Use DS3882 CCFL controller to drive the common circuit of two lights

This application note describes a backlight LCD application in which two adjacent CCFL lamps share a common, low-voltage side lamp connection. This design is found in automotive, industrial, and avionic applications. The article describes how a DS3882 CCFL controller can be used to drive the two CCFL lamps that share a common return.

PoE+ circuits provide 13W to 70W power to powered devices (PDs)

This application note presents a simple, cost-effective, pre-IEEE® 802.3at PoE+ Powered Decice (PD) solution that employs the MAX5941B. The preliminary requirements of PoE+ PDs are discussed, as is the advantage of extending the existing MAX5941B circuit to implement a PoE+ PD. Test results including inrush-current limit, efficiency, output ripple, and dynamic response are presented for a 3.3V, 30W PD.

Power consumption (PD) module reference design based on MAX5941B PWM controller

This application note provides a reference design for an IEEE® 802.3af-compliant, 12.95W adjustable-output powered-device module. Assembled on a 12cm² PCB, the module is based on the MAX5941B PWM controller and includes hot-swap power switching, a DC-DC converter, and a pair of ORing diode bridges for compatibility with an external 12V adapter. This article details the performance of the module and provides a schematic, PCB layout, and components list for the design.

Telecom hot-swap reference design effectively solves the problem of instantaneous input overvoltage and power outage

This 80W telecom hot-swap reference design is immune to 150V input-voltage transients and 16ms power dropouts. Additional features include -32V to -72V operation, two-diode OR-ing input, and an inrush current that is ≤ 1.5 times the full -load current. Included are a detailed schematic, representative PCB layout, bill of materials, waveforms detailing actual performance at startup, -150V input transient, and full-load holdup at power loss.

Design a car cold start boost circuit using the MAX15005 current mode controller

This reference design shows how to use a MAX15005 automotive power-supply controller as a boost circuit to maintain a constant voltage during an automotive cold-crank condition.

MR-16 LED driver and 5V auxiliary supply for powering pulsed LED coolers

This application note presents a reference design for a 4S1P MR-16 LED driver that provides 750mA to a string of four white LEDs (WLEDs). The circuit operates from a 24V source and is based around the MAX16820 hysteretic LED driver. Also included is a MAX5033 24V-to-5V, 150mA switching power supply to power a Nuventix® pulsating LED cooler.

Reference design to ensure dynamic output voltage of printhead power supply

This article describes some important design parameters for managing power in a printer. The reference design shows how to use a MAX15005 power-supply controller as a SEPIC circuit to obtain a high-variable output voltage for a print-head power supply. The circuit schematics , bill of materials (BOM), test measurements, and results are provided.

Vacuum Tube Fluorescent Display (VFD) Reference Design in Automotive

This article describes a vacuum fluorescent display (VFD) and some ideal applications for the technology. The reference design then shows how to use a MAX15005 power-supply controller in a flyback topology to obtain multiple output voltages for a vacuum fluorescent display.

Avalanche Photodiode (APD) Bias Supply and Current Monitoring

This reference design presents a circuit for addressing the power-supply and current-monitoring requirements of APD biasing applications. Based on the MAX15031 DC-DC converter, the application circuit provides a 70V, 4mA, DC-DC power converter with a 2.7V to 11V input supply-voltage range.

Ultralow Quiescent Current Linear Regulator for Automotive Air Bags

This reference design shows how to increase the output current of the MAX15006/MAX15007 linear regulators to meet the power-supply requirements for an automotive air bag.

A reference design for building an auxiliary power supply for an LCD TV or set-top box using the MAX15026

This application note shows a reference design using the MAX15026 low-cost, high-efficiency synchronous buck converter in an auxiliary power supply for LCD TVs or set-top boxes. This reference design generates a 5V, 5A power supply from a wide, 6.5V to 24V input voltage range.

Use MAX5060 to design a high-current power supply with lossless current detection

This reference design shows how to use a MAX5060 current-mode, step-down power-supply controller to implement lossless current sensing for high-current applications. In this design, the series resistance (DCR) of the inductor is used for current sensing to avoid power loss in the current-sense resistor.

3S3P Automotive Tail Light (RCL) LED Driver Reference Design

This application note presents a reference design for a rear combination lamp (RCL) LED driver in a 3-series, 3-parallel (3S3P) configuration. Using the MAX16823 linear driver and external BJTs, this design provides 200mA per string as well as enhanced heat dissipation. Also included is PWM dimming circuitry for tail-light inputs and full brightness for brake-light inputs. Double-battery and load-dump conditions have been taken into consideration.

Offline LED Driver Reference Design

This application note presents a reference design for a nonisolated LED driver intended to operate directly from a 400V _DC input. The design drives a string of 27 WLEDs (white LEDs) or, optionally, 6 amber LEDs at 400mA. The topology is a discontinuous flyback with a transformer. The MAX16801 HB (high brightness) LED controller is featured.

5S2P AR111 LED light driver reference design

This application note presents a reference design for an AR111 lamp LED driver with two parallel strings of five LEDs (5S2P). Using the MAX16819 in buck-boost mode, the circuit operates from 12VAC and delivers an average current of 500mA per string.

LED backlight SEPIC driver

This is a reference design for a SEPIC/linear LED-display backlight driver for eight parallel strings of 8 WLEDs (white LEDs) at 70mA/string. The dimming ratio is 4000:1. The input voltage is 16V to 36V with 50V transients. The design combines a SEPIC switching power supply with adaptive feedback and linear current sinks for high dimming ratios. The MAX16809 16-channel LED driver is featured.

Portable Projector 6A RGB LED Driver Reference Design

This reference design for a 6A step-down LED driver is based on the MAX16821 device. This circuit drives a single LED. This design includes the circuit specifications, circuit schematic, and circuit description and performance.

LED signal light driver reference design

This application note presents a reference design for a signal-lamp linear LED driver that consists of six strings of 4 LEDs per string and delivers 350mA per string with a common cathode configuration. Common cathode arrangements require that the current-sense resistors be placed on the high (anode) side, which forces the LED drivers to use a level shifter.

LED backlight BOOST driver

This is a reference design for an LED display-backlight driver. The design uses a boost power supply with adaptive feedback for efficiency and linear current sinks for a high dimming ratio (2000:1). The input voltage is 8V to 18V with 50V transients, and the load is three parallel strings of 8 LEDs (34V) at 150mA/string. The MAX16809 16-channel LED driver is featured.

Designing a buck-boost LED driver using the MAX16834

This reference design is for a buck-boost LED driver. The MAX16834 current-mode high-brightness LED driver is featured, and the MAX16834 EV (evaluation) kit is used to implement the design. The application note shows the design specifications, schematic, bill of materials (BOM), and performance data.