{"id":4512,"date":"2022-04-27T09:14:03","date_gmt":"2022-04-27T09:14:03","guid":{"rendered":"https:\/\/auto-talks.com\/?p=4512"},"modified":"2023-02-26T06:32:41","modified_gmt":"2023-02-26T06:32:41","slug":"when-v2x-gets-too-hot","status":"publish","type":"post","link":"https:\/\/auto-talks.com\/zh\/when-v2x-gets-too-hot\/","title":{"rendered":"When V2X gets too hot"},"content":{"rendered":"<p><em>By Onn Haran<\/em><\/p>\n\n\n\n<p>In order for a<a href=\"https:\/\/auto-talks.com\/zh\/\"> Vehicle-to-Vehicle Communication<\/a> (V2X) sensor to detect a car behind the corner, it should work reliably. One of the unique requirements of the Automotive market is the high operating temperature. While a typical consumer product is graded for 70\u1d52 ambient temperature operation, the lowest Automotive-grade (AEC-Q100 grade 3) should operate at 85\u1d52. The requirement is raised to 105\u1d52 (AEC-Q100 grade 2) when the electronic unit is placed above the roof, at the antenna, or below it, at the headliner.<\/p>\n\n\n\n<p>Vehicles should operate on the hottest summer days with minimal wind flow and no shade. A dark color roof can reach very high temperatures when the vehicle is parked in the sun, or slowly progressing in a traffic jam. A chip not designed to work at high temperatures will suffer reliability degradation, shortening its lifetime. For this reason, all carmakers take temperature requirements very seriously.<\/p>\n\n\n\n<p>A V2X subsystem includes multiple building blocks: radio, modem, security signing (HSM) and verification, and a high-capacity CPU for processing. All these blocks should operate at high temperatures. When a system is composed of multiple chips, the chip with the lowest operating temperatures sets the V2X limit of operation.&nbsp;<\/p>\n\n\n\n<p>Multiple methods can be considered in order to increase a system\u2019s operating temperature:<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li><strong>Thermal efficient package<\/strong>: One possible solution is embedding a metal slug in the package, at the expense of a <strong>cost increase<\/strong>.<\/li><li><strong>Larger packaging<\/strong>: Increasing package size cannot realistically be considered due to the size constraints, particularly in the case of TCU or antenna installation. Larger packaging also increases the cost.<\/li><li><strong>Thermal management<\/strong>: A heat sink improves thermal dissipation while complicating the mechanical design and <strong>increasing cost<\/strong>. When a heat sink isn\u2019t enough, a fan is required. The cost impact is significantly higher and a single point of failure is introduced. This point of failure is troubling considering the contribution of <a href=\"https:\/\/auto-talks.com\/zh\/technology\/functional-safety-for-v2x\/\">V2X to vehicle safety<\/a>, which will increase in the upcoming years.<\/li><li><strong>Low-duty cycle operation<\/strong>: Wireless standards commonly reduce the operation cycle by limiting the communication to specific slots. For example, cellular communication applies Discontinuous Reception (DRX) turning off the receiver for a couple of seconds while communication is idle. This <strong>isn\u2019t applicable<\/strong> to V2X. A safety-critical message can arrive at any given moment, and the receiver should be ready with minimal latency. In addition, in C-V2X, the channel should be constantly scanned to determine the transmitter resource allocation.<\/li><li><strong>Specifically designed for high-temperature<\/strong>: This involves a silicon process with high junction temperature and applying low-power design techniques. The chip should be simulated and tested at high temperature and voltage corners.<\/li><\/ul>\n\n\n\n<p>The first three methods (thermal efficient package, enlarged packaging and thermal management) incur a cost penalty. The fourth method (low-duty cycle operation) is not applicable. That leaves the fifth method (high-temperature thermal design) as the only robust and cost-efficient solution. Tier1s do not need to increase the design cost, risk, and complexity by adding thermal management.<\/p>\n\n\n\n<p>A chip designed as a consumer cellular modem and used for V2X without being specifically designed for high-temperature operation will be at a high risk of failing temperature requirements in a real operating environment.<\/p>\n\n\n\n<p><a href=\"https:\/\/auto-talks.com\/zh\/products\/\">Autotalks chipsets<\/a> are rigorously designed for high operating temperatures. They can be used in an antenna or headliner without any thermal management. The high-integration level assures that all building blocks, radio, modem, security and processing can sustain a sunny day in the desert in a black car.<\/p>","protected":false},"excerpt":{"rendered":"<p>By Onn Haran In order for a Vehicle-to-Vehicle Communication (V2X) sensor to detect a car behind the corner, it should work reliably. One of the unique requirements of the Automotive market is the high operating temperature. While a typical consumer product is graded for 70\u1d52 ambient temperature operation, the lowest Automotive-grade (AEC-Q100 grade 3) should &hellip;<\/p>\n<p class=\"read-more\"> <a class=\"\" href=\"https:\/\/auto-talks.com\/zh\/when-v2x-gets-too-hot\/\"> <span class=\"screen-reader-text\">When V2X gets too hot<\/span> \u67e5\u770b\u5168\u6587 &raquo;<\/a><\/p>","protected":false},"author":1,"featured_media":4515,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_eb_attr":"","footnotes":""},"categories":[9],"tags":[],"class_list":["post-4512","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/auto-talks.com\/zh\/wp-json\/wp\/v2\/posts\/4512","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/auto-talks.com\/zh\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/auto-talks.com\/zh\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/auto-talks.com\/zh\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/auto-talks.com\/zh\/wp-json\/wp\/v2\/comments?post=4512"}],"version-history":[{"count":3,"href":"https:\/\/auto-talks.com\/zh\/wp-json\/wp\/v2\/posts\/4512\/revisions"}],"predecessor-version":[{"id":4648,"href":"https:\/\/auto-talks.com\/zh\/wp-json\/wp\/v2\/posts\/4512\/revisions\/4648"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/auto-talks.com\/zh\/wp-json\/wp\/v2\/media\/4515"}],"wp:attachment":[{"href":"https:\/\/auto-talks.com\/zh\/wp-json\/wp\/v2\/media?parent=4512"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/auto-talks.com\/zh\/wp-json\/wp\/v2\/categories?post=4512"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/auto-talks.com\/zh\/wp-json\/wp\/v2\/tags?post=4512"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}