JEDEC JESD8‐25

Abstract

This document defines the 1.0 V Pseudo Open Drain Interface family of interface standards, POD10, which are generally expected to be implemented with differential amp-based input buffers that, when in singleended mode, employ an externally supplied (or internal supplied) reference voltage controlled trip-point. <br>Although this specification is named for the nominal value of VDDQ to be used, it is the input trip-point value that provides for inter operability of POD10 compliant devices. Physics dictates variations in output driver characteristics and termination values in different interconnect network topologies. Drivers and terminators appropriate in a point-to-point interconnect scheme are not necessarily suitable in a multi-drop bus application. Multiple Classes of POD10 are expected to reside within the family of POD10 interfaces in order to accommodate various device and market applications. The various classes standardized within the context of POD10 are documented in the appendices of this document (e.g. POD10/Class A, POD10/Class B, POD10/Class C, etc.) <br>In all cases, drivers and terminators are expected to produce a roughly symmetric swing about the input trippoint of POD10 receivers. Unlike the signals on other interfaces, such as HSTL, that are designed to produce signals that swing symmetrically about VDDQ/2, the signals on a POD10 interconnect line are not generally expected to pull to VSS. POD10 input buffers are generally expected to be supported by pull-uponly parallel input termination. POD10 output drivers are therefore expected to demonstrate an asymmetric output drive impedance. In point-to-point applications, for example, if the output drivers were expected to demonstrate a nominal 60 ohm pull-up drive impedance then the pull-down drivers would be expected to produce a 40 ohm pull-down drive impedance. <br>The core of this standard defines the dc and ac single-ended and differential operating conditions for POD10 input buffers as well as the terms and definitions necessary to describe the characteristics and behavior of output drivers. Section 2 in this document documents the subset of values common to all Classes of POD10 and documents specification items left to definition within a specific Class. The values specific to each particular class of POD10 are found in the appendices. (Note it does not follow that all specification values defined in a given Class are necessarily different from the matching parameter in other Class within POD10. Multiple Classes may reuse a given specification value if appropriate to the Class requirements.) <br>Inasmuch as additional classes may be added to this specification at the will of the authorizing committee and the JEDEC Board of Directors, the reader is advised to check the JEDEC website (http://www.jedec.org) for the latest release of the specification.