MA Series Axial Lead Varistors Datasheet by Littelfuse

Category: Electronics, Littelfuse Inc, Resistors

MA Series Axial Lead Varistors Overview

The MA Series are transient surge suppressors in the form of axial lead Metal Oxide Varistors (MOVs) designed for industrial and commercial electronic equipment. The series is engineered to shield components and signal/data lines from low-energy transients and is ideal for printed circuit board applications where a compact axial lead package is necessary.

Product Features and Options

These varistors come in a small 3mm diameter disc size for a snug fit and are available in a broad voltage operating range from 9V to 264V (MAC RMS) and 13V to 365V (MDC). Customers can select the series with standard (‘S’ suffix) or tightened (‘B’ suffix) clamping voltage. Varistors in the MA Series can be purchased in bulk or tape and reel packages. In terms of temperature resistance, the devices can operate without derating at up to 85°C ambient, and the new black epoxy coating offers enhanced high-temperature performance. They are also compatible with lead-free wave soldering processes.

Approvals and Specifications

Absence of Agency Approvals

It is worth noting that this series of varistors does not come with any stated agency approvals.

Absolute Maximum Ratings

The Absolute Maximum Ratings provide a reference for the limits within which the varistor should operate, to avoid permanent damage. They include continuous steady-state applied AC voltage ranging from 9 to 264V, and DC voltage from 13 to 365V. The transient peak pulse current reaches from 40 to 100A for an 8/20µs current wave, and the single-pulse energy range for a 2ms current square wave is between 0.06 to 1.7J. Furthermore, the MA Series can withstand various temperatures ranging from -55°C to +85°C for operating ambient, and -55°C to +125°C for storage. Additionally, the temperature coefficient of clamping voltage at specified test current is <0.01.

Electrical Characteristics and Ratings

The datasheet also details the Varistor Voltage at 1mA, Clamping Voltage at specific test currents, Peak Pulse Current, Energy, and DC Test Current for the device sizes at 25°C. Additional varistor parameters shown include the minimum and maximum voltage, clamping voltage, energy, current capacity, and typical capacitance values for the varistors across various product codes, helping users select the product best suited to their specific requirements.

Special Note

The provided average power dissipation for transient events should not exceed 200mW, which is an important consideration for the application of these varistors.

Information Validity and Availability

Lastly, the datasheet emphasizes that specifications are subject to change without prior notice. For the most current product information, users should visit the specified Littelfuse webpage.