SSTL_3, V, defined in EIA/JESD ; SSTL_2, V, defined in EIA/ JESDB used in DDR among other things. SSTL_18, V, defined in. STUB SERIES TERMINATED. LOGIC FOR VOLTS (SSTL_2). EIA/JESD SEPTEMBER ELECTRONIC INDUSTRIES ALLIANCE. JEDEC Solid State . SSTL (JESD, JESDB, JESD). • HSTL (JESD). LVTTL and LVCMOS were developed as a direct result of technology scaling. With each reduction in.
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Units V mV Notes 1 1 0. No claims to be in conformance with this standard may be made unless all requirements stated in the jezd8 are met. Viso Parameter Input clock signal offset voltage Viso variation Min. The test circuit is assumed to be similar to the circuit shown in figure 5. Units V V Notes 2. The output specifications are divided into two classes, Class I and Class II, which are distinguished by drive requirements and application. This is accomplished precisely because drivers and receivers are specified independently of each other.
The 9bb clause defines jese8 supply voltage requirements common to all compliant ICs. The system designer will be able to vary impedance levels, termination resistors and supply voltage and be able to calculate the effect on system voltage margins. In that case, the designer may decide to eliminate the series resistors entirely.
VTT is specified as being equal to 0. Class I or The tester may jese8 supply signals with a 1. The dc values are chosen such that the final logic state is unambiguously defined, that is once the receiver input has crossed this value, the receiver will change to and maintain the new logic state.
Stub Series Terminated Logic
Compliant devices must meet the VSwing ac specification under actual use conditions. However in order to provide a basis, the driver characteristics will be derived in terms of a typical 50?
All recipients of this errata are asked to replace page 7 with the corrected page included in this errata. The relationship of the different levels is shown in figure 1. The standard defines a reference voltage VREF which is used at the receivers as well as a voltage VTT to which termination resistors are connected. JEDEC standards and publications are adopted without regard to whether or not their adoption may involve patents or articles, materials, or processes.
Busses may be terminated by resistors to an external termination voltage. If the driver maintains a resistance lower than the Maximum On Resistance, more than the mV will be presented to the receiver.
The system designer can be sure that the device will switch state a certain amount of time after the input has crossed ac threshold and not switch back as long as the input stays beyond the dc threshold. The specifications are quite different from traditional 9n, where minimum values for VOH and iesd8 values for VOL are set that apply to the entire supply range. One advantage of this approach is that there is no need for a VTT power supply.
NOTE 4 AC test conditions may be measured under nominal voltage conditions as long as the supplier can demonstrate by analysis that the device will meet its timing specifications under all supported voltage conditions. This is illustrated in figure 2. By downloading this file the individual agrees not to charge for or resell the jesv8 material.
External resistors provide this isolation and also reduce the on-chip jese8 dissipation of the drivers. Figure 3 shows the typical dc environment that the output buffer is presented with. JEDEC is the leading developer of standards for the solid-state industry, they have published over documents to date. Clearly it is not the jrsd8 to show all possible variations in this standard.
AC 9n conditions may be measured under nominal voltage conditions as long as the supplier can demonstrate by analysis, that the device will meet its timing specifications under all supported voltage conditions. Under these conditions VOH is 1. See also figure 2. The standard is particularly intended to improve operation in situations where busses must be isolated from relatively large stubs. With a series resistor of 25?
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In some standards this ratio equals 0. NOTE 2 A 1. In this example a Class II type buffer might be preferred since it jesdd8 closer, in conjunction with the series resistor, jed8 match the characteristic impedance of the transmission line. The third clause specifies the minimum required output characteristics of, and ac test conditions for, compliant outputs targeted for various application environments.
Note however, that all timing specifications are still set relative to the differential ac input level. However, in the case of VIH Max. Note however, that all timing specifications are still set relative to the ac input level. This clause is added to set the conditions under which the driver ac specifications can be tested. The second clause defines the minimum dc and ac input parametric nesd8 and ac test conditions for inputs on compliant devices.