vo输出电压增大→tl431参考极电压增大→tl431阴极与阳极压降降低、电流增大→光耦初级电流增大→光耦次级电流增大→fb脚电压升高→电源管理芯片降低mos管的占空比→vo输出电压减小。反之亦然，如此保障输出电压平稳。 参数选择： ...

一、前言 参考电压源tl431被广泛使用在信号采集电路中。在它的数据手册中，给出了在稳压输出端负载电容对输出稳定性的影响。可以看到，在不同的稳压输出以及工作电流下，输出负载中的电容会使得参考电压输出 ...

由于Ib和TL431反馈脚的电流很小很小，可以忽略不计，所以这个恒流源可以由下式计算： Io = 2.495V / Rref 以上恒流源电路在合理范围改变Rload的大小 ...

LTwiki, The TL431 spice model; Texas Instruments, Spice model of the TL431; Video of the VCO in action; Download the LTSpice files (“save as”, then, remove the .txt extension). Also see: TL431 Model; ...

In designs that omit a voltage amplifier, a shunt regulator can serve as an inexpensive op amp. Resistors R I and R set the power supply’s dc output voltage, and optocoupler IC 2 provides galvanic ...

Since the TL431 imposes 2.5 V across R low, then with a 1 mA current imposed by R upp, R low becomes 2.5 V/1 mA = 2.5 kΩ. Then, R upp simply equals 12 V- 2.5 V/1 mA = 9.5 kΩ.

And for a truly esoteric use of the TL431, here’s a crystal radio design that abuses the TL431 as an audio amplifier. What do you think of Ralph’s charger design?

Inside the TL431, [Ken] discovers that transistors aren’t made up of the three layer NPN or PNP sandwich we’ve come to know and love. In fact, the base isn’t even in the middle.