This article presents practical techniques for incorporating `correctness by design` in DDR2 interfaces, from a Signal Integrity (SI) perspective, using the current generation of available design tools. Some common DDR2 design errors are analyzed, as well as the tradeoffs between some popular design alternatives. Several possible address/control t
Click here to download the full size of the above Circuit.
opologies for DDR2 shown in Fig 1, while several possible data topologies are illustrated in Fig 2. In order to make use of the FPGA`s on-die digitally controlled impedance (DCI), the memory chip was made the driver and the 65nm FPGA device the receiver on the bi-directional data lines. The top schematic diagram in Fig 1 shows the preferred and recommended use model, while the other figures illustrate variations often attempted in regular design practice. The input switching thresholds of the receiver are shown as horizontal dashed blue lines for reference. The color of the "probe" arrows in Fig 1 and Fig 2 correspond to the colors of the associated traces in Fig 3 and Fig 4, respectively. Mentor Graphics` HyperLynx software was used to generate eye diagrams with the following parameter settings:
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This....
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,....
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
characters left: