您好,
我目前需要使DP83867IR工作在1.8V的接口电压下,由于1.8V下LED灯很暗,我将电路根据datasheet 8.5.3节中的例子进行了连接。我想确认下,如果直接将LED口连接到三极管控制电路上(如图所示,其中LED0为DP83867IR的端口),strap是否工作在mode 1下?
谢谢!
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您好,
我目前需要使DP83867IR工作在1.8V的接口电压下,由于1.8V下LED灯很暗,我将电路根据datasheet 8.5.3节中的例子进行了连接。我想确认下,如果直接将LED口连接到三极管控制电路上(如图所示,其中LED0为DP83867IR的端口),strap是否工作在mode 1下?
谢谢!
您好,依据数据手册中Table4.4所述,当端口电压在0V时工作在strap mode1。在我附图的电路连接中,启动时LED_0正是0V,请问为什么在这种情况下不能工作在strap mode1?
谢谢!
您好,strap mode 的问题我已经确认,您的这个图确实可以工作在strap mode1 下,并且考虑到1.8V VDDIO LED 不亮,使用3.3V VDDIO这样做是符合Strap mode 1的, 请参考美国工程师的回复:user6461442 说:您好,依据数据手册中Table4.4所述,当端口电压在0V时工作在strap mode1。在我附图的电路连接中,启动时LED_0正是0V,请问为什么在这种情况下不能工作在strap mode1?
谢谢!
To clarify, DP8386IR/CR datasheet defines the strap modes as mode 1-4. The strap settings can be found in section 8.5 of the datasheet. The image you have shown above would be consistent with a mode 1 setting. Figure 27 shows a mode 2 setting. To convert Figure 27 to mode 3, the 10k resistor should be replaced by a 5.76k resistor.
Figure 26 in the datasheet, showing the direct pull-down to GND, is the mode 1 configuration used for a higher VDDIO level. As you mentioned the desired VDDIO level is 1.8V, the recommended mode 1 configuration would be as you have shown above, to ensure the LED will illuminate as expected.