Varistor Metal Oxide Varistor Products Page 25 Varistor Metal-Oxide Varistor Products

2017 Littelfuse, Inc. Specifications are subject to change without notice. Revised: 09/14/17 Metal-Oxide Varistors (MOVs) Surface Mount Multilayer Varistors (MLVs) > MHS Series 60 10 1 Number of Pulses NOMINAL VOLTAGE AT 1mADC 10 100 1000 10000 20 30 40 50 V0402MHS03 V0402MHS12 V0603MHS03 V0603MHS12 0 V0402MHS22 V0603MHS22 Nominal Voltage Stability to Multiple ESD Impulses (8kV Contact Discharges per IEC 61000-4-2) Insertion Loss (S21) Characteristics -30 FREQUENCY (MHz) INSERTION LOSS (dB) 10 100 1000 10000 -20 -10 0 V0402MHS22 V0603MHS22 V0402MHS12 V0402MHS03 V0603MHS12 V0603MHS03 Figure 3 Figure 4 Lead (Pb) Soldering Recommendations The principal techniques used for the soldering of components in surface mount technology are IR Re-flow and Wave soldering. Typical profiles are shown on the right. The recommended solder for the MHS suppressor is a 62/36/2 (Sn/Pb/Ag), 60/40 (Sn/Pb) or 63/37 (Sn/Pb). Littelfuse also recommends an RMA solder flux. Wave soldering is the most strenuous of the processes. To avoid the possibility of generating stresses due to thermal shock, a preheat stage in the soldering process is recommended, and the peak temperature of the solder process should be rigidly controlled. 230 Reflow Solder Profile Device Characteristics At low current levels, the V-I curve of the multilayer transient voltage suppressor approaches a linear (ohmic) relationship and shows a temperature dependent effect. At or below the maximum working voltage, the suppressor is in a high resistance model (approaching 10 6 at its maximum rated working voltage). Leakage currents at maximum rated voltage are below 100 A, typically 25 A; for 0402 size below 20 A, typically 5 A. 100% 1E -9 1E -8 SUPPRESSOR CURRENT (A DC ) 10% 1E -7 1E -6 1E -5 1E -4 1E -3 1E -2 25 50 75 100 125 o C SUPPRESSOR VOLTAGE IN PERCENT OF V NOM VALUE AT 25 o C (%) o Typical Temperature Dependance of the Characteristic Curve in the Leakage Region Speed of Response The Multilayer Suppressor is a leadless device. Its response time is not limited by the parasitic lead inductances found in other surface mount packages. The response time of the Z N O dielectric material is less than 1ns and the MLE can clamp very fast dV/dT events such as ESD. Additionally, in "real world" applications, the associated circuit wiring is often the greatest factor effecting speed of response. Therefore, transient suppressor placement within a circuit can be considered important in certain instances. GRAINS DEPLETION FIRED CERAMIC DIELECTRIC REGION METAL ELECTRODES DEPLETION REGION METAL END TERMINATION Multilayer Internal Construction Figure 5 Figure 6 Figure 7

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