Metal-Oxide Varistors (MOVs) Surface Mount Multilayer Varistors (MLVs) > MLA Automotive Series

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1 MLA Automotive Varistor Series RoHS Description The MLA Automotive Series of transient voltage surge suppression devices is based on the Littelfuse Multilayer fabrication technology. These components are designed to suppress a variety of transient events, including those specified in IEC or other standards used for Electromagnetic Compliance (EMC). The MLA Automotive Series is typically applied to protect integrated circuits and other components at the circuit board level. The wide operating voltage and energy range make the MLA Automotive Series suitable for numerous applications on power supply, control and signal lines. Size Table Metric EIA The MLA Automotive Series is manufactured from semiconducting ceramics, and is supplied in a leadless, surface mount package. The MLA Automtove Series is compatible with modern reflow and wave soldering procedures. It can operate over a wider temperature range than Zener diodes, and has a much smaller footprint than plastichoused components. Absolute Maximum Ratings For ratings of individual members of a series, see device ratings and specifications table. Continuous MLA Auto Series Units Steady State Applied Voltage: DC Voltage Range (V M(DC) ) 3.5 to 2 V AC Voltage Range (V M(AC)RMS ) 2.5 to 7 V Transient: Non-Repetitive Surge Current, 8/2µs up to Waveform, (I TM ) A Non-Repetitive Surge Energy, /µs Waveform, (W TM ) Operating Ambient Temperature Range (T A ). to 2.5 J -55 to +25 ºC Features AEC-Q qualified Halogen-Free and RoHS compliant Leadless 63, 85, 26 and 2 chip sizes Multilayer ceramic construction technology -55 C to +25 C operating temp. range Operating voltage range V M(DC) = 3.5V to 2V Rated for surge current (8 x 2µs) Rated for energy ( x µs) Inherent bi-directional clamping No plastic or epoxy packaging assures better than UL94V- flammability rating Standard low capacitance types available Load Dump energy rated per SAE Specification J3 Storage Temperature Range (T STG ) -55 to + ºC Applications Temperature Coefficient (αv) of Clamping Voltage (V C ) at Specified Test Current Additional Information Datasheet Resources <. %/º C Samples Suppression of inductive switching or other transient events such as EFT and surge voltage at the circuit board level ESD protection for IEC 6-4-2, MIL-STD- 883c method 35.7, and other industry specifications Provides on-board transient voltage protection for ICS and transistors Used to help achieve electromagnetic compliance of end products Replaces larger surface mount TVS Zeners in many applications

2 Device Ratings and Specifications Part Number Maximum Continuous Working Voltage Jump Start Voltage (5 min) Maximum Ratings (25º C) Load Dump Energy Maximum Non-repetitive Surge Current (8/2µs) Maximum Non-repetitive Surge Energy (/µs) Maximum Clamping Voltage at A (or as Noted) (8/2µs) Specifications (25ºC) Nominal Voltage at ma DC Test Current Typical Capacitance at f = MHz V M(DC) V M(AC) V JUMP W LD I TM W TM V C V N(DC) Min (V) (V) (V) (J) (A) (J) (V) (V) (V) (pf) V3.5MLA63NHAUTO V3.5MLA85NHAUTO V3.5MLA85LNHAUTO V3.5MLA26NHAUTO V5.5MLA63NHAUTO V5.5MLA85NHAUTO V5.5MLA85LNHAUTO V5.5MLA26NHAUTO V9MLA63NHAUTO V9MLA85LNHAUTO V2MLA85LNHAUTO V4MLA63NHAUTO V4MLA85NHAUTO V4MLA85LNHAUTO V4MLA26NHAUTO V8MLA63NHAUTO V8MLA85NHAUTO V8MLA85LNHAUTO V8MLA26NHAUTO V8MLA2NHAUTO at V26MLA63NHAUTO V26MLA85NHAUTO V26MLA85LNHAUTO V26MLA26NHAUTO V26MLA2NHAUTO at V3MLA63NHAUTO V3MLA85LNHAUTO V3MLA2NHAUTO at V3MLA2LNHAUTO at V33MLA26NHAUTO V42MLA26NHAUTO V48MLA2NHAUTO at V48MLA2LNHAUTO at V48MLA26NHAUTO V56MLA26NHAUTO V6MLA2NHAUTO at V68MLA26NHAUTO V85MLA2NHAUTO at V2MLA2NHAUTO at NOTES:. 'L' suffix is a low capacitance and energy version; Contact your Littelfuse sales representative for custom capacitance requirements 2. Typical leakage at 25ºC<25µA, maximum leakage µa at V M(DC) 3. Average power dissipation of transients for 63, 85, 26 and 2 sizes not to exceed.5w,.w,.w and.5w respectively 4. Load dump :min. time of energy input 4ms, interval 6sec(the load dump time constant Td differs from the time constant of energy input; load dump rating for ISO pulse 5a and ISO67-2 Table 5A. Please contact Littelfuse. V N(DC) Max C

3 Peak Current and Energy Derating Curve When transients occur in rapid succession, the average power dissipation is the energy (watt-seconds) per pulse times the number of pulses per second. The power so developed must be within the specifications shown on the Device Ratings and Specifications Table for the specific device. For applications exceeding 25 C ambient temperature, the peak surge current and energy ratings must be derated as shown below. PERCENT OF RATED VALUE Figure AMBIENT TEMPERATURE ( o C) FIGURE. PEAK CURRENT AND ENERGY DERATING CURVE Peak Pulse Current Test Waveform for Clamping Voltage PERCENT OF PEAK VALUE O Figure 2 T T EXAMPLE: FOR AN 8/2 s CURRENT WAVEFORM 8 s = t = VIRTUAL FRONT TIME 2 s = t 2 = VIRTUAL TIME TO HALF VALUE T 2 = Virtual Origin of Wave T = Time from % to 9% of Peak FIGURE T 2. PEAK PULSE CURRENT TEST WAVEFORM = Rise Time =.25 x T FOR CLAMPING VOLTAGE T 2 = Decay Time Example - For an 8/2 µs Current Waveform: O = VIRTUAL ORIGIN OF WAVE t = TIME 8µs FROM = T % = Rise TO 9% Time OF PEAK t = VIRTUAL 2µs = FRONT T TIME =.25 x t 2 = Decay Time t 2 = VIRTUAL TIME TO HALF VALUE (IMPULSE DURATION) TIME

4 Limit V-I Characteristic for V3.5MLA63NHAUTO to V3MLA63NHAUTO Limit V-I Characteristic for V3.5MLA85LNHAUTO to V3MLA85LNHAUTO V3MLA85LNHAUTO V3MLA63NHAUTO V26MLA85LNHAUTO V26MLA63NHAUTO V8MLA63NHAUTO V4MLA63NHAUTO V8MLA85LNHAUTO V4MLA85LNHAUTO V9MLA63NHAUTO, V9MLA63LNHAUTO V5.5MLA63NHAUTO, V5.5MLA63LNHAUTO V3.5MLA63NHAUTO µa µa ma ma ma A A A Current (A) Figure 3 Figure 4 V2MLA85LNHAUTO V9MLA85LNHAUTO V5.5MLA85LNHAUTO V3.5MLA85LNHAUTO µa µa ma ma ma A A A Current (A) Limit V-I Characteristic for V3.5MLA85NHAUTO to V26MLA85NHAUTO FIGURE X. LIMIT V-I CHARACTERISTIC FOR V3.5MLA63NHAUTO TO V3MLA63NHAUTO Limit V-I Characteristic for V3.5MLA26NHAUTO to V42MLA26NHAUTO FIGURE X. LIMIT V-I CHARACTERISTIC FOR V3.5MLA85LNHAUTO TO V3MLA85LNHAUTO V3MLA85LNHAUTO V26MLA85LNHAUTO V8MLA85LNHAUTO V4MLA85LNHAUTO V3.5MLA85LNHAUTO µa µa ma ma ma A A A Current (A) V2MLA85LNHAUTO V9MLA85LNHAUTO V5.5MLA85LNHAUTO Figure 5 FIGURE X. LIMIT V-I CHARACTERISTIC FOR V3.5MLA85LNHAUTO TO V3MLA85LNHAUTO Limit V-I Characteristic for V8MLA2NHAUTO to V48MLA2NHAUTO V42MLA26NHAUTO V33MLA26NHAUTO V26MLA26NHAUTO V8MLA26NHAUTO V8MLA26 V4MLA26 V4MLA26NHAUTO V5.5MLA26 V5.5MLA26NHAUTO V3.5MLA26 V3.5MLA26NHAUTO µa µa ma ma ma A A A A Current (A) Figure 7 FIGURE 6. LIMIT V- CHARACTERISTIC FOR V3.5MLA26 TO V68MLA26 V48MLA26NHAUTO V68MLA26NHAUTO V56MLA26NHAUTO V2MLA2NHAUTO V85MLA2NHAUTO V6MLA2NHAUTO V48MLA2NHAUTO, V48MLA2LNHAUTO V3MLA2NHAUTO, V3MLA2LNHAUTO V26MLA2NHAUTO V8MLA2NHAUTO Figure 6 µa µa ma ma ma A A A A CURRENT (A) FIGURE X. LIMIT V-I CHARACTERISTIC FOR V8MLA2NHAUTO TO V2MLA2NHAUTO

5 Device Characteristics Clamping Voltage Over Temperature (V C at A) 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 modex (approaching 6 Ω at its maximum rated working voltage). Leakage currents at maximum rated voltage are below µa, typically 25µA. Typical Temperature Dependance of the Haracteristic Curve in the Leakage Region % CLAMPING VOLTAGE (V) V26MLA26 V5.5MLA26 SUPPRESSOR VOLTAGE IN PERCENT OF V NOM VALUE AT 25 o C (%) o o o o 25 o C % E -9 E -8 E -7 E -6 E -5 E -4 E -3 E -2 SUPPRESSOR CURRENT (ADC ) FIGURE. TYPICAL TEMPERATURE DEPENDANCE OF THE CHARACTERISTIC CURVE IN THE LEAKAGE REGION Figure 8 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 ns and the MLA Automotive Series 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. Multilayer Internal Construction FIRED CERAMIC DIELECTRIC -6 Figure TEMPERATURE ( o C) FIGURE 2. CLAMPING VOLTAGE OVER TEMPERATURE (V C AT A) Energy Absorption/Peak Current Capability Energy dissipated within the MLA Automotive Series is calculated by multiplying the clamping voltage, transient current and transient duration. An important advantage of the multilayer is its interdigitated electrode construction within the mass of dielectric material. This results in excellent current distribution and the peak temperature per energy absorbed is very low. The matrix of semiconducting grains combine to absorb and distribute transient energy (heat) (see Speed of Response). This dramatically reduces peak temperature; thermal stresses and enhances device reliability. As a measure of the device capability in energy and peak current handling, the V26MLA26 part was tested with multiple pulses at its peak current rating (A, 8/2µs). At the end of the test,, pulses later, the device voltage characteristics are still well within specification. Repetitive Pulse Capability PEAK CURRENT = 3A 8/2 s DURATION, 3s BETWEEN PULSES METAL ELECTRODES VOLTAGE V26MLA26 METAL END TERMINATION Figure DEPLETION REGION DEPLETION REGION GRAINS Figure NUMBER OF PULSES FIGURE 3. REPETITIVE PULSE CAPABILITY FIGURE. MULTILAYER INTERNAL CONSTRUCTION

6 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 MLA Automotive Series suppressor is a 62/36/2 (Sn/Pb/Ag), 6/4 (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. When using a reflow process, care should be taken to ensure that the MLA Automotive Series chip is not subjected to a thermal gradient steeper than 4 degrees per second; the ideal gradient being 2 degrees per second. During the soldering process, preheating to within degrees of the solder's peak temperature is essential to minimize thermal shock. Once the soldering process has been completed, it is still necessary to ensure that any further thermal shocks are avoided. One possible cause of thermal shock is hot printed circuit boards being removed from the solder process and subjected to cleaning solvents at room temperature. The boards must be allowed to cool gradually to less than º C before cleaning. Lead free (Pb-free) Soldering Recommendations Littelfuse offers the Nickel Barrier Termination option (see "N" suffix in Part Numbering System for ordering) for the optimum Lead free solder performance, consisting of a Matte Tin outer surface plated on Nickel underlayer, plated on Silver base metal. The preferred solder is 96.5/3./.5 (SnAgCu) with an RMA flux, but there is a wide selection of pastes and fluxes available with which the Nickel Barrier parts should be compatible. The reflow profile must be constrained by the maximums in the Lead free Reflow Profile. For Lead free wave soldering, the Wave Solder Profile still applies. Note: the Lead free paste, flux and profile were used for evaluation purposes by Littelfuse, based upon industry standards and practices. There are multiple choices of all three available, it is advised that the customer explores the optimum combination for their process as processes vary considerably from site to site. Reflow Solder Profile TEMPERATURE TEMPERATURE C C C PREHEAT ZONE TIME (MINUTES) Figure 2 TIME (MINUTES) FIGURE REFLOW.5 SOLDER PROFILE FIGURE 4. REFLOW TIME (MINUTES) SOLDER PROFILE Wave Solder Profile TEMPERATURE TEMPERATURE C C C MAXIMUM TEMPERATURE MAXIMUM 23 C TEMPERATURE 23 C 4-8 MAXIMUM TEMPERATURE SECONDS 23 C 4-8 ABOVE SECONDS 83 C ABOVE 83 C RAMP RATE 4-8 SECONDS RAMP <2 C/sRATE ABOVE 83 C <2 C/s PREHEAT DWELL RAMP RATE PREHEAT DWELL <2 C/s PREHEAT PREHEAT PREHEAT ZONEDWELL MAXIMUM WAVE 26 C MAXIMUM WAVE 26 C SECOND PREHEAT SECOND PREHEAT FIRST PREHEAT SECOND PREHEAT FIRST PREHEAT FIRST PREHEAT Figure TIME 2.(MINUTES) TIME (MINUTES)..5 FIGURE WAVE 2. SOLDER 2.5 PROFILE FIGURE 5. WAVE TIME SOLDER (MINUTES) PROFILE 3 3 MAXIMUM TEMPERATURE 26 C, MAXIMUM TIME WITHIN TEMPERATURE 5 C OF PEAK26 C, 2 TIME 2 SECONDS WITHIN 5 C MAXIMUM OF PEAK MAXIMUM SECONDS TEMPERATURE MAXIMUM RAMP RATE 26 C, TIME WITHIN 5 C OF RAMP <3 C/s PEAK RATE 6 - SEC 2 2 SECONDS MAXIMUM <3 C/s 6 > - 27 C SEC RAMP RATE > 27 C <3 C/s 6 - SEC > 27 C PREHEAT ZONE PREHEAT ZONE PREHEAT ZONE TIME 3. (MINUTES) TIME (MINUTES) FIGURE. 6. LEAD-FREE RE-FLOW 4. SOLDER 5. PROFILE Figure 4 FIGURE 6. LEAD-FREE TIME (MINUTES) RE-FLOW SOLDER PROFILE TEMPERATURE TEMPERATURE C C C FIGURE 4. REFLOW SOLDER PROFILE MAXIMUM WAVE 26 C FIGURE 5. WAVE SOLDER PROFILE Lead free Re-flow Solder Profile FIGURE 6. LEAD-FREE RE-FLOW SOLDER PROFILE

7 Product Dimensions (mm) PAD LAYOUT DIMENSIONS C CHIP LAYOUT DIMENSIONS E B NOTE D L W A NOTE : Avoid metal runs in this area, parts not recommended for use in applications using Silver (Ag) epoxy NOTE: paste. Avoid metal runs in this area. Parts not recommended for use in Dimension 2 applications Size using silver epoxy 26 paste. Size 85 Size 63 Size IN MM IN MM IN MM IN MM A B C D (max.) E L W.2 -/ /+.2. -/+.2. -/ / / / / /+.. -/ / / / / /+.8. -/ / / / / / / / /+.5 Part Numbering System V 8 MLA26 X X DEVICE FAMILY Littelfuse TVSS Device MAXIMUM DC WORKING VOLTAGE MULTILAYER SERIES DESIGNATOR DEVICE SIZE: 63 =.63 inch x.3 inch (.6 mm x.8 mm) 85 =.8 inch x.8 inch (2. mm x.25 mm) 26 =.26 inch x.63 inch (3.2 mm x.6 mm) 2 =.26 inch x. inch (3.2 mm x 2.5 mm) X AUTO AUTOMOTIVE SERIES PACKING OPTIONS (see Packaging table for quantities) H: 7in (78mm) Diameter Reel, Plastic Carrier Tape END TERMINATION INDICATOR N: Nickel Barrier (Matte Tin outer surface, plated on Nickel underlayer plated on silver base metal) CAPACITANCE OPTION No Letter: Standard L: Low Capacitance Version Packaging* Quantity Device Size 7 Inch Reel ("H" Option) 2 2, 26 2, 85 2, 63 2, *(Packaging) It is recommended that parts be kept in the sealed bag provided and that parts be used as soon as possible when removed from bags.

8 Tape and Reel Specifications D P P 2 E For T and H Pack Options: PLASTIC CARRIER TAPE For R Pack Options: EMBOSSED PAPER CARRIER TAPE PRODUCT IDENTIFYING LABEL F W K B t D P A EMBOSSMENT TOP TAPE 8mm NOMINAL 78mm OR 33mm DIA. REEL Symbol Description Dimensions in Millimeters 63, 85, 26 & 2 Sizes A Width of Cavity Dependent on Chip Size to Minimize Rotation. B Length of Cavity Dependent on Chip Size to Minimize Rotation. K Depth of Cavity Dependent on Chip Size to Minimize Rotation. W Width of Tape 8 -/+.3 F Distance Between Drive Hole Centers and Cavity Centers 3.5 -/+.5 E Distance Between Drive Hole Centers and Tape Edge.75 -/+. P Distance Between Cavity Centers 4 -/+. P 2 Axial Drive Distance Between Drive Hole Centers & Cavity Centers 2 -/+. P Axial Drive Distance Between Drive Hole Centers 4 -/+. D Drive Hole Diameter.55 -/+.5 D Diameter of Cavity Piercing.5 -/+.5 T Top Tape Thickness. Max NOTES: Conforms to EIA-48-, Revision A Can be supplied to IEC publication Disclaimer Notice - Information furnished is believed to be accurate and reliable. However, users should independently evaluate the suitability of and test each product selected for their own applications. Littelfuse products are not designed for, and may not be used in, all applications. Read complete Disclaimer Notice at