SPWG Releases v3.5 Standard

by Mark Fihn

The DisplaySearch Monitor, April 1, 2005 -  On March 29, 2005, the Standard Panels Working Group (SPWG) released v3.5 of their standard for the displays used in notebook PCs. In process since November 2004, the v3.5 document was written primarily to add a 14.x” panel at a wide aspect ratio to the SPWG standard. At this writing, several display manufacturers are known to have developed panels compliant with the SPWG v3.5 standard. Details related to the SPWG v3.5 standard are available at www.spwg.org. 

Member companies of the SPWG agreed early on that a 14.1” version at a 16:10 aspect ratio be established as the standard.  At about the same time, however, an effort was launched by display engineers at HP to standardize around a 14.0”W version (at a 15:9) aspect ratio. Although HP was first to market a 14.x”W product, the SPWG membership determined that it was not the best choice for optimization, since it differed in aspect ratio from the 12.1”W, 15.4”W, and 17.0”W products already introduced into the market. Additionally, HP’s decision to introduce a panel smaller in diagonal size than the historically well-established 14.1” (4:3) product was viewed as a problem from a marketing perspective.

HP was one of the founding companies of the SPWG, but withdrew their membership in mid-2003, apparently because HP’s display managers did not want to follow the SPWG decision to work closely with the Mobile Extended Battery Working Group (EBL-WG), which is devoted to reducing power consumption in notebook PCs. (HP is not a member of the EBL-WG.) The SPWG v3.0 and v3.5 standards are related to the integration of inverters, with guidelines that can help reduce display power consumption.  The new v3.5 standard further defines power savings opportunities in the display sub-system.

A few SPWG member companies suggested that since the HP 14.0”W panels were introduced into the market, that both the 14.0”W and 14.1”W panels should be covered by the SPWG. Most SPWG members, however, agreed that there should only be a single panel in this class of product included in the standard. Ultimately, it is widely believed that the 14.1”W version will displace the anachronistic 14.0”W panels introduced by HP.

In addition to introducing the 14.1”W panels, the new SPWG v3.5 specification introduces a new inverter connector (from JAE). The new spec also introduces a lead-free version of JST’s CCFL connector; panel power sequence T values were changed to be consistent with those in SPWG v2.0; and the inverter PWM input voltage brightness control pin was defined.

Members of the SPWG are next working on SPWG v4.0 specifications, which will address 8-bit color for displays used in notebook PCs, include displays used in Tablet PCs, identify additional performance measurement guidelines, and consider other innovations in the market.

Membership to the SPWG is free of charge and access to the SPWG standards is freely available to any interested party. Parties interested in participating in the on-going standards efforts of the SPWG are encouraged to contact one of the SPWG coordinators.

The recently formed SPWG Advisory Council was expanded by three advisors in the past weeks, including John Jacobs (currently at DisplaySearch), Carl Steudle (most recently at LG.Philips LCD), and Jessica Huang (most recently at Toppoly). The Advisory Council helps to assure that standards development process does not show undue favor any particular company, while also serving to promote the standardization process.