Take the Mystery Out of the Switched-Capacitor Filter: The System Designer's Filter Compendium:  AN40 - Linear Technology - This note presents guidelines for circuits utilizing LTC's switched capacitor filters. The discussion focuses on how to optimize filter performance by optimizing the printed wiring board, the power supply, and the output buffering of the filter. Many additional topics are discussed such as how to select the proper filter response for the application and how to characterize a filter's THD for DSP applications.

Tandem hookups Enhance utility of DC/DC units:  01/02/97 EDN-Design Ideas / (added 02/05)  Designers whose applications demand increased power or nonstandard voltages have traditionally needed to use custom supplies or to compromise in the areas of component cost or pc-board space. However, the flexibility you can gain by connecting isolated, compact dc/dc converters in parallel or series allows low-cost, standard parts to meet system needs with minimal cost and space penalties. As Figure 1 shows, you can use multiple dc/dc converters to generate nonstandard positive- and negative-voltage rails by simply connecting the devices in series, with the positive output of one converter connecting to the negative input of another....

TB065: Linear Circuit Devices for Applications in Battery Powered Wireless Systems:  Microchip Application Note - Published 24-Feb-03   (app note added 6/06)

TB065a: Linear Circuit Devices for Applications in Battery Powered Wireless Systems:  Microchip Application Note - Published 20-Oct-04   (app note added 6/06)

Testing inductors at application frequencies:  Coilcraft - Power Magnetics Application Note - (app note added 6/06)

Testing LCD Backlight Inverters using the Agilent N6700 Modular Power System (MPS):  Agilent Application Note   (app note added 6/06)

The 3G Power Game: Quiescent Current and Intelligent Biasing:  MicroNote 709 from Microsem  (app note added 6/06)

Three Input Supply Powers 3.3 Volt Portables:  The single-ended primary-inductance converter (SEPIC) of Figure 1 accepts input voltages ranging from 3V to over 6V, and produces a regulated 3.3V, 200mA output. It accepts an input voltage from three sources: a 5V dc wall cube, a 3-cell AA battery, and a lithium backup battery. Maxim Application Note 136  (app note added 2/06)

Transformer Buys Lower Shutdown Current:  11/23/94 EDN-Design Ideas / (added 3/03) The step-up dc/dc converter in Fig 1 trades a slight loss in efficiency and a transformer in place of a less expensive inductor for two important advantages: The inductor offers low shutdown current because the transformer eliminates a leakage path. The circuit stays in regulation, even if the input voltage rises above its nominal figure. Note that in Fig 1, the input voltage is negative with respect to the output's ground. Transistor Q1 shifts the output voltage's level down to a level compatible with IC1's feedback pin...  

Transformer Design Consideration for off-line Flyback Converters Using Fairchild Power Switch (FPStm) / AN-4140:  Fairchild Application Notes / (app note added 6/06)

Transformerless DC/DC converter produces Bipolar outputs:  04/29/04 EDN Design Ideas  /  (added 1/05)  The conventional way to produce dual (positive and negative) outputs from a single positive input is to use a transformer. Although such designs are relatively simple, the transformer inherently introduces the problem of size. It can be challenging to fit a transformer into an application in which it's important to minimize the circuit footprint and height....

Transformerless Power Supplies: Resistive and Capacitive:  Microchip Application Note - Published 22-Sep-04   (app note added 2/06)

Transformerless Supply Fits CATV Applications:  05/22/97 EDN-Design Ideas / (added 3/03) Coaxial CATV systems derive their power from a 60-Hz square wave that shares the center conductor with the television channels. You often need to place active devices along the distribution path. If the dc-power requirements for these devices are small, you can use a transformerless power supply to provide power to the active devices. The circuit in Figure 1 provides current as high as 10 mA at 5V dc. You can modify the component values for any desired output voltage and current. The design equations for selecting the components are the input parameters,....  

Transistor Pair Lowers PWM IC's Start up Current:  03/18/99 EDN-Design Ideas / (added 6/03) An auxiliary winding usually provides power for the popular UC384X-based offline switch-mode power supplies (SMPSs). This winding feeds the main PWM controller during steady-state operation. However, the controller always needs a small start-up current, which clearly plagues the efficiency in very low-power standby SMPSs with POUT =500 mW, for example. Any wasted source power, such as for the start-up network and controller supply, adds to the power drawn from the mains and significantly degrades the overall efficiency. Obtaining an acceptable efficiency at high line voltage represents a tough design task. Some tricks totally stop the start-up current by using a high-voltage bipolar or MOSFET (Reference 1). However, the....

Transistors tame perfidious leakage inductance:  09/27/01 EDN Design Ideas  /  (added 1/05)  In flyback converters that use primary regulation, the loose coupling between the power secondary and the primary auxiliary windings often results in poor cross-regulation. This situation arises mainly from the leakage inductance but also comes from the level of the primary clamp voltage. Figure 1 shows a typical application schematic using On Semiconductor's (www. ...

Turn Off Snubber Design for High Frequency Modules:  Turn-off snubbers are passive circuits made of diodes, resistors and capacitors dedicated to storing energy for a short period to: Decrease switch power losses during turnoff and Modify switching I-V diagram to fit safely within the switching safe operating area Application Note Microsemi APT0404 ( app note added 4/08)

Two Channel Gate Driver for Large IGBT Modules:  The BG2A is a fully isolated two channel gate drive circuit designed for use with dual IGBT modules. The BG2A utilizes Powerex VLA500-01 or VLA502-01 hybrid gate drivers to provide efficient switching of modules rated up to 1400A. The hybrid gate driver features a built-in high speed opto-coupler, short circuit protection and an isolated DC to DC converter with 2500VRMS isolation. (added 3/05)

UCC3809 Evaluation Module:  The UCC3809EVM evaluation module is an isolated 10-W, 3.3-V converter designed for telecom input voltages, nominally -48 Vdc, but ranging from -32 Vdc to -75 Vdc. The UCC3809 economy primary-side controller is used as the pulse-width modulator (PWM), combined with a TLV431 low-voltage adjustable-precision shunt regulator on the secondary side. The nominal switching frequency for this converter is approximately 400 kHz. The UCC3809 is configured with a 50% duty-cycle clamp.  (added 3/05)

Ultra-Low Power High Efficiency DC/DC Converter Operates Outside the Audio Band:  DN86 -  Design Notes (Linear Technology) (app note added 1/06)

UltraLow Quiescent Current DC/DC Converters for Light Load Applications:  DN142 -  Design Notes (Linear Technology) (app note added 2/06)

Understanding Power Splitters  AN-10-006:  Application Note - MiniCircuits.com  (app note added 6/06)

Understanding The Differences between Standard MOSFETs and Avalanche Energy Rated MOSFETs:  Application Note Microsemi-formerly Advanced Power Technology APT9402 ( app note added 4/08)

Unique High Efficiency 12V Converter Operates with Inputs from 6V to 28V:  DN233 -  Design Notes (Linear Technology) (app note added 1/06)

Universal Balancing Techniques:  National Semiconductor - Application Note   (app note added 2/06)

Universal DC-to-DC Converter:  (Circuit / schematic design added 6/06)

Universal High Resistance Voltmeter:  (Electronic Circuit / Schematic added 10/04)

Use a 555 timer as a Switch mode Power Supply:  11/14/02 EDN Design Ideas  /  (added 1/05)  Most switch-mode power supplies rely on a PWM (pulse-width-modulated) output that is controlled via voltage feedback. A 555-timer IC can inexpensively perform PWM. The circuit in Figure 1 shows how to turn a 555 PWM circuit into an switch-mode power supply with only one simple equation. The design uses two 555s....

Use the Built-In Measurement Capability of Power Sources and Loads:  Agilent Application Note   (app note added 6/06)

Use the LM158/LM258/LM358 Dual Single Supply OpAmp :  National Semiconductor Application Note 14 May2001 (app note added 7/02)

Using NTC Temperature Sensors Integrated Into Power Modules:  Application Note - Advanved Power Technology - APT0406  (app note added 6/06)

VDS(On) VCE(Sat)Measurement:  Application Note - Advanved Power Technology - APT0407  (app note added 6/06)

Wallcube DC/DC Converter is 85% Efficient:  09/12/97 EDN-Design Ideas / (added 3/03)   -- Ubiquitous12V wall cube generates an unregulated dc voltage of 8 to18V, depending on line voltage and load, this circuit generates a regulated5V400 mA from it very efficiently

World’s First Dual 12-Bit DACs in SO-8 (LTC1446/LTC1446L):  DN131 -  Design Notes (Linear Technology) (app note added 1/06)

ZXSC100 Single cell DC-DC converter LED driving applications:  Zetec Semiconductors  - Applications Notes - ZXSC100 single cell DC-DC converter offers an ideal solution to driving white LEDs in flashlights, enabling operation from a single NiCd or NiMH cell.   (app note added 2/06)