Page 12 - EngineerIT July 2022

ELECTRONICS

How Monolithic Driver + MOSFET

(DrMOS) technology improves

power system design

By Christian Cruz, Senior Applications Development Engineer, Joseph Rommel Viernes, Power Applications Staff Engineer,
Kareem Atout, Senior Systems Engineer, Gary Sapia, Team Leader, and Marvin Neil Cabuenas, Senior Firmware Engineer

his article describes the latest known as smart power stages, increased package. Together with a suitable PWM
driver plus MOSFET (DrMOS) steadily and power-switching technologies controller, this smart power stage
Ttechnology and its advantages continued to advance, Analog Devices provides the industry’s highest efficiency,
in voltage regulator module (VRM) came up with its version of DrMOS smart lowest noise, and highest density power
applications. Monolithic DrMOS devices power modules. The LTC705x DrMOS conversion available to the market.
enable power systems to improve greatly series makes use of ADI’s patented Silent This combination equips a high current
in terms of power density, efficiency and Switcher® 2 architecture, along with an voltage regulator module with the latest
thermal performance, which in turn can integrated bootstrap circuitry, which techniques on efficiency and transient
enhance the overall performance of end allow the DrMOS module to switch at an response. The typical application of
applications. ultrafast speed with reduced power losses LTC7051 is illustrated in Figure 1. It
and switch-node voltage overshoot for
Introduction improved performance. LTC705x DrMOS To demonstrate the key features of
Through the advancement of technology, devices also offer safety features such as LTC7051, ADI created an evaluation
microprocessors have become denser overtemperature protection (OTP), input board to showcase the performance of
and faster on a horizontal scale thanks overvoltage protection (V IN OVP), and the LTC7051 vs. a product available from
to the multicore architecture. Thus, the undervoltage lockout (UVLO) protection. the competition. Such a demonstration
corresponding power required by these platform facilitates an unbiased,
devices has increased drastically. Such LTC7051 SilentMOS Smart Power accurate way of comparing essential
power for microprocessors is provided by a Stage parameters such as efficiency, power
voltage regulator module (VRM). The LTC7051, a member of the LTC705x loss, telemetry accuracy, thermal, and
electrical performance of LTC7051 DrMOS
There are two main parameters driving DrMOS family, is a 140 A monolithic with those of a competitive product.
the development of voltage regulators in smart power module that successfully The objective of the comparison was
this field. First is the power density (power combines high speed drivers with high to remove any doubt on the validity of
over unit volume) of the voltage regulator, figure of merit (FOM) top and bottom the outcome. The said demonstration
which must be increased sharply to meet power MOSFETs and a comprehensive platform was used to highlight best-
the high-power requirement of the system monitoring and protection circuitry in in-class DrMOS performance metrics
in a limited volume of space. The other one electrically and thermally optimised regardless of the manufacturer.
parameter is power conversion efficiency
for reduced power losses and better
thermal management.
As developmental challenges continue
to evolve, the power industry will find
ways of satisfying the consequential
requirements. One solution incorporates
an advanced switching MOSFET, which is a
major building block of voltage regulators,
and its corresponding driver in a single,
monolithic die along with advanced
packaging, enabling compact and efficient
power conversion. These DrMOS power
stages have optimised, high speed power
conversion.
As the demand for these power stages, Figure 1. Dual-phase POL converter.

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