SMF3.3 3.3 Volt TVS Array For ESD and Latch-Up Protection PROTECTION PRODUCTS Description PRELIMINARY Features The SMF series of TVS 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. ESD protection for data lines to The SMF3.3 is a solid-state devices designed specifically for transient suppression. It is 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. Mechanical Characteristics EIAJ SC70-5L package Molding compound flammability rating: UL 94V-0 Marking : Marking Code Packaging : Tape and Reel per EIA 481 Applications The SMF3.3 may be used to meet the immunity requirements of IEC 61000-4-2, level 4 (15kV air, 8kV contact discharge). The small SC70-5L package makes them ideal for use in portable electronics such as cell phones, PDA’s, and notebook computers. Circuit Diagram 1 IEC 61000-4-2 (ESD) 15kV (air), 8kV (contact) Small package for use in portable electronics Protects four I/O lines Working voltage: 3.3V Low leakage current Low operating and clamping voltages Solid-state EPD TVS technology Cellular Handsets & Accessories Cordless Phones Personal Digital Assistants (PDA’s) Notebooks & Handhelds Portable Instrumentation Digital Cameras Peripherals MP3 Players Schematic & PIN Configuration 3 4 5 1 5 2 3 4 2 SC70-5L (Top View) Revision 02/07/2002 1 www.semtech.com SMF3.3 PRELIMINARY PROTECTION PRODUCTS Absolute Maximum Rating R ating Symbol Value Units Peak Pulse Power (tp = 8/20µs) Pp k 100 Watts Peak Pulse Current (tp = 8/20µs) IP P 5 A ESD per IEC 61000-4-2 (Air) ESD per IEC 61000-4-2 (Contact) VESD 20 15 kV Lead Soldering Temperature TL 260 (10 seconds) o Operating Temperature TJ -55 to +125 o TSTG -55 to +150 o Storage Temperature C C C Electrical Characteristics SMF3.3 Parameter Reverse Stand-Off Voltage Symbol Conditions Minimum Typical VRWM Maximum Units 3.3 V Punch-Through Voltage V PT IPT = 2µA 3.5 V Snap-Back Voltage VSB ISB = 50mA 2.8 V Reverse Leakage Current IR VRWM = 3.3V, T=25°C Clamping Voltage VC Clamping Voltage 0.5 µA IPP = 1A, tp = 8/20µs 5.5 V VC IPP = 5A, tp = 8/20µs 8.0 V Reverse Clamping Voltage VCR IPP = 1A, tp = 8/20µs 2.4 V Junction Capacitance Cj Each I/O pin and Gnd VR = 0V, f = 1MHz 2001 Semtech Corp. 2 0.05 25 pF www.semtech.com SMF3.3 PRELIMINARY PROTECTION PRODUCTS Typical Characteristics Non-Repetitive Peak Pulse Power vs. Pulse Time Power Derating Curve 110 10 100 % of Rated Power or IPP Peak Pulse Power - PPP (kW) 90 1 0.1 80 70 60 50 40 30 20 10 0 0.01 0.1 1 10 100 0 1000 25 50 75 100 125 150 o Ambient Temperature - TA ( C) Pulse Duration - tp (µs) Pulse Waveform Clamping Voltage vs. Peak Pulse Current 110 Waveform Parameters: tr = 8µs td = 20µs 100 90 70 8.00 Clamping Voltage - Vc (V Percent of IPP 80 10.00 -t e 60 50 40 td = IPP/2 30 20 10 6.00 4.00 Waveform Parameters: tr = 8µs td = 20µs 2.00 0 0 5 10 15 20 25 30 Time (µs) 0.00 0 1 2 3 4 5 6 7 Peak Pulse Current - Ipp (A) Forward Voltage vs. Forward Current Variation of Capaciatnce vs. Reverse Voltage 30 7.00 I/O to GND f = 1MHz 5.00 Capacitance - C (pF) Forward Voltage- Vf (V) 6.00 4.00 3.00 Waveform Parameters: tr = 8µs td = 20µs 2.00 1.00 0.00 L to G 20 L to L 10 0 0 1 2 3 4 5 6 0 7 2001 Semtech Corp. 1 2 3 Reverse Voltage - Vr (V) Forward Current - If (A) 3 www.semtech.com SMF3.3 PRELIMINARY PROTECTION PRODUCTS Applications Information SMF Circuit Diagram Device Connection for Protection of Four Data Lines The SMF3.3 is designed to protect up to four unidirectional data lines. The device is connected as follows: 1 3 4 5 1. Unidirectional protection of four I/O lines is achieved by connecting pins 1, 3, 4, and 5 to the data lines. Pin 2 is connected to ground. The ground connection 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. 2 Circuit Board Layout Recommendations for Suppression of ESD. Protection of Four Unidirectional Lines Good circuit board layout is critical for the suppression of ESD induced transients. The following guidelines are recommended: z Place the TVS near the input terminals or connectors to restrict transient coupling. z Minimize the path length between the TVS and the protected line. z Minimize all conductive loops including power and ground loops. z The ESD transient return path to ground should be kept as short as possible. z Never run critical signals near board edges. z Use ground planes whenever possible. 2001 Semtech Corp. 4 www.semtech.com SMF3.3 PRELIMINARY PROTECTION PRODUCTS Typical Applications SMF3.3 2001 Semtech Corp. 5 www.semtech.com SMF3.3 PRELIMINARY PROTECTION PRODUCTS Outline Drawing Land Pattern 2001 Semtech Corp. 6 www.semtech.com SMF3.3 PRELIMINARY PROTECTION PRODUCTS Marking Codes Part Number Marking Code SMF3.3 F03 Note: (1) Pin 1 Identified with a dot Ordering Information Part Number Working Voltage Qty per R eel R eel Size SMF3.3.TC 3.3V 3,000 7 Inch SMF3.3.TG 3.3V 10,000 13 Inch Contact Information Semtech Corporation Protection Products Division 652 Mitchell Rd., Newbury Park, CA 91320 Phone: (805)498-2111 FAX (805)498-3804 2001 Semtech Corp. 7 www.semtech.com