2015年8月26日 · Figure 5: Buffered Zener regulator circuits. This regulator has low output impedance, meaning that the voltage will not droop much with load. This circuit can be built with a MOSFET or a BJT. The output voltage is Vz-Vt for a Zener regulator with a MOSFET buffer, or Vz-Vbe for a Zener regulator with a BJT current buffer.

2024年1月2日 · Probably the simplest type of voltage regulator is the zener shunt stabilizer, which works by using a basic zener diode for the regulation, as demonstrated in Figure below. The zener diodes have a voltage rating equivalent to the intended output voltage, that may be closely match the desired output value.

An NPN BJT wired as an Emitter follower, which has a fixed voltage at the Base thanks to a zener diode, acts as a voltage regulator. The Emitter voltage will be 0.6V less than the voltage at the Base. Using a 5.6V zener diode, you can hold approx. 5V across a …

2022年6月27日 · If you are willing to assume that the series current through \$R\$ and the zener diode is very large with respect to the base current required by \$Q_1\$, then it follows that the voltage at the base of \$Q_1\$ is fixed and determined by the zener diode.

2017年11月20日 · Finally, you can see that the node at the BJT emitter receives the collector current and the base current as incoming currents and that the load current equals the sum of those. It all works out just fine.

A voltage regulator with a transistor usually consists of a bipolar junction transistor (bjt) with high current handling capability in an emitter follower configuration, driven by zener diode and resistor potential divider (PD) network. We first use a Zener diode and resistor across the input rail to make a PD that provides a regulated output.

A zener diode can be used to set the Base voltage of Bipolar Junction Transistor (BJT) Current Source. That voltage, offset by approx. 0.6V, will be across the Emitter’s current setting resistor regardless the supply voltage.

2013年8月17日 · If the schematic has a zener, I'd use a zener - I wouldn't trust a bjt breakdown voltage to be reliable (voltage level wise) or low noise. Many zeners are designed specifically to be low-noise - get one of those.

Transistor-Zener Diode Regulator Circuits. by Lewis Loflin. Updated, revised October 2016. This will explore the basic operation of Zener diodes and their use as voltage regulators. They will be used in conjunction with common bi-polar transistors to boost the output current and can used for real-world voltage regulators by students and hobbyists.

The zener diode provides the voltage reference, and the base to emitter voltage of the transistor is the control voltage. The value of RS must be sufficiently small, to keep the zener in its reverse breakdown region.