ОПИСАНИЕ

The LTM4671 is a quad DC/DC step-down μModule (micromodule) regulator offering dual 12A and dual 5A output. Included in the package are the switching controllers, power FETs, inductors and support components.Operating over an input voltage range of 3.1V to 20V, the LTM4671 supports an output voltage range of 0.6V to

3.3V for two 12A channels and 0.6V to 5.5V for two 5A channels, each set by a single external resistor. Only bulk input and output capacitors are needed.

Fault protection features include overvoltage, overcurrent and overtemperature protection. The LTM4671 is offered in 9.5mm × 16mm × 4.72mm BGA package.

 

ОСОБЕННОСТИ

Quad Output Step-Down μModule Regulator with Dual 12A and Dual 5A Output

Wide Input Voltage Range: 3.1V to 20V

Dual 12A DC Output from 0.6V to 3.3V

Dual 5A DC Output from 0.6V to 5.5V

Up to 7W Power Dissipation (TA = 60°C, 200LFM, No Heat Sink)

±1,5% Регулировка общего выходного напряжения

Dual Differential Sensing Amplifier

Управление в режиме тока, быстрая переходная характеристика

Возможность параллельного подключения для повышения выходного тока

Selectable Burst Mode® Operation

Отслеживание выходного напряжения

Выход внутреннего диода температурного датчика

Внешняя синхронизация частоты

Защита от перенапряжения, тока и температуры

9.5mm × 16mm × 4.72mm BGA Package

 

Приложения

Multirail Point-of-Load Regulation

Применение ПЛИС, ЦСП и ASIC

 

ОПЕРАЦИЯ

The LTM4671 is a quad output standalone non-isolated switch mode DC/DC power supply. It has built-in four separate regulator channels which can deliver 12A, 12A,5A, 5A continuous output current with few external input and output capacitors. Two 12A regulator provides precisely regulated output voltage programmable from 0.6V to 3.3V via a single external resistor over 3.1V to 20V

input voltage range while the other two 5A regulator can support output voltage from 0.6V to 5.5V. Dual true differential remote sensing amplifiers are included in the high current channels to get accurate regulation at load point.

The LTM4671 has integrated four separate constant ontime valley current mode regulators, power MOSFETs,inductors, and other supporting discrete components.

For switching noise-sensitive applications, the switching frequency can be adjusted by external resistors and the μModule can be externally synchronized to a clock..

With current mode control and internal feedback loop compensation, the LTM4671 module has sufficient stability margins and good transient performance with a wide range of output capacitors, even with all ceramic output capacitors. For Dual 12A output rails, an optional Type II C-R-C external compensation network is allowed to customize the stability and transient performance.

Current mode control provides the flexibility of paralleling any of the separate regulator channels with accurate current sharing. With a build in clock interleaving between each two regulator channels, the LTM4671 could easily

employ a 2+1+1 or 2+2 channels parallel operation which is more than flexible in a multirail POL application like FPGA. Furthermore, the LTM4671 has CLKIN and CLKOUT pins for frequency synchronization or PolyPhase multiple

devices which allow up to 8 phases of 12A or 5A channelscan be cascaded to run simultaneously.

Current mode control also provides cycle-by-cycle fast current monitoring. An internal overvoltage and undervoltage comparators pull the open-drain PGOOD output low if the output feedback voltage exits a ±10% window around the regulation point. Furthermore, in an overvoltage condition,internal top FET is turned off and bottom FET is turned on and held on until the overvoltage condition clears.

Pulling the RUN pin below 0.6V forces the controller into its shutdown state, turning off both power MOSFETs and most of the internal control circuitry. At light load currents,Burst Mode operation can be enabled to achieve higher efficiency compared to continuous mode for the dual 5A channels by setting MODE/PLLIN pin floating or tying to INTVCC. The TRACK/SS pin is used for power supply tracking and soft-start programming.

Three different temperature sensing pins are included inside the module to monitor the temperature of the module for different channels.