 
 <prompt> Wetin some diodes dey made from? Given di previous question, write one context wey contain di answer. E fit be 1 - 20 sentences. Context: <response>: LEDs don also dey use as medium-quality voltage reference for electronic circuits. The forward voltage drop (e.g. about 1.7 V for a normal red LED) fit dey use instead of Zener diode for low-voltage regulators. Red LEDs get flat I/V curve above the knee. Nitride-based LEDs get steep I/V curve and no fit use for this purpose. Even though LED forward voltage dey depend well on current pass Zener diode, Zener diodes wey get breakdown voltages below 3 V no dey plenty for market. 