MMBZ5257B-7-F
Compact 33V Zener diodes in SOT-23 package for voltage regulation
Manufacturer： ['diodes', 'diodes-zetex', 'diodeszetex']
series introduction
# Introduction to the MMBZ5257B - 7 - F Product Series
## 1. Overview
The MMBZ5257B - 7 - F product series belongs to the realm of semiconductor components, specifically Zener diodes. These diodes play a crucial role in electronic circuits, providing a stable reference voltage and protecting sensitive components from over - voltage conditions. The series is designed to meet the requirements of various applications, offering reliable performance and high - quality characteristics.
## 2. Key Specifications
### Electrical Characteristics
- **Zener Voltage (Vz)**: The MMBZ5257B - 7 - F has a well - defined Zener voltage. For this particular series, the Zener voltage is typically around 18V. This voltage remains relatively constant over a wide range of currents, making it suitable for applications where a stable voltage reference is needed.
- **Tolerance**: It offers a tight tolerance on the Zener voltage. Usually, the tolerance is within a few percent (e.g., ± 5%), ensuring that the actual Zener voltage in a circuit is close to the specified value. This precision is essential for accurate voltage regulation in sensitive electronic systems.
- **Power Dissipation (Pd)**: The series is designed to handle a certain amount of power. The power dissipation rating of the MMBZ5257B - 7 - F is typically in the range of several hundred milliwatts (e.g., 500mW). This allows it to operate in circuits where it may need to dissipate energy when regulating the voltage.
- **Dynamic Resistance (Zz)**: The dynamic resistance of the Zener diode is an important parameter. It represents the change in voltage with respect to the change in current. A low dynamic resistance (e.g., a few ohms) indicates that the Zener voltage remains stable even when the current through the diode changes, providing better voltage regulation.
### Physical Characteristics
- **Package Type**: The MMBZ5257B - 7 - F comes in a small - sized surface - mount package. This package is designed for easy integration onto printed circuit boards (PCBs). The compact size makes it suitable for applications where space is limited, such as in mobile devices, portable electronics, and miniaturized circuit designs.
- **Lead - Free and RoHS - Compliant**: In line with modern environmental standards, the product series is lead - free and compliant with the Restriction of Hazardous Substances (RoHS) directive. This ensures that the diodes are environmentally friendly and can be used in products that need to meet strict environmental regulations.
## 3. Working Principle
A Zener diode like the MMBZ5257B - 7 - F operates based on the Zener effect. When the reverse - bias voltage across the diode reaches the Zener voltage, the diode starts to conduct current in the reverse direction. Unlike a normal diode, which would break down catastrophically under reverse - bias conditions, a Zener diode maintains a relatively constant voltage across its terminals as the current through it increases. This property allows it to be used as a voltage regulator.
In a circuit, when the input voltage exceeds the Zener voltage, the Zener diode conducts and shunts the excess current, keeping the output voltage at the Zener voltage level. This protects other components in the circuit from being exposed to over - voltage conditions.
## 4. Applications
### Voltage Regulation
- **Power Supplies**: In both linear and switching power supplies, the MMBZ5257B - 7 - F can be used to provide a stable reference voltage. It helps in maintaining a constant output voltage, even when the input voltage or load current varies. For example, in a battery - powered device, it can ensure that the voltage
Images for reference
SOT23
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