FPGA Power Solutions

Complete power solution for FPGAs

Buck Regulator Current Limiting Circuit

This article demonstrates how to achieve current limit for the MAX1692 PWM step-down regulator by using a MAX4173H current-sense amplifier.

Portable devices require high-performance battery chargers

Three techniques for charging lithium-ion (Li+) batteries are described. Linear, switch-mode, and constant-current pulse circuits are shown for each charging method.

Single Cell Li+ Cradle Charger with Linear AC Adapter

The single cell Lithium-ion (Li-ion) battery charger that does not dissipate power (no heat) can also use a low cost linear AC adapter. This application note discusses how to design a simple and low-cost Li-ion charger.

Isolated power supplies for telecom applications

Simple easy to use high side current sense amps protects power supplies as a result of irregular supply voltage caused by short-circuit conditions.

Provides +5V and +3.3V power to portable devices from USB port

A portable device using the circuit of Figure 1 derives power from the USB bus. The MAX1811 uses USB power charges a lithium-ion (Li+) battery at, USB compatible, 100mA or 500mA rates. Battery power is then stepped up with the MAX1797 to create the 5V supply rail. The 5V supply rail is then stepped down with the MAX1837 to create the 3.3V supply rail. The circuit includes a low battery shutdown to protect the Li+ battery and offers a convenient charging LED.

Driving LEDs in Battery-Powered Applications: Efficiently Control Brightness Power

White light-emitting diode (WLED) drivers provide high efficiency and brightness matching for LCD backlighting in displays. To control brightness, these drivers regulate current going into LEDs that are arranged in either serial or parallel configuration. Charge pumps drive parallel LEDs whose currents are regulated with individual regulators or simple ballast resistors. Inductor-based converters deliver current to a string of LEDs, inherently equal. Both configurations aim to drive LEDs efficiently for cell phones, PDAs, and digital still cameras.

Flexible system fault protection circuit 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.

Step-down/inverting 3A, ±5V power supply with all-ceramic capacitor design

A MAX8538 dual synchronous buck controller supplies both +5V and -5V outputs at 3A. One controller operates as a synchronous rectified step-down (buck) converter while the second controller runs a transformer driven inverter. The circuit also features soft start and soft stop .

Power supplies that meet AMD K8 low-power mobile processor specifications

This application note describes a two-phase, synchronous, step-down converter that is fully compliant with the AMD® K8 Low-Power Mobile Specification. It includes details of the circuit operation, schematic, bill of materials, and a 1.2 volt, 27.3 Amp reference design with test data.

Charge battery via USB

Many devices with rechargeable batteries use USB power to recharge the batteries while they are connected. This application note describes the power available from USB and how it can be used to charge batteries, including circuits and some hints.

Provides three-channel, ±5% stable output high-efficiency PoE (Power over Ethernet) power supply

This note describes a triple-output, high efficiency, POE (Power over Ethernet) power supply with synchronous rectification. The supply has ±5% regulation an all outputs and meets all the IEEE802.3af requirements. The topology for the dc-dc converter is a continuous current flyback. The switching frequency for the primary PWM is 275 Khz.

IEEE 802.3af compliant single-port, powered device applications

Power-over-Ethernet (PoE) technology enables power-sourcing equipment (PSE, a switch/router or midspan system) to deliver up to 15W of power to IEEE® 802.3af-compliant powered devices like IP phones and wireless LAN access points. This application note describes how to design a single-port PSE system to meet the IEEE 802.3af signature, classification, and power-management requirements. The single-port PSE in this example is designed using the MAX5922A IC.

Designing a non-isolated flyback LED driver

Single NiMH battery simulates the circuit of a lithium battery

This circuit uses a NiMH cell to replace a lithium battery. Its output simulates the discharge characteristic of a lithium (Li+) battery.

UL certified IEEE 1394 standard single/dual port FireWire protection circuit

This application note describes Maxim's UL® Recognized, IEEE® 1394™, single- and dual-port FireWire® protective circuits. The single-port FireWire protective circuit is designed using the MAX5943A, while the dual-port FireWire protective circuit utilizes the MAX5944. To assist designers with implementing these circuits, this application note details the schematics, PCB layout, and bill of materials for each UL Recognized circuit.

Replace inefficient MR16 halogen lamps with LEDs

Replacing halogen lamps with LEDs in MR16 light fixtures can save substantial energy while reducing electricity and maintenance costs. This application note details the advantages of using LEDs in MR16 fixtures, and it presents an LED driver circuit that enables a 5W white LED with integrated heatsink to replace a 10W halogen bulb in MR16 lamps.

Using MAX15005 for power supply and driving of LED application systems

This reference design is a complete application design for an automotive LED application. It utilizes the MAX15005 current-mode controller to boost a standard lead-acid car battery to 21V for driving a string of automotive LEDs.

MAX5066 Reference Design for High-Performance Systems

The MAX5066 high performance dual buck regulator provides outstanding performance. The reference design in this application note depicts a detailed solution with complete schematic, bill of materials, and load-transient-response scope photos.

MAX5073 Dual Buck Converter Reference Design Operating at 2MHz Switching Frequency

The MAX5073 is a dual converter capable of operating as a buck or boost converter. As a dual buck converter, this device can deliver up to 2A and 1A of output current. The reference design focuses on the MAX5073 operating as a buck converter with a switching frequency of 2MHz, which allows the use of smaller passive components and keeps it out of the AM band for automotive applications.