App note(PDF) from NXP on DC-DC medium power small-signal MOSFETs.
This application note explores different methods of DC-to-DC conversion. It includes some examples of DC-to-DC down-converters using small-signal MOSFETs.
App note: Medium power small-signal MOSFETs in DC-to-DC conversion - [Link]
Susan Nordyk @ edn.com:
Encapsulated in a tiny 9.0×6.5×1.83-mm QFN package, the ISL8203M step-down DC/DC power module from Intersil furnishes an adjustable output voltage between 0.8 V to 5 V to allow designers to use one device to build a single 6-A or dual 3-A output power supply. The ISL8203M simplifies power-supply design for FPGAs, ASICs, microprocessors, DSPs, and other point-of-load conversions in communications, test and measurement, and industrial systems.
Intersil shrinks step-down DC/DC power module - [Link]
Linear Technology Corporation announces the LTC3371, a highly integrated general-purpose power management solution for systems requiring multiple low voltage power supplies. The device features four synchronous buck converters, each powered from independent 2.25 V to 5.5 V inputs, and each configurable to share up to four of eight available 1 A power stages. With eight unique output current configurations, the LTC3371 provides substantial flexibility and ease of reuse across many different applications. The device is ideal for a wide variety of multichannel industrial, automotive, communications and distributed power systems.
Configurable Buck DC/DCs Deliver a Total of 8A from 2 to 4 Independent Outputs for Power System Flexibility - [Link]
Switch-mode regulator Traco TSR 0.5 will give you as much as you need. If you have an application, where 0.5A is sufficient, then the new series of DC/DC modules is ideal for you.
Maybe, it´s worth to ask a question, whether it makes sense to use a switch-mode regulator for such a low current? For sure yes, at least because of two reasons. If we need to create 3.3V from for example 12V, then at a current of 0.5A a power loss of 4.35W appears at a classic linear regulator. That´s already a quite considerable power, able to heat up a device – especially at smaller enclosures and a dense population on a PCB.
Another reason is energy saving – especially at battery powered devices. Switch mode power supplies (SMPS) have a “genial” feature, that thanks to their high efficiency we use practically whole power drawn from a source, i.e. if we need say 5V/0.5A from a 15V source – we won´t take from it 0.5A but only approx. 0,17-0,18A.
Novelty of company Traco Electronic – series TSR 0.5 is by its function very similar to well known, proven DC/DC regulators TSR1 or TSRN1. The main difference is in a smaller allowed current and a feelingly lower price . That ´s why this series is very suitable for any application, where a current of 0.5A will be sufficient. A big advantage can be a wide operating temperatures range from -40 to +90°C (power derating 5%/K at temperature above 80°C). Maximum input voltage of 32V enables a usage even at power supplying from various alternative energy sources with a big input voltage fluctuations.
This novelty is so far available in a version with 5V output voltage (TSR 0.5-2450) and soon there will be another.
Why to pay for the current, which you won´t use? - [Link]
The LTM4625 from Linear Technology is a switching mode μModule (micromodule) regulator in a tiny 6.25 mm × 6.25 mm × 5.01 mm BGA package. Like many of the newer regulator designs, the package includes the switching controller; power FETs, inductor and support components. Operating over an input voltage range of 4 V to 20 V (or 2.375 V to 20 V with an external bias supply) the LTM4625 supports an output voltage range of 0.6 V to 5.5 V, set by a single external resistor. Its high efficiency design delivers up to 5A continuous output current. Only bulk input and output capacitors are needed.
Complete 5A step-down Regulator - [Link]
Linear Technology has squeezed a 3A voltage regulator into a package measuring just 6.25mm square and 1.8 mm high. The complete LTM4623 circuit only requires one input capacitor and one output capacitor, a resistor to set Vout and a small capacitor for Vout tracking and soft-start. At just 1.8mm height the regulator can be mounted on the PCB reverse side.
LTM4623 – Ultrathin 20VIN, 3A Step-Down DC/DC μModule Regulator - [Link]
By Steven Keeping @ digikey.com:
Switching DC-DC voltage converters (“switching regulators”) offer some key advantages over linear regulators. Chief among these are efficiency and flexibility; switching regulators can step-up (boost), step-down (buck), and invert voltages with ease. Contemporary modular chips are compact, reliable, and available from multiple suppliers (see the TechZone article “Understanding the Advantages and Disadvantages of Linear Regulators” for a full comparison between switching and linear regulators).
However, this flexibility comes at the expense of increased complexity. For an engineer familiar with the elegance of a linear regulator, designing a power supply based around a switching device can be a little daunting. The key to overcoming the challenge is an understanding of what is going on inside that little black chip.
The Difference Between Switching Regulator Continuous and Discontinuous Modes - [Link]
by Susan Nordyk @ edn.com
Based on a four-switch single-inductor architecture, the LT3790 synchronous buck-boost DC/DC controller from Linear Technology accommodates an input of 4.7 V to 60 V and delivers up to 250 W of continuous power for use in a variety of automotive and industrial applications. The device operates from input voltages above, below, or equal to the output voltage, making it well-suited for automotive designs where the input voltage can vary dramatically during stop/start, cold crank, and load dump.
LT3790 – 60V Synchronous 4-Switch Buck-Boost Controller - [Link]
by Haifeng Fan @ edn.com:
Isolated DC/DC converters are required in a broad range of applications including power metering, industrial programmable logic controllers (PLCs), insulated-gate bipolar transistor (IGBT) driver power supplies, industrial fieldbus, and industrial automation. These converters often are used to provide galvanic isolation, improve safety, and enhance noise immunity. Moreover, they can be used to generate multiple output voltage rails including dual-polarity rails.
Understanding isolated DC/DC converter voltage regulation - [Link]
The NXP Flyback SMPS Design Tool helps you design flyback power supplies using NXPs TEA1721, TEA1723, TEA1733 and TEA1738 family. The TEA1721(A, B, D, F) family, the TEA1723(A, B, D, F) family, the TEA1733(A, B, C, M, L) family and TEA1738(F, G, L) family are low cost Switched Mode Power Supply (SMPS) controller IC’s intended for flyback topologies.
The latest update of the tool combines the TEA172x family and the TEA173x family into one tool. It comes along with a new style and an improved flow. Now it is also possible to export all design parameters, results and graphs automatically into an Excel sheet for post-processing or presentation purposes. Furthermore the database of transformer cores is extended.
Flyback SMPS Design Tool - [Link]