onsemi 1N5925BRLG Zener Diode: Key Specifications and Application Circuit Design

The 1N5925BRLG from onsemi is a popular 12V Zener diode belonging to the 1.5W series, widely recognized for its robust voltage regulation and protection capabilities in various electronic circuits. This component is engineered to provide a stable reference voltage or to clamp voltage spikes, making it indispensable in power supplies, voltage regulators, and protection circuits.

Key Specifications

The 1N5925BRLG is characterized by its Zener voltage (Vz) of 12V with a tolerance of ±5%. It boasts a maximum power dissipation of 1.5W at a test temperature of 25°C, ensuring reliable performance under substantial load conditions. The device operates effectively over a wide temperature range from -65°C to +200°C, making it suitable for harsh environments. Its forward voltage is typically 1.2V, and it can handle a maximum reverse leakage current of 5μA at the working voltage. Housed in a DO-41 package, it is designed for through-hole mounting, facilitating easy integration into various circuit boards.

Application Circuit Design

A common application of the 1N5925BRLG is in voltage regulation circuits. For instance, in a simple shunt regulator, the Zener diode is placed in parallel with the load. To design such a circuit, the series resistor (Rs) must be calculated to limit the current through the Zener, ensuring it operates within its specified power rating. The formula Rs = (Vin - Vz) / Iz is used, where Vin is the input voltage, Vz is the Zener voltage (12V), and Iz is the Zener current, which must be between the minimum knee current (IZK) and the maximum current (IZM) derived from the power rating (IZM = Pmax / Vz ≈ 125mA for 1.5W).

Another critical application is in over-voltage protection circuits. Here, the Zener diode is connected across the input of a sensitive component. When the input voltage exceeds 12V, the diode conducts, shunting the excess current to ground and protecting the downstream circuitry. This is particularly useful in safeguarding microcontrollers or ICs from voltage transients.

ICGOODFIND Summary

The onsemi 1N5925BRLG is a highly reliable 12V, 1.5W Zener diode ideal for voltage regulation and protection tasks. Its key strengths include a precise voltage reference, high power handling, and a robust operating temperature range, making it a versatile choice for diverse electronic designs.

Keywords:

Zener Diode, Voltage Regulation, Over-Voltage Protection, Power Dissipation, Circuit Design