SMS Volt TVS Array For ESD and Latch-Up Protection. PROTECTION PRODUCTS Description. Features. Mechanical Characteristics.

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1 Description The SMS series of TS arrays are designed to protect sensitive electronics from damage or latch-up due to ESD, lightning, and other voltage-induced transient events. Each device will protect up to four lines operating at 3.3 volts. The SMS3.3 is a solid-state device designed specifically for transient suppression. It is constructed using Semtech s proprietary EPD process technology. The EPD process provides low standoff voltages with significant reductions in leakage currents and capacitance over traditional pn junction processes. They offer desirable characteristics for board level protection including fast response time, low clamping voltage and no device degradation. The SMS3.3 may be used to meet the immunity requirements of IEC 6-4-2, level 4 (±15k air, ±8k contact discharge). The low cost SOT23-6L package makes them ideal for use in portable electronics such as cell phones, PDs, and notebook computers. SMS olt TS rray For ESD and Latch-Up Protection Features Transient protection for data lines to IEC (ESD) ±15k (air), ±8k (contact) IEC (EFT) 4 (5/5ns) IEC (Lightning) (8/2µs) Protects four I/O lines Working voltage: 3.3 Low leakage current (<1µ) Low clamping voltage Solid-state EPD TS technology Mechanical Characteristics EIJ SOT23-6L package Molding compound flammability rating: UL 94- Marking : Marking Code Packaging : Tape and Reel per EI 481 Lead Finish: Matte tin RoHS/WEEE Compliant pplications Cell phone Handsets and ccessories Microprocessor Based Equipment Personal Digital ssistants (PDs) and Pagers Industrial Equipment Notebook Computers Portable Instrumentation Peripherals Equivalent Circuit Diagram Schematic & PIN Configuration SOT23-6L (Top iew) Revision 1/4/7 1 United States Patent No.

2 bsolute Maximum Rating Rating Symbol alue Units Peak Peak Pulse Power (tp = 8/2µs) Pulse Current (tp = 8/2µs) ESD oltage (HBM Waveform per IEC 6-4-2) P pk 1 Watts PP 3 k Operating Temperature T J -55 to +125 C Storage Temperature T STG 55 to C Electrical Characteristics Parameter Symbol Conditions Minimum Typical Maximum Units Reverse Stand-Off oltage WM R. 3 3 Punch-Through Snap-Back oltage oltage PT SB I PT I SB = 2µ 3. 5 = 5m 2. 8 Reverse Leakage Current I R RWM = 3.3, T=25 C. 5 µ Clamping oltage C = 1, tp = 8/2µ s ny I/O to Gnd Clamping oltage C = 5, tp = 8/2µ s ny I/O to Gnd Clamping oltage C =, tp = 8/2µ s ny I/O to Gnd Steering Diode Forward oltage (Reverse Clamping oltage) F = 1, tp = 8/2µ s Gnd to ny I/O 1.7 Junction Capacitance C j R =, f = 1MHz 4 pf 26 Semtech Corp. 2

3 Non-Repetitive Peak Pulse Power vs. Pulse Time Power Derating Peak Pulse Power - P PP (kw) Pulse Duration - tp (Ξs) Pulse Waveform % of Rated Power or mbient Temperature - T ( o C) Clamping oltage vs. Peak Pulse Current Percent of e -t td = /2 Waveform Parameters: tr = 8µs td = 2µs Time (µs) Reverse Clamping oltage - c () Waveform Parameters: tr = 8µs td = 2µs Peak Pulse Current - I pp () Normalized Capacitance vs. Rever erse oltage CJ(R) / CJ(R=) Reverse oltage - R () f = 1 MHz 26 Semtech Corp. 3

4 pplications Information Device Connection for Protection of Four Data Lines The SMS3.3 is designed to protect up to four unidirectional data lines. The device is connected as follows: SMS3.3 Circuit Diagram 1. Unidirectional protection of four I/O lines is achieved by connecting pins 1, 3, 4 and 6 to the data lines. Pin 2 and 5 are connected to ground. The ground connections should be made directly to the ground plane for best results. The path length is kept as short as possible to reduce the effects of parasitic inductance in the board traces. Circuit Board Layout Recommendations for Suppression of ESD Good circuit board layout is critical for the suppression of ESD induced transients. The following guidelines are recommended: Protection of Four Unidirectional Lines Place the TS near the input terminals or connectors to restrict transient coupling. Minimize the path length between the TS and the protected line. Minimize all conductive loops including power and ground loops. The ESD transient return path to ground should be kept as short as possible. Never run critical signals near board edges. Use ground planes whenever possible. Matte Tin Lead Finish Matte tin has become the industry standard lead-free replacement for SnPb lead finishes. matte tin finish is composed of % tin solder with large grains. Since the solder volume on the leads is small compared to the solder paste volume that is placed on the land pattern of the PCB, the reflow profile will be determined by the requirements of the solder paste. Therefore, these devices are compatible with both lead-free and SnPb assembly techniques. In addition, unlike other lead-free compositions, matte tin does not have any added alloys that can cause degradation of the solder joint. 26 Semtech Corp. 4

5 Typical pplications 26 Semtech Corp. 5

6 Outline Drawing -- SOT23 SO-8 6L 2X E/2 ccc C 2X N/2 TIPS aaa C SETING PLNE C N 1 2 B D e1 D EI E e 2 1 bxn bbb C -B D H GGE PLNE.25 H SIDE IEW DETIL L (L1) c 1 SEE DETIL DIMENSIONS INCHES MILLIMETERS DIM MIN NOM MX MIN NOM MX b c D E E e.1 BSC.37 BSC 2.8 BSC.95 BSC e1.75 BSC 1.9 BSC L L1 (.24) (.6) N aaa.4. bbb.8.2 ccc.8.2 NOTES: 1. CONTROLLING DIMENSIONS RE IN MILLIMETERS (NGLES IN DEGREES). 2. DTUMS -- ND -B- TO BE DETERMINED T DTUM PLNE -H- 3. DIMENSIONS "E1" ND "D" DO NOT INCLUDE MOLD FLSH, PROTRUSIONS OR GTE BURRS. Land Pattern - SOT23 6L X (C) G Y Z DIM C G P X Y Z DIMENSIONS INCHES MILLIMETERS (.98) (2.5) P NOTES: 1. THIS LND PTTERN IS FOR REFERENCE PURPOSES ONLY. CONSULT YOUR MNUFCTURING GROUP TO ENSURE YOUR COMPNY'S MNUFCTURING GUIDELINES RE MET. 26 Semtech Corp. 6

7 Marking Ordering Information Part Number Lead Finish Qty per Reel Reel Size SMS3.3.TCT Pb free 3, 7 Inch Top Side Mark Tape and Reel Specification Device Orientation in Tape: Direction of Feed Tape Specifications (per EI 481) Reel Material: Static Dissipative Tape Material: Static Dissipative Tape Width: 8mm +/-.3mm Component Pitch (max.): 4mm +/-.mm Component Cavity Play: 2 Contact Information Semtech Corporation Protection Products Division 2 Flynn Rd., Camarillo, C 9312 Phone: (85) FX (85) Semtech Corp. 7