ESDA25B1

® ESDA25B1 TRANSIL™ ARRAY FOR ESD PROTECTION Application Specific Discretes A.S.D.™ APPLICATIONS Where transient overvoltage protection in ESD sensitive equipment is required, such as : - COMPUTER - PRINTERS - COMMUNICATION SYSTEMS It is particulary recommended for RS232 I/O port protection where the line interface withstands only 2 kV ESD surges. FEATURES 6 BIDIRECTIONALTRANSIL™ FUNCTIONS VERY LOW CAPACITANCE : C= 20 pF @ VRM 150 W peak pulse power (8/20 µs) DESCRIPTION The ESDA25B1 is a monolithic voltage suppressor designed to protect components which are connected to data and transmission lines against EDS. SO-8 FUNCTIONAL DIAGRAM I/O 1 BENEFITS High ESD protection level : up to 25 kV High integration Suitable for high density boards 1 2 3 4 8 7 6 5 I/O 6 I/O 5 I/O 4 GND I/O 2 I/O 3 GND COMPLIESWITH THE FOLLOWING STANDARDS : IEC 1000-4-2 : level 4 MIL STD 883C-Method 3015-6 : class 3 (human body model) October 1999 - Ed : 2 1/5 ESDA25B1 ABSOLUTE MAXIMUM RATINGS (Tamb = 25°C) Symbol VPP PPP Tstg Tj TL Parameter Electrostatic discharge MIL STD 883C - Method 3015-6 Peak pulse power (8/20µs) Storage temperature range Maximum junction temperature Maximum lead temperature for soldering during 10s Value 25 150 - 55 to + 150 125 260 Unit kV W °C °C °C ELECTRICAL CHARACTERISTICS (Tamb = 25°C) Symbol VRM VBR VCL IRM IPP Parameter Stand-off voltage Breakdown voltage Clamping voltage Leakage current Peak pulse current Voltage temperature coefficient Capacitance Dynamic resistance αT C Rd Types VBR min. note 1 V @ max. IR IRM max. note 1 µA 2 @ VRM Rd typ. note 2 Ω 1.5 αT max. note 3 10-4/°C 9.7 C typ. 0V bias pF 15 V 30 mA 1 V 24 ESDA25B1 25 note 1 : Between any I/O pin and Groung note 2 : Square pulse, Ipp = 25A, tp=2.5 µs. note 3 : ∆ VBR = αT* (Tamb -25°C) * VBR (25°C) 2/5 ESDA25B1 CALCULATION OF THE CLAMPING VOLTAGE USE OF THE DYNAMIC RESISTANCE The ESDA family has been designed to clamp fast spikes like ESD. Generally the PCB designers need to calculate easily the clamping voltage VCL. This is why we give the dynamic resistance in addition to the classical parameters. The voltage across the protection cell can be calculated with the following formula: VCL = VBR + Rd IPP WhereIpp is the peakcurrent throughthe ESDAcell. DYNAMIC RESISTANCE MEASUREMENT The short duration of the ESD has led us to prefer a more adapted test wave, as below defined, to the classical 8/20µs and 10/1000µs surges. I Ipp As the value of the dynamic resistance remains stable for a surge duration lower than 20µs, the 2.5µs rectangular surge is well adapted. In addition both rise and fall times are optimized to avoid any parasitic phenomenon during the measurement of Rd. 2µs tp = 2.5µs t 2.5µs duration measurement wave. 3/5 ESDA25B1 Fig. 1 : Peak power dissipation versus initial junction temperature. Ppp[Tj initial]/Ppp[Tj initial=25 °C] 1.1 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 2000 1000 Fig. 2 : Peak pulse power versus exponential pulse duration (Tj initial = 25 °C). Ppp(W) 100 Tj initial(°C) 0 25 50 75 100 125 150 10 1 tp(µs) 10 100 Fig. 3 : Clamping voltage versus peak pulse current (Tj initial = 25 °C). Rectangular waveform tp = 2.5 µs. Ipp(A) 50.0 tp=2.5µs Fig. 4 : Capacitance versus reverse applied voltage (typical values). C(pF) 20 10 5 F=1MHz Vosc=30mV 10.0 1.0 2 V CL(V) 0.1 20 25 30 35 40 45 50 55 60 VR(V) 1 1 2 5 10 30 Fig. 5 : Relative variation of leakage current versus junction temperature (typical values). IR[Tj] / IR[Tj=25°C] 200 100 10 Tj(°C) 1 25 50 75 100 125 4/5 ESDA25B1 ORDER CODE ESDA 25 B 1 RL ESD ARRAY VBR min Bidirectionel PACKAGING: RL = Tape and reel = Tube PACKAGE : SO-8 MARKING : Logo, Date Code, E25B1 PACKAGE MECHANICAL DATA SO-8 Plastic REF. A a1 a2 a3 b b1 C c1 D E e e3 F L M S Packaging : Preferred packaging is tape and reel. Weight : 0.08g. Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringementof patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics. DIMENSIONS Millimeters Inches Min. 0.1 0.65 0.35 0.19 0.25 4.8 5.8 1.27 3.81 3.8 0.4 4.0 0.15 1.27 0.016 0.6 8° (max) Typ. Max. Min. 1.75 0.25 0.004 1.65 0.85 0.026 0.48 0.014 0.25 0.007 0.5 0.010 45° (typ) 5.0 0.189 6.2 0.228 0.050 0.150 0.157 0.050 0.024 Typ. Max. 0.069 0.010 0.065 0.033 0.019 0.010 0.020 0.197 0.244 The ST logo is a registered trademark of STMicroelectronics © 1999 STMicroelectronics - Printed in Italy - All rights reserved. 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