Zener Diode NXP BZV55-C6V8: Key Specifications and Application Circuits

The NXP BZV55-C6V8 is a popular Zener diode designed for voltage regulation and protection in a wide array of electronic circuits. As part of the small SOD-80 (MiniMELF) surface-mount package series, it offers a compact solution for stabilizing voltages in power supplies, reference circuits, and as protective clamps against overvoltage transients.

Key Specifications

The "C6V8" in its part number denotes its primary characteristic: a nominal Zener voltage of 6.8 V. This specific voltage is a common choice for protecting ICs and creating reference points, as many digital circuits operate at 5V logic levels, providing a comfortable safety margin.

Here are its critical specifications:

Zener Voltage (Vz): 6.8 V (measured at 5 mA)

Power Dissipation (Ptot): 500 mW maximum

Forward Voltage (VF): 1.2 V (at 200 mA)

Zener Impedance (ZZT): 10 Ω (at 5 mA)

Operating Temperature Range: -65 °C to +150 °C

Package: SOD-80 (MiniMELF)

The relatively low Zener impedance ensures a stable regulated voltage even with variations in current. The 500 mW power rating dictates the maximum current it can handle, calculated as Iz_max = P / Vz ≈ 73.5 mA. Proper series resistor selection is crucial to ensure the operating current stays within safe limits.

Application Circuits

The BZV55-C6V8 is versatile and can be implemented in several key circuits:

1. Basic Voltage Regulator

The most straightforward application is a simple shunt regulator. It is placed in parallel with the load it is protecting or powering. A series resistor (Rs) is connected to the input voltage (Vin). The value of Rs is chosen to limit the current such that the voltage across the Zener (and the load) remains at approximately 6.8V, even if Vin fluctuates or the load current changes.

2. Overvoltage Protection Clamp

Zener diodes are excellent for protecting sensitive integrated circuits (ICs) from voltage spikes on power lines. The BZV55-C6V8 is connected between the voltage rail (e.g., 5V) and ground, but in reverse bias. Under normal conditions, it draws negligible current. If a transient event causes the voltage to exceed 6.8 V, the Zener diode conducts, "clamping" the voltage to a safe level and shunting the excess current to ground, thereby protecting downstream components.

3. Voltage Reference

The stable breakdown voltage of the BZV55-C6V8 makes it suitable for creating a fixed reference point in circuits like analog-to-digital converters (ADCs), comparators, or voltage monitors. While dedicated reference ICs offer higher precision and stability, a Zener diode provides a cost-effective and simple solution for applications where extreme accuracy is not critical.

ICGOOODFIND: The NXP BZV55-C6V8 is a highly reliable and compact 6.8V Zener diode, ideal for voltage regulation, overvoltage protection, and creating stable reference points in modern electronic designs. Its SOD-80 package makes it perfect for space-constrained PCB layouts, offering robust performance for consumer and industrial applications.

Keywords: Zener Diode, Voltage Regulation, Overvoltage Protection, BZV55-C6V8, Voltage Reference