Article 3: TVS transient suppression diode selection tutorial (anti surge, anti-static, overvoltage protection)

TVS diodes are the core components of electronic product protection, mainly used for electrostatic protection, surge impact, and instantaneous overvoltage clamping. They are widely used in automotive, industrial control, communication, home appliances, and new energy equipment. Many devices have a high repair rate due to improper TVS selection and mismatched clamping voltage. diode

1、 Three core selection parameters for TVS

1. Working voltage Vrwm: must be greater than the normal working voltage of the circuit to avoid leakage and false clamping under normal conditions.

2. Breakdown voltage Vbr: determines the threshold for device startup protection, matched according to the upper limit of circuit withstand voltage.

3. Maximum pulse power Ppm: Based on the surge level of the equipment, higher power margin is required for on-board and industrial equipment.

2、 Selection taboos

Prohibit the use of low-voltage TVS for high-voltage circuits, as transient surges can directly cause breakdown; It is prohibited to use high-voltage TVS for low-voltage circuits, as it cannot provide protection.

3、 Typical application scenarios

Power port protection, signal interface anti-static, vehicle mounted equipment anti surge, charging pile auxiliary protection, industrial control equipment port lightning protection. diode

Common models: SMBJ, SMBJ6.5A, SMBJ12A, SMBJ24A and other universal TVS series, suitable for the vast majority of civil and industrial protection solutions.