SM14LCV1.7C

TITE SCOTTSDALE DIVISION LAMP SM14LV1.7C TVSarray™ FEATURES • • • • • ULTRA LOW CLAMP FOR SENSITIVE I/O PORTS Clamps voltage to 1.7V max above signal level Operates over range from 3V through 30V Protects 10 lines uni and bi-directional to voltage bus UL 94V-O Flammability Classification T I T E Clamp™ T V S S E R I E S W W W . Microsemi . C O M APPLICATIONS • • • • RS-232-B RS-422-A RS-423-A RS-485 SO-14 Package MAXIMUM RATINGS • • • • • • • • Operating Temperature: -55°C to +50°C Storage Temperature: -55°C to +125°C Forward Surge Current: 8A (6/70µs) Minimum Reverse Breakdown Voltage ( VBR): 35V Working Peak Reverse Voltage VRWM to 30V Continuous forward current, IF: 400mA Power dissipation, (PD): 500mW Derating factor: 4.0 mW/°C Device Pin Out Configuration PACKAGING • • • Tape & Reel per EIA Standard 481 2,500 pieces per 13 inch reel (STANDARD) Carrier tube 50 pcs (OPTIONAL) • • • • MECHANICAL Molded SOIC 14 PIN Surface Mount Weight 2.5 grams (approximate) Marking: Logo, Date Code Pin 1 defined by dot ELECTRICAL CHARACTERISTICS PER LINE @ 25°C Unless otherwise specified VBR @100µA VOLTS MIN SM14LCV1.7C LV1.7C 35 VRWM VOLTS MAX 30 MAX 200* IR +25°c A @V R 30 IR +50°c A @V R 20 CAP @ 3V pF TYP 45 CAP @10V pF TYP 30 CAP @15V pF TYP 27 VF @ IF 100mA VOLTS MAX 0.5 VF(surge) @ IPP = 8 A 6/70 µs VOLTS MAX 1.70 PART NUMBER DEVICE MARKING MAX 500* * These values of leakage current IR represent multiple diodes as a result of their common anode or cathode connections. SM14LV1.7C OUTLINE DIM A B C E F G H J K INCHES MIN MAX 0.336 0.344 0.150 0.158 0.228 0.244 0.011 0.021 0.004 0.010 0.053 0.069 0.006 0.010 0.189 0.206 0.016 0.050 MILLIMETERS MIN MAX 8.53 8.74 3.81 4.01 5.79 6.19 0.28 0.53 0.10 0.20 1.35 1.75 0.15 0.25 4.80 5.23 0.41 1.27 Copyright  2001 MSCXXXX.PDF 9-20-2004 REV J Microsemi Scottsdale Division 8700 E. Thomas Rd. PO Box 1390, Scottsdale, AZ 85252 USA, (480) 941-6300, Fax: (480) 947-1503 TITE SCOTTSDALE DIVISION LAMP SM14LV1.7C TVSarray™ Application Notes For Using The SM14LV1.7C TITEClampTM TVSarrayTM The SM14LV1.7C TITEClamp TVSarray is a 10 wire protector designed for clamping voltage spikes to lowest possible levels between the signal line and the Vcc supply or ground. This device incorporates Microsemi's proprietary "Self Programmable" feature that provides exceedingly tight clamping of only 1.7V maximum above signal line voltages ranging from 3.0V up through 30V. Destructive over-current is diverted through the plus and minus Vcc rails or ground for negative transients. One size fits all Downsizing of on chip components to sub-micron dimensions has improved performance, reduced component size and cost at the expense of lower failure voltage thresholds. The demand has surfaced for improved protection across data lines in highly automated manufacturing, monitoring and control systems. These environments are usually harsh and subject to conducted and induced transient voltages originating from sources including motors, solenoids and welders. The connection points are shown in figure 1. Pins 1 and 14 are connected to +Vcc, with pins 7 & 8 being either -Vcc or ground. The lines are spread out for purposes of illustrating the connections; however, the traces between signal lines and the TVS should be at an absolute minimum to reduce parasitic reluctance which causes overshoot per Faraday's laws of induction, V=L(di/dt). In figure 2, the segment for a single wire is detailed for improved illustration. A scaled illustration of clamping on a 12V signal line example is shown in figure 3. This depicts a small but acceptable rise in voltage above the signal during worse case transient conditions. W W W . Microsemi . C O M + Vcc Clamp Level 12 V Si gnal Volt age 1.7V M ax 2 4 1 3 5 To Si gnal Line V + VCC 1 2 3 4 5 6 7 14 13 12 TITE - Vcc or Gnd t LAMP 11 10 9 8 Single Line Detail Clamp Performance 7 9 6 8 10 - VCC or Gnd Figure 2. Figure 3. Line Installation SM14LV1.7C Figure 1. Precautions in component placement and board layout: 1. Place the SM14LV1.7C directly at the board/signal line interface. 2. Keep all traces short for both signal lines and Vcc (and ground if applicable). 3. Eliminate ground loops. If the reader has further technical questions, please contact Microsemi-Scottsdale applications engineering at 480-941-6433 or 480-941-6524. Copyright  2001 MSCXXXX.PDF 9-20-2004 REV J Microsemi Scottsdale Division 8700 E. Thomas Rd. PO Box 1390, Scottsdale, AZ 85252 USA, (480) 941-6300, Fax: (480) 947-1503