Due to its simplicity and low cost, the flyback converter is the preferred choice for low-to-medium isolated DC-DC power-conversion applications. However, the use of an optocoupler or an auxiliary winding on the flyback transformer for voltage feedback across the isolation barrier increases the number of components and design complexity. The MAX17690 eliminates the need for an optocoupler or auxiliary transformer winding and achieves ±5% output voltage regulation over line, load, and temperature variations.
This document describes a circuit that uses three MAX17541G buck converters and one MAX17504 step-down DC-DC converter. The circuit is arranged so that each buck converter uses the same input with four separate outputs. Each output has a different power specification. The MAX17541G regulator and features are given first, followed by the MAX17504 features.
Maxim's Power Amplifier Biasing (MAXREFDES39#) features a PA Bias circuit with the flexible Programmable Mixed Signal I/O (PIXI™) product, the MAX11300. The 2-stage amplifier design biases a 15W, LDMOS PA implemented with unprecedented simplicity, and is capable of biasing many existing PAs. Design files are available and boards are available for purchase.
The MAXREFDES1227 is a miniature 12V output isolated power supply that can deliver up to 2A load current. The design employs the MAX17596 peak-current-mode controller in discontinuous-conduction mode (DCM) flyback topology running at 125kHz. The input voltage range of MAX17596 is 4.5V to 36V; however, an extra bias winding from the transformer is used to power the controller. This allows an input operating voltage of up to 60V for this design.
When it is necessary to plug in a board into a system that is currently powered, it is critical to control the inrush current to prevent damage/system fault conditions. This application provides a simple circuit to achieve this function as well as an easy method for resetting the system and monitoring against temperature issues.
The MAXREFDES1214 is a portable USB charger that uses a lithium-ion (Li+) battery to charge a USB device from a USB Standard-A connector.
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 document details the MAXREFDES119# subsystem reference design, a 17V to 36V input, 5V output, no-opto flyback isolated power supply capable of 9W. Design files and test results are included. Hardware is available for purchase.
The MAX17595 is a peak-current-mode controller for designing wide input-voltage flyback regulators. The MAX17595 offers optimized input thresholds for universal input AC-DC converters and telecom DC-DC (36V to 72V input range) power supplies.
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.
To meet the increasing demands for isolated Power over Ethernet (PoE) power solutions, Maxim’s power supply experts have developed
The MAX17504 high-efficiency, high-voltage, synchronously rectified step-down converter with dual integrated MOSFETs operates over a 4.5V to 60V input. The converter can deliver up to 3.5A and generates output voltage from 0.9V to 90% VIN. Built -in compensation across the output voltage range eliminates the need for external components. The feedback (FB) regulation is accurate to within ±1.1% over -40°C to +125°C. The devices are available in a compact (5mm x 5mm ) TQFN lead (Pb)- free package with an exposed pad. Simulation models are available. The MAX17504 features a peak-current-mode control architecture with a MODE feature that can be used to operate the device in pulse-width modulation (PWM) , pulse-frequency modulation (PFM), or discontinuous mode (DCM) control schemes.
This document details the MAXREFDES120# subsystem reference design, a 17V to 36V input, 5V output, no-opto flyback isolated power supply capable of 12.5W. Design files and test results are included. Hardware is available for purchase.
15W 24V Offline Flyback Converter Using the MAX17595
The MAX15050 is a high-efficiency switching regulator that delivers up to 4A load current at output voltages from 0.6V to (0.9 x VIN).
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.
The MAX17574, high-efficiency, high-voltage, synchronous step-down DC-DC converter with integrated MOSFETs operates over a 4.5V to 60V input. The converter can deliver up to 3A current.
Power over Ethernet (PoE) is a technology that allows network cables to deliver power to a powered device (PD) through power-sourcing equipment (PSE) or midspan, and has many advantages over traditional methods of delivering power.
Due to its simplicity and low cost, the flyback converter is the preferred choice for low-to-medium isolated DC-DC power-conversion applications. However, the use of an optocoupler or an auxiliary winding on the flyback transformer for voltage feedback across the isolation barrier increases the number of components and design complexity.