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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
This reference design presents a circuit for using the MAX15046 step-down power-supply controller for high-input-voltage, low-output-voltage applications that require high output current.
The long strings of LEDs commonly found in TV and display backlighting, street lights, and parking garage lights require a current driver capable of producing high voltages. This reference design provides such a driver using the MAX16834, and demonstrates how very-high dimming ratios can be obtained.
This reference design uses the MAX16834 to create a high-powered LED driver for a very long string(s) of LEDs. The LED current is adjustable with a potentiometer, and can be set as high as 1.5A into as many as 20 LEDs (75V total). For long life, ceramic capacitors are used for both input and output decoupling.
This application note is an RGB LED driver reference design for a low-power projector. The design features a single MAX16821 HB LED driver to drive the RGB LEDs one at a time. This approach reduces the components needed, resulting in an efficient, small, and economical design. Board layout and test results are shown.
This LED driver reference design drives a 700mA constant current to a single string of LEDs with forward voltages up to 60V. The design allows PWM dimming based on supply chopping. The input power supply is chopped on and off at 300Hz to 1kHz frequency to achieve LED brightness control. The driver uses a fixed-frequency boost converter, controlled by the MAX16834 LED driver. This unique reference design limits the input inrush current to negligible levels without compromising either the input or output filtering. Design schematics and test results are provided.
This reference design is for a highly efficient, flyback, 12V, Class 3 powered device (PD). The design features the MAX5969B as its controller. The design also uses the MAX5974A, which controls current-mode PWM converters and provides frequency foldback for PoE applications. Using these devices, this reference design is IEEE® 802.3af/at compliant and is a high-performance, compact, and cost efficient solution for a Class 3 PD. The design can also be customized to 12V/2A Class 4 PD.
The MAX16974/MAX16975/MAX16976 high-performance DC-DC converters are standard buck controllers designed for automotive applications. This application note explains how to optimize the layout of these ICs. An example layout is provided at the end of the document.