SLVE2.8 & SLVG2.8 ™ Diodes For EPD TVS™ ESD and Latch-Up Protection PROTECTION PRODUCTS Description Features The SLV series of transient voltage suppressors are designed to protect low voltage, state-of-the-art CMOS semiconductors from transients caused by electrostatic discharge (ESD), cable discharge events (CDE), lightning and other induced voltage surges. ! 300 Watts peak pulse power (tp = 8/20µs) ! Transient protection for low voltage data lines to The devices are constructed using Semtech’s proprietary EPD process technology. The EPD process provides low standoff voltages with significant reductions in leakage currents and capacitance over siliconavalanche diode processes. The SLVE2.8 & SLVG2.8 are in a SOT-143 package and have a low 2.8V working voltage. They may be used to protect one line in differential or common mode. The “flow-thru” design minimizes trace inductance and reduces voltage overshoot associated with ESD events. ! ! ! ! ! ! IEC 61000-4-2 (ESD) 15kV (air), 8kV (contact) IEC 61000-4-4 (EFT) 40A (tp = 5/50ns) IEC 61000-4-5 (Lightning) 24A (tp = 8/20µs) Protects one line Comprehensive pin out for easy board layout Low capacitance Low leakage current Low operating and clamping voltages Solid-state EPD TVS process technology Mechanical Characteristics ! ! ! ! The SLV is specifically designed to protect low voltage components such as Ethernet transceivers, laser diodes, ASICs, and high-speed RAM. The low clamping voltage of the SLV minimizes the stress on the protected IC. JEDEC SOT-143 package Molding compound flammability rating: UL 94V-0 Marking : Marking code Packaging : Tape and Reel per EIA 481 Applications ! ! ! ! ! ! ! ! The SLV series TVS diodes will exceed the surge requirements of IEC 61000-4-2, Level 4. Schematic & Pin Configuration ESD and Latch-up Protection Analog Inputs WAN/LAN Equipment Low Voltage ASICs Desktops, Servers, Notebooks & Handhelds Portable Instrumentation Base Stations Laser Diode Protection Schematic & PIN Configuration 4 4 1 2 1 3 2 SLVG2.8 (Top View) Revision 1/18/2001 3 SLVE2.8 (Top View) 1 www.semtech.com SLVE2.8 & SLVG2.8 PROTECTION PRODUCTS Absolute Maximum Rating R ating Symbol Value Units Peak Pulse Power (tp = 8/20µs) Pp k 300 Watts Peak Pulse Current (tp = 8/20µs) IP P 24 A 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 SLVE2.8 Parameter Reverse Stand-Off Voltage Symbol Conditions Minimum Typical VRWM Maximum Units 2.8 V Punch-Through Voltage V PT IPT = 2µA 3.0 V Snap-Back Voltage VSB ISB = 50mA 2.8 V Reverse Leakage Current IR VRWM = 2.8V, T=25°C 1 µA Clamping Voltage VC IPP = 1A, tp = 8/20µs 4.1 V Clamping Voltage VC IPP = 5A, tp = 8/20µs 5.3 V Clamping Voltage VC IPP = 24A, tp = 8/20µs 15 V Junction Capacitance Cj Line-to-Line VR = 0V, f = 1MHz 100 pF Symbol Conditions Maximum Units 2.8 V SLVG2.8 Parameter Reverse Stand-Off Voltage Minimum VRWM Typical Punch-Through Voltage V PT IPT = 2µA 3.0 V Snap-Back Voltage VSB ISB = 50mA 2.8 V Reverse Leakage Current IR VRWM = 2.8V, T=25°C 1 µA Clamping Voltage VC IPP = 1A, tp = 8/20µs 4.1 V Clamping Voltage VC IPP = 5A, tp = 8/20µs 5.3 V Clamping Voltage VC IPP = 24A, tp = 8/20µs 15 V Junction Capacitance Cj Line-to-Line VR = 0V, f = 1MHz 50 pF 2001 Semtech Corp. 2 www.semtech.com SLVE2.8 & SLVG2.8 PROTECTION PRODUCTS Typical Characteristics Non-Repetitive Peak Pulse Power vs. Pulse Time Power Derating Curve 110 10 90 % of Rated Power or IPP Peak Pulse Power - PPP (kW) 100 1 0.1 80 70 60 50 40 30 20 10 0 0.01 0.1 1 10 100 0 1000 25 Pulse Duration - tp (µ µs) 75 100 125 150 o Pulse Waveform Clamping Voltage vs. Peak Pulse Current 110 18 Waveform Parameters: tr = 8µs td = 20µs 90 80 70 16 Clamping Voltage - VC (V) 100 Percent of IPP 50 Ambient Temperature - TA ( C) -t e 60 50 40 td = IPP/2 30 20 SLVG2.8 14 12 10 SLVE2.8 8 6 Waveform Parameters: tr = 8µs td = 20µs 4 2 10 0 0 0 5 10 15 20 25 30 0 Time (µ µs) 2001 Semtech Corp. 5 10 15 20 25 30 35 Peak Pulse Current - IPP (A) 3 www.semtech.com SLVE2.8 & SLVG2.8 PROTECTION PRODUCTS Applications Information Circuit Diagrams Device Connection Electronic equipment is susceptible to transient disturbances from a variety of sources including: ESD to an open connector or interface, direct or nearby lightning strikes to cables and wires, and charged cables “hot plugged” into I/O ports. The SLV series is designed to protect sensitive components from damage and latchup which may result from such transient events. The SLVG2.8 is designed to protect one unidirectional line while the SLVE2.8 is designed to protect one bidirectional line (or two differential lines). The options for connecting the devices are as follows: " " 1 3 2 3 2 SLVG2.8 SLVE2.8: Common mode protection of one bidirectional data line is achieved by connecting the data line input/output at pins 2 and 3. Pins 1 and 4 are connected to ground. For differential protection, pins 1 & 4 can be connected to a second I/O line. For best results, the ground connection should be made directly to a ground plane on the board. The path length should be kept as short as possible to minimize parasitic inductance. SLVG2.8: Common mode protection of one unidirectional line is achieved by connecting the line to be protected at pins 2 & 3. Pins 1 & 4 are connected to ground. For best results, the ground connection should be made directly to a ground plane on the board. The path length should be kept as short as possible to minimize parasitic inductance. SLVE2.8 Common Mode Protection (SLVE2.8 & SLVG2.8) 4 1 Line In Circuit Board Layout Recommendations for Suppression of ESD. 2 3 Line Out Differential Mode Protection (SLVE2.8 only) Good circuit board layout is critical for the suppression of ESD induced transients. The following guidelines are recommended: " Place the TVS near the input terminals or connectors to restrict transient coupling. " Minimize the path length between the TVS 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. 2001 Semtech Corp. 4 4 1 Line 1 In Line 2 In 4 4 1 2 3 Line 1 Out Line 2 Out www.semtech.com SLVE2.8 & SLVG2.8 PROTECTION PRODUCTS Applications Information (continued) EPD TVS™ Characteristics I PP The SLV series is constructed using Semtech’s proprietary EPD technology. The structure of the EPD TVS is vastly different from the traditional pn-junction devices. At voltages below 5V, high leakage current and junction capacitance render conventional avalanche technology impractical for most applications. However, by utilizing the EPD technology, the SLVE2.8 & SLVG2.8 can effectively operate at 2.8V while maintaining excellent electrical characteristics. I SB I PT VBRR IR VRWM VSB VPT VC I BRR The EPD TVS employs a complex nppn structure in contrast to the pn structure normally found in traditional silicon-avalanche TVS diodes. The EPD mechanism is achieved by engineering the center region of the device such that the reverse biased junction does not avalanche, but will “punch-through” to a conducting state. This structure results in a device with superior dc electrical parameters at low voltages while maintaining the capability to absorb high transient currents. EPD TVS VI Characteristic Curve The IV characteristic curve of the EPD device is shown in Figure 1. The device represents a high impedance to the circuit up to the working voltage (VRWM). During a transient event, the device will begin to conduct as it is biased in the reverse direction. When the punchthrough voltage (VPT) is exceeded, the device enters a low impedance state, diverting the transient current away from the protected circuit. When the device is conducting current, it will exhibit a slight “snap-back” or negative resistance characteristic due to its structure. This must be considered when connecting the device to a power supply rail. To return to a non-conducting state, the current through the device must fall below the snap-back current (approximately < 50mA). 2001 Semtech Corp. 5 www.semtech.com SLVE2.8 & SLVG2.8 PROTECTION PRODUCTS Outline Drawing - SOT-143 Notes: (1) Controlling dimension: Millimeters. (2) Dimension A and B do not include mold protrusions. Mold protrusions are .006” max. Land Pattern - SOT-143 2001 Semtech Corp. 6 www.semtech.com SLVE2.8 & SLVG2.8 PROTECTION PRODUCTS Marking Codes Part Number Marking Code SLVE2.8 E2.8 SLVG2.8 G2.8 Ordering Information Part Number Working Voltage Qty per R eel R eel Size SLVE2.8.TC 2.8V 3,000 7 Inch SLVG2.8.TC 2.8V 3,000 7 Inch Note: Consult factory for availability of 13” reels 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