EClamp2378P. ESD/EMI Protection for Color LCD Interfaces PRELIMINARY. PROTECTION PRODUCTS - EMIClamp TM Description. Features

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1 - EMIlamp TM Description The Elamp TM 2378P is a low pass filter array with integrated TVS diodes. It is designed to suppress unwanted EMI/RFI signals and provide electrostatic discharge (ESD) protection in portable electronic equipment. This state-of-the-art device utilizes solidstate silicon-avalanche technology for superior clamping performance and D electrical characteristics. They have been optimized for protection of color LD panels in cellular phones and other portable electronics. The device consists of eight identical circuits comprised of TVS diodes for ESD protection, and a resistor - capacitor network for EMI/RFI filtering. A series resistor value of 00Ω and a capacitance value of 0pF are used to achieve 30dB minimum attenuation from.8 to 2.5. The TVS diodes provide effective suppression of ESD voltages in excess of ±5kV (air discharge) and ±8kV (contact discharge) per IE , level 4. The Elamp2378P is in a 6-pin, RoHS/WEEE compliant, SLP406P6 package. It measures 4.0 x.6 x 0.58mm. The leads are spaced at a pitch of 0.5mm and are finished with lead-free NiPd. The small package makes it ideal for use in portable electronics such as cell phones, digital still cameras, and PDAs. ircuit Diagram (Each Line) Features Package onfiguration Elamp2378P ESD/EMI Protection for olor LD Interfaces Bidirectional EMI/RFI filter with integrated TVS for ESD protection ESD protection to IE (ESD) Level 4, ±5kV (air), ±8kV (contact) Filter performance: 30dB minimum attenuation.8 to 2.5 TVS working voltage: 5V Resistor: 00Ω +/ 5% Typical apacitance: 20pF (VR = 0V) Protection and filtering for eight lines Solid-state technology Mechanical haracteristics SLP406P6 6-pin package RoHS/WEEE ompliant Nominal Dimensions: 4.0 x.6 x 0.58 mm Lead Pitch: 0.5mm Lead finish: NiPdAu Marking : Marking ode Packaging : Tape and Reel Applications olor LD Protection ell Phone D amera Lines lamshell ell Phones IN 00 Ω 0pF 0pF OUT BS GND 0.58 Revision 0/26/2007 Device Schematic (8X) 6 Pin SLP package (Bottom Side View) Nominal Dimensions in mm

2 Maximum Ratings Rating Symbol Value Units ESD per IE (Air) ESD per IE (ontact) +/- 7 V ESD +/- 2 kv Junction Temperature T J 25 o Operating Storage Temperature Temperature T op 40 to +85 T STG 55 to o - o Electrical haracteristics (T = 25 o ) P arameter r S ymbo l ondition s M inimu m T ypica l M aximu m Unit s TVS Reverse Stand-Off Voltage V RWM 5 V TVS Reverse Breakdown Voltage V R B I t = ma V TVS Reverse Leakage urrent I R V RWM = 3.0V 0. 5 µ A Total Series Resistance R Each Line Ohms Total Total apacitance apacitance i n Input to Gnd, V R Each Line = 0V, f = i n Input to Gnd, V R Each Line = 2.5V, f = pf 9 3 pf 2007 Semtech orp. 2

3 Typical haracteristics Typical Insertion Loss S2 (Each Line) Analog rosstalk (Each Line) H S2 LOG 6 db / REF 0 db : db H S2 LOG 20 db / REF 0 db 0 db -6 db -2 db -8 db 2: db 900 3: db.8 4: db db 2-30 db db -42 db -48 db START. 030 STOP START. 030 STOP ESD lamping (+8kV ontact per IE ) ESD lamping (-8kV ontact per IE ) Note: Data is taken with a 0x attenuator Note: Data is taken with a 0x attenuator Normalized apacitance vs. Reverse Voltage J (V R ) / J (V R =0) f = Reverse Voltage - V R (V) 2007 Semtech orp. 3

4 Applications Information Device onnection The Elamp2378P is comprised of eight identical circuits each consisting of a low pass filter for EMI/RFI suppression and dual TVS diodes for ESD protection. The device is in a 6-pin SLP package. Electrical connection is made to the 6 pins located at the bottom of the device. A center tab serves as the ground connection. The device has a flow through design for easy layout. Pin connections are noted in Figure. All path lengths should be kept as short as possible to minimize the effects of parasitic inductance in the board traces. Recommendations for the ground connection are given below. Ground onnection Recommendation Parasitic inductance present in the board layout will affect the filtering performance of the device. As frequency increases, the effect of the inductance becomes more dominant. This effect is given by Equation. Equation : The Impedance of an Inductor at Frequency XLF XLF(L,f ) = 2 * π * f * L Where: L= Inductance (H) f = Frequency (Hz) Via connections to the ground plane form rectangular wire loops or ground loop inductance as shown in Figure 2. Ground loop inductance can be reduced by using multiple vias to make the connection to the ground plane. Bringing the ground plane closer to the signal layer (preferably the next layer) also reduces ground loop inductance. Multiple vias in the device ground pad will result in a lower inductive ground loop over two exterior vias. Vias with a diameter d are separated by a distance y run between layers separated by a distance x. The inductance of the loop path is given by Equation 2. Thus, decreasing distance x and y will reduce the loop inductance and result in better high frequency filter characteristics. Figure - Pin Identification and onfiguration (Top Side View) Pin Identification - 8 Input Lines 9-6 Output Lines enter In In 2 In 3 In 4 In 5 In 6 In 7 In 8 Tab Gnd Out Out 2 Out 3 Out 4 Out 5 Out 6 Out 7 Out 8 Ground Figure 2 - Inductance of Rectangular Wire Loops Ground Via x y Ground Via 2 d Signal Layer Ground Layer Layer Equation 2: Inductance of Rectangular Wire Loop 2*y 2*x [ x *ln[ ] y *ln[ ] 9 LRET (d, x, y) = 0.6 *0 * + d Where: d = Diameter of the wire (in) x = Length of wire loop (in) y = Breath of wire loop (in) d 2007 Semtech orp. 4

5 Applications Information Figure 3 shows the recommended device layout. The ground pad vias have a diameter of inches (0.20 mm) while the two external vias have a diameter of 0.00 inches (0.250mm). The internal vias are spaced approximately evenly from the center of the pad. The designer may choose to use more vias with a smaller diameter (such as inches or 0.25mm) since changing the diameter of the via will result in little change in inductance (i.e. the log function in Equation 2 in highly insensitive to parameter d). Figure 4 shows a typical insertion loss (S2) plot for the device using Semtech s filter evaluation board with 50 Ohm traces and the recommended via configuration. Figure 5 shows a typical insertion loss (S2) plot using a similar board without the internal ground pad vias. The result is a more inductive ground loop. Note the hump at a frequency of 2.5. This is the resonant frequency of the higher ground loop inductance. Figure 4 - Filter haracteristics Using Recommended Layout with Internal Vias 0 db -6 db -2 db -8 db -24 db -30 db -36 db -42 db -48 db H S2 LOG 6 db / REF 0 db : db : db 900 3: db.8 4: db 2.5 START. 030 STOP Figure 3 - Recommended Layout Using Ground Vias Figure 5 - Filter haracteristics Using Layout without Internal Ground Vias H S2 LOG 6 db / REF 0 db : db : db 900 3: db.8 0 db -6 db 4: db db 4-8 db -24 db db -36 db START. 030 STOP Semtech orp. 5

6 Applications Information - Spice Model Line In.4nH.4nH Line Out Elamp2378P Spice Model Elamp2378P Spice Parameters Parameter IS BV VJ RS IBV JO TT U nit D (TVS) D2 (TVS) Amp 2E-5 2E-5 Volt Volt Ohm Farad 9.8E-2 9.8E-2 Amp E-3 E-3 sec 2.54E E- 9 M N --.. EG ev Semtech orp. 6

7 Outline Drawing - SLP406P6 A PIN INDIATOR (LASER MARK) aaa A2 2 D D B E A A SEATING PLANE DIMENSIONS INHES MILLIMETERS DIM MIN NOM MAX MIN NOM MAX A A A2 (.005) (0.3) b D D E E e BS 0.50 BS L N aaa bbb LxN E/2 E e N D/2 bxn bbb A B NOTES:. ONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). 2. OPLANARITY APPLIES TO THE EXPOSED PAD AS WELL AS THE TERMINALS. Land Pattern - SLP406P6 P Z G Y X F () DIMENSIONS DIM INHES MILLIMETERS B F G P X Y Z B NOTES:. THIS LAND PATTERN IS FOR REFERENE PURPOSES ONLY. ONSULT YOUR MANUFATURING GROUP TO ENSURE YOUR OMPANY'S MANUFATURING GUIDELINES ARE MET 2007 Semtech orp. 7

8 Marking Ordering Information PIN INDIATOR (LASER MARK) 2378P Part Number Qty per Reel Reel Size Elamp2378P.TT Inch EMIlamp and Elamp are marks of Semtech orporation Tape and Reel Specification Pin Location User Direction of feed Device Orientation in Tape A0 B0 K0.78 +/-0.0 mm /-0.0 mm /-0.0 mm Tape Width B, (Max) D D E F K (MAX) P P0 P 2 T(MAX) W 2 mm 8.2 mm (.476) mm mm ( ).0 mm ±0.05 (.039).750±.0 mm (.069±.004) 5.5±0.05 mm (.27±.002) 4.5 mm (.77) 4.0±0. mm (.57±.00-4) 4.0±0. mm (.57±.00-4) 2.0±0.05mm (.079±.002) 0.4 mm (.06) 2.0 mm mm - 0. mm (.472±.02) ontact Information Semtech orporation Protection Products Division 200 Flynn Rd., amarillo, A 9302 Phone: (805)498-2 FAX (805) Semtech orp. 8