Resistor values are typically 120 to 240 ohms for 3.3V operation and 82 to 120 ohms for 2.5V
operation.
Figure 7 - Pull Up Pull Down Termination
Resistor values are typically for 3.3V operation
For 2.5V operation, the resistor to ground is 62 ohms and the resistor to supply is 240 ohms
There are numerous application notes on terminating and interfacing PECL logic and the two most common methods are a single resistor to ground, Figure 6,
and a pull-up/pull-down scheme as shown in Figure 7. An AC coupling capacitor is optional, depending on the application and the input logic requirements of
the next stage.
One of the most important considerations is terminating the Output and Complementary Outputs equally. An unused output should not be left un-
terminated, and if one of the two outputs is left open it will result in excessive jitter on both. PC board layout must take this and 50 ohm impedance matching
into account. Load matching and power supply noise are the main contributors to jitter related problems.
LVDS Application Diagrams
+3.3V
OE or NC
10nF
1nF
1
6
Receiver
100
3
4
+3.3V
OE or NC
10nF
1nF
1
6
10nF
100
3
4
Receiver
OE or NC
2
5
OE or NC
2
5
10nF
Figure 8 - LVDS to LVDS, internal 100Ω
Some LVDS structures have an internal 100 ohm resistor on the
input and do not need additional components.
Figure 9 - LVDS to LVDS, External 100Ω and AC block ing caps
One of the most important considerations is terminating the Output and Complementary Outputs equally. An unused output should not be left un-
terminated, and if one of the two outputs is left open it will result in excessive jitter on both. PC board layout must take this and 50 ohm impedance matching
into account. Load matching and power supply noise are the main contributors to jitter related problems.
国际半导体设备材料产业协会（SEMI）昨（10）日公布半导体设备资本支出的年中预测报告（SEMI Capital Equipment Forecast），预估2012年全球半导体设备营收规模将达到423.8亿美元，2013年将成长至467.1亿美元。
受惠平板电脑、智慧型手机与行动装置等消费性电子商品亮丽表现，半导体设备的采购需求仍将持续。SEMI在报告中指出，2011年半...[详细]
stm32/stm8
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