Aim of high power zener diode:
The aim of the design of this high power zener diode is a fast voltage regulator that can provide high currents. The circuit is based on a Type BUZ10 SIPMOS transistor, which has a high dissipation and can cope with high currents.
From an external power source, whose voltage must be about 2 V higher than the wanted stabilized potential, P1-C1-D1 derive a stable voltage in the range 0 – 6.8 V. This voltage switches ON T1, which in turn switches ON T2. If Uz drops slightly, the potential at the gate of T1 also drops, whereupon the T2 raises its on-resistance, so that the output voltage rises. The control speed is determined by R4.
High power zener diode circuit diagram:
The circuit, as drawn, delivers output voltages in the range 3.9 – 9.6 V at a supply voltage of 15 V. In the prototype an open-circuit voltage of 6 V was set (the current drawn by T2 was 490 mA), which dropped to 5.94 V when a load of 15 Ω (minimum value) was connected across T2 as shown in dashed lines.
The drain current was then 13 mA. The dynamic behavior is excellent: with a rectangular input signal at a frequency of 10 kHz, and a load of 15 Ω, the recovery time was smaller than 1 µs.