Documentation for Product Control is concerned with all aspects of the product. Any aspect from the business area that may require a phone system, better web presence, inter-departmental collaboration tools, etc., deal directly with specifying a product or technology that may not exist yet or is currently used, and the recommendation and technology life cycle that follows.
For example, if a business is growing and needs to expand it's phone system in a number of new locations, the overall strategy may be to build a Business Plan to move to a converged voice & data platform. A cost/benefit analysis would be conducted that would look at current and proposed Technical Architectures affecting voice and data networks as well as some hardware (client and server) and software (custom or COTS) such as the use of softphone technology.
A good method of determing a cost/benefit analysis is to provide a Request For Proposal (RFP) to a list of vendors. The vendors will respond with a proposal that will define their solution as well as cost benefit analysis and architecture benefit analysis. The response will generally be the basis of, or actual, Statement Of Work (SOW) that is used for the basis of the contract. It will also define what work will be done and what documentation will be delivered along with the work.
The picture below identifies typical product documentation throughout the lifecycle of a project that one would expect to be delivered as part of a project.