The difference between BNC connectors and SMA connectors

RF connectors, also known as RF connectors, are usually considered as components installed on cables or instruments. They serve as electrical connections or separation components for transmission lines, mainly serving as bridges. There are many types of RF connectors. Today, let's take a look at the differences between BNC connectors and SMA connectors.

 Definition
1) BNC connector
BNC connector is also one of the commonly seen RF connectors, which is a small plug-in connector that can achieve quick connection. The full name of BNC is Bayonet Nut Connector (buckle fit connector, which vividly describes the appearance of this connector). The original meaning of BNC (Bayonet Neill – Concelman) actually came from the first letters of the surnames of Paul Neill and Carl Concelman, who were also inventors of the N-type connector. BNC connectors are widely used in wireless communication systems, televisions, testing equipment, and other RF electronic devices. Early computer networks also used BNC connectors. The BNC connector supports a signal frequency range of 0 to 4GHz. There are two types of characteristic impedances: 50 ohms and 75 ohms.

2) SMA connector
SMA connector is a widely used coaxial connector with small threaded connections, which has the characteristics of wide frequency band, excellent performance, high reliability, and long service life. SMA connectors are suitable for connecting RF cables or microstrip lines in the RF circuits of microwave devices and digital communication systems. They are commonly used on wireless devices for GPS clock interfaces on single boards and testing ports for base station RF modules. The SMA connector was invented in the 1960s. The signal frequency range supported by SMA connectors ranges from DC to 18GHz, and some types can support up to 26.5GHz. The characteristic impedance is 50 ohms.

 Difference

1) Different frequency ranges: BNC connectors are suitable for frequencies ranging from 0 to 4GHz, while SMA connectors are suitable for frequencies ranging from 0 to 18GHz.

2) Different uses: BNC is a low-power coaxial cable connector with a bayonet connection mechanism. SMA is suitable for microwave applications that require high performance, such as internal connections of microwave equipment.

3) Advantages differ: BNC can quickly connect and separate, with characteristics such as reliable connection, good vibration resistance, and convenient connection and separation, making it suitable for frequent connection and separation situations. SMA has the characteristics of small size, superior performance, high reliability, and long service life.