我在一篇应用文档中看到这样一段话：
The LVPECL output stage requires a termination resistance of 50 Ω to the bias voltage of VCC – 2 V. This implies that the emitters of the pair of followers are around VCC – 1.3 V, because there is a 0.7-V drop across the base-emitter junction. The 0.7-V drop across the 50-Ω termination resistors results in a 14-mA flow through the PECL driver.
但怎么也看不出来和BE电压有什么关系。
但是从另一个角度分析，只考虑输出级的直流等效电路，当三极管基极接的电阻R=(1+β)*50时，可得出Vout=Vcc-1.35V，不知道对不对。
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