Maxim MAX1856EUB+

Контроллер, спутниковые приставки, xDSL и кабельные модемы3 В ~ 28 В-24 В, -72 В

Overview

The MAX1856EUB offers a low-cost solution for generating a SLIC (ringer and off-hook) power supply. Using standard off-the-shelf transformers from multiple vendors, the MAX1856EUB generates various output voltages: -24V and -72V (dual output) for both ringer and off-hook supplies for voice-enabled broadband consumer premises equipment (CPE), -48V for IP phones and routers, -5V and -15V (single or dual output) for DSL CO line drivers, or negative voltages as high as -185V for MEMS bias supplies. The output voltages are adjusted with an external voltage divider. Due to its wide operating voltage range, the MAX1856EUB operates from a low-cost, unregulated DC power supply for cost-sensitive applications like xDSL, cable modems, set-top boxes, LMDS, MMDS, WLL, and FTTH CPE. The MAX1856EUB provides low audio-band noise for talk battery and a sturdy output capable of handling the ring trip conditions for ring battery. The operating frequency can be set between 100kHz and 500kHz with an external resistor in free-running mode. For noise-sensitive applications, the MAX1856's operating frequency can be synchronized to an external clock over its operating frequency range. The flyback topology allows operation close to 50% duty cycle, offering high transformer utilization, low ripple current, and less stress on input and output capacitors. Internal soft-start minimizes startup stress on the input capacitor, without any external components. The MAX1856's current-mode control scheme does not require external loop compensation. The low-side current-sense resistor provides accurate current-mode control and overcurrent protection.

Features

Applications

• GSM Base Station
• LCD-TV/PDP-TV
• Copier/Printer
• Set-Top Box
• DDR Vooo and Vπ Voltage Generation
• PC Dual Power Supply
• Server DDR Power
• Desktop Computer
• Graphics Cards
• Cell Phones