts count, as well ...
LT3753 9V-15V Input to 54V/3A Isolated Forward Converter
Feb 26th 2015
The LT®3753 is a primary side, current-mode PWM controller optimized for an active clamp forward converter topology. It features a programmable volt-second clamp that provides a duty cycle guardrail to limit primary switch reset voltage and prevent transformer saturation during load transients. The LT3753 also features ...
LT3752/LT8311 48Vin, 24Vout Active Clamp Forward Converter with High Light Load Efficiency
Feb 11th 2015
The LT3752 includes a number of programmable features that make it suitable for this application. For instance, programmable delays between various gate signals is used to prevent cross-conduction and to optimize efficiency, and programmable turn-on current spike blanking (adaptive leading edge blanking plus programmable extended ...
LT3798/LT8309 5V, 2A Energy Star Compliant Isolated Converter
Feb 10th 2015
The focus of this circuirt was to take a design based on the LT®3798 and make it Energy Star Compliant; reduce no load, standby power to less than 300mW. That was achieved by adding the components highlighted in the dotted line box in the schematic inside the primary side. This circuit is simply a switch that removes ...
LT8310/LT1431 81 Watt Isolated Nonsynchronous Forward Converter with Opto Feedback
Jan 30th 2015
The LT8310 is a constant-frequency resonant reset forward converter controller with a low side N-channel MOSFET gate driver. The LT8310 has a wide input voltage range from 6V to 100V. Its switching frequency can be programed from 100kHz to 500kHz to optimize efficiency, performance or external component size. The LT8310's protection ...
LT3752/LT8311 240W Isolated Forward Converter
Jul 28th 2014
The LT3752 includes a number of programmable features that make it suitable for this application. For instance, programmable delays between various gate signals is used to prevent cross-conduction and to optimize efficiency, and programmable turn-on current spike blanking (adaptive leading edge blanking plus programmable extended ...
19V-29V input to 48V/2A Isolated Forward Converter using LT3753
Jul 28th 2014
The LT3753 is a primary side, current-mode PWM controller optimized for an active clamp forward converter topology. It features a programmable volt-second clamp that provides a duty cycle guardrail to limit primary switch reset voltage and prevent transformer saturation during load transients. The volt-second clamp also limits ...
LTspice: Simple Steps for Simulating Transformers
Jul 1st 2014
Here is the simple approach to simulate a transformer in LTspice IV:
Draft an inductor for each transformer winding
Couple them using a single mutual inductance (K) statement via a SPICE directive:
K1 L1 L2 L3 1
The last entry in the K statement is the coupling coefficient, which can vary between 0 and 1, where 1 represents ...
Miniature Isolated Solution Using LT8301 and Coupled Inductor
Jun 19th 2014
Customers that require miniature solutions with only functional isolation often choose isolated modules. These solutions have very bulky form factors, and typically do not provide high power efficiency or a low no-load input current. In addition, the output voltages of these modules are usually unregulated, having large VOUT ...
The Low Output Voltage Ripple Zeta DC/DC Converter Topology
Apr 28th 2014
In the world of switching DC/DC converters the Zeta topology is a lesser known relative of the SEPIC topology. Both converters provide a positive output voltage that can be greater than, equal to or less than VIN while avoiding the complexity and cost of a buck-boost converter. The Zeta converter however, has the advantage of ...
Monolithic No-Opto Isolated Flyback Converter Provides Versatile Solution
Feb 19th 2014
Introduction
Traditionally, isolated power supplies use an optocoupler in the feedback loop to transfer regulation information across the isolation barrier. Unfortunately, an opto-coupler’s gain characteristic varies widely over temperature and lifetime, increasing the difficulty of power supply loop compensation.
Linear ...
Micropower Isolated Flyback Converter with Input Voltage Range from 6V to 100V
Dec 1st 2012
Introduction
Flyback converters are widely used in isolated DC/DC applications because of their relative simplicity and low cost compared to alternative isolated topologies. Even so, designing a traditional flyback is not easy—the transformer requires careful design, and loop compensation is complicated by the well known ...
Loading