What is MCPCB
In recent times, the utilization of LED products has surged in popularity, leading to a corresponding rise in the prominence of MCPCB - Metal Core Printed Circuit Boards. This trend has found favor not only within the lighting and automotive sectors but also resonates with consumers at large. This newfound affinity is largely attributed to the economic appeal of LED lights, which bear a mere fifth of the cost of incandescent counterparts. Furthermore, CFL, while competing on efficiency, come up short on cost-effectiveness and the capacity to contend with the compact brilliance of minuscule LED. This prevailing shift has led to LED taking center stage as a pivotal design element in numerous devices. However, amidst this illuminating transformation, a crucial facet of LED operation demands unwavering attention within the realm of product design: the relentless issue of heat management.
What exactly is MCPCB?
MCPCB, also referred to as a metal substrate PCB or thermally conductive PCB, presents a distinctive circuit board type where the underlying material comprises metal, specifically intended to address the thermal dissipation needs of the circuitry. The robust metal layer, typically copper or aluminum, consistently envelops one facet of the PCB. The positioning of this metal core can vary, either centralized, interstitial, or situated at the rear of the MCPCB board.
At its core, the MCPCB serves the primary function of efficiently channeling heat away from critical components on the board, extending its influence to encompass less pivotal areas, including the metal core itself. These MCPCB base metals often offer alternative choices in relation to CEM3 or FR4 boards. MCPCB thickness and material
The metal core within a thermally conductive PCB showcases diversity through materials such as aluminum, copper, or a fusion of specialized alloys. Specifically, aluminum-based variants are referred to as aluminum core PCB, representing the prevalent choice. Conversely, copper-oriented iterations are known as heavy copper PCB or copper core PCB. While occasional demands for materials like steel or brass may arise, they tend to be cautioned against due to their limited suitability. The innate hardness of metal PCB materials poses challenges when dividing these PCB into smaller segments. Selecting the optimal metal PCB material involves additional considerations, encompassing the compatibility of the chosen metal with the manufacturing process and any potential reactivity with associated chemicals.
Typically, the metal core thickness within a PCB substrate ranges from 30 mil to 1.25 mil. Nevertheless, deviations toward thinner or thicker dimensions remain feasible. MCPCB exhibit a copper foil thickness spanning from 1 to 10 oz, further underscoring their versatile capabilities.
Advantages of MCPCB
When it comes to LEDs, they often follow the standard protocol for mounting and connection on a circuit board, much like any other component. For simpler scenarios involving just a few LEDs, such as the red and green variants, there's little need to deviate from conventional PCB layout practices. Nevertheless, the landscape shifts when dealing with comprehensive lighting solutions that integrate arrays or rows of MCPCB LEDs, and this trend is poised to persist.
Safeguarding these devices against premature failure and potential safety risks necessitates effective cooling measures. Optimal cooling not only preserves longevity but also maintains consistent light emission. Transitioning from a standard FR4 PCB to an MCPCB configuration stands as a viable consideration in this regard.
Metal core PCBs offer a slew of advantages, primarily harnessing distinct substrate materials purpose-built to enhance design reliability, and they operate efficiently at elevated temperatures. These substrates not only serve as a secure mount for components but also excel at proficiently channeling and dissipating heat. By orchestrating heat transfer away from the thermal operational region of components through the layered construct of the MCPCB, these substrates effectively tackle heat dissipation.
The veracity of MCPCB shines through as an ingenious remedy to address the thermal challenges posed by PCBs integrating a substantial number of LEDs.
MCPCB vs Standard Epoxy Glass Board
A crucial distinction to grasp between MCPCBs and regular PCBs lies in their collaborative material composition, working harmoniously to achieve desired outcomes. In the realm of MCPCB LEDs, a copper circuit layer becomes intertwined and interconnected with a thermally conductive dielectric material.
The thermal conductivity of dielectric substances is quantified in W/mK (watts per meter, Kelvin). Ratings around 2.0W are commonplace, with such materials typically showcasing thermal conductivity six to seven times that of FR4.
The optimal approach is to maintain a thin dielectric layer, thereby establishing the shortest feasible path from the heat source to the metal backplane – an entity boasting notably higher thermal conductivity compared to dielectric counterparts. Varieties of materials are often available in diverse thicknesses, typically spanning the range of 0.003 to 0.006 inches. It's advisable to abstain from specifying thicker materials, which could compromise the material's efficacy in executing its thermal transfer function.
The foundation, represented by the bottommost backplate, stands as the most substantial component within this architecture. Diverse thickness options are available for this element, yet the recommendation leans toward the usage of common types like 3.2mm, 1.5mm, and 1.0mm. These selections offer the advantages of ready availability and timely procurement, ensuring streamlined operations. Moreover, the metal layer inherent in this backplate ensures flatness, bolsters rigidity, and contributes sufficient thickness. This strategic design choice facilitates compatibility with mounting hardware deployed for standard-thickness boards. Notably, the metal plate section of the board remains devoid of solder mask or surface treatment.