CLP30-200B1 ® Application Specific Discretes A.S.D™ OVERVOLTAGE & OVERCURRENT PROTECTION FOR TELECOM LINE MAIN APPLICATIONS Any telecom equipment submitted to transient overvoltages and lightning strikes such as : ■ Analog and ISDN line cards ■ PABX DESCRIPTION The CLP30-200B1 is designed to protect telecommunication equipment. It provides both a transient overvoltage protection and an overcurrent protection. The external components (balanced resistors, ring relays contact, ...) needed by the CLP30-200B1 protection concept require very low power rating. This results in a very cost effective protection solution. SO8 SCHEMATIC DIAGRAM (Top view) FEATURES ■ Dual bidirectional protection device. ■ High peak pulse current : IPP = 40A (5/310 µs SURGE) IPP = 30A (10/1000 µs SURGE) ■ Max. voltage at switching-on : 290V ■ Min. current at switching-off : 150mA BENEFITS ■ Voltage and current controlled suppression. ■ Surface Mounting with SO8 package. ■ Very low power rating of external components on line card : balanced resistors, ring relay, low voltage SLIC protection. July 1999 - Ed: 4 TIPL 1 TIPS GND GND GND GND RINGL RINGS 1/11 CLP30-200B1 Standard Peak surge Voltage voltage waveform (V) Required peak current (A) Current waveform Minimum serial resistor to meet standard ( ) Bellcore TR-NWT-1089 First level 2500 1000 2/10µs 10/100µs 500 100 2/10 µs 10/1000 µs 20 25 Bellcore TR-NWT-1089 Second level 5000 2/10 µs 500 2/10 µs 40 ITU-T-K20 / K21 4000 1000 10/700 µs 100 25 5/310 µs 50 0 ITU-T-K20 (IEC61000-4-2) 6000 8000 1/60 ns VDE0433 4000 2000 10/700 µs 100 50 5/310 µs 50 5 VDE0878 4000 2000 1.2/50 µs 100 50 1/20 µs 22 0 IEC61000-4-5 4000 2000 4000 10/700 µs 1.2/50 µs 1.2/50 µs 100 50 100 5/310 µs 8/20 µs 8/20 µs 50 0 22 FCC Part 68, lightning surge type A 1500 800 10/160 µs 10/560 µs 200 100 10/160 µs 10/560 µs 17.5 12 FCC Part 68, lightning surge type B 1000 9/720 µs 25 5/320 µs 0 ESD contact discharge ESD air discharge BLOCK DIAGRAM TIPL TIPS Overcurrent detector Overvoltage detector OR Overvoltage reference (> 200 V) SW1 GND SW2 Overvoltage detector OR Overcurrent detector RINGL 2/11 RINGS Overvoltage reference (> 200 V) 0 0 CLP30-200B1 Pin Symbol Description 1 TIPL TIP (Line side) 2/3/6/7 GND Ground 4 RINGL RING (Line side) 5 RINGS RING (SLIC side) 8 TIPS TIP (SLIC side) APPLICATION NOTE 1.INTRODUCTION 2. STMicroelectronics CLP30-200B1 CONCEPT The aim of this section is to show the behavior of our new telecom line protection device. Over the years, the performances of the SLICs considerably increased and therefore the need of the protection has also evolved. The CLP30-200B1 is especially designed for the protection of this new generation of SLIC. For this, it is based on both overvoltage and overcurrent protection modes. Fig.1 : Suscriber line protection topology "PRIMARY PROTECTION" "SECONDARY PROTECTION" telecommunication CLP30200B1 line MDF VOLTAGE REFERENCE 2.1 Evolution of the SLIC protection SLIC LINE CARD Fig.2 : Line card protection EXCHANGE I Figure 1 is a simplified block diagram of a subscriber line protection that is mainly used so far. This shows two different things : ■ A “primary protection” located on the Main Distribution Frame (MDF) eliminates coarsely the high energy environmental disturbances (lightning transients and AC power mains disturbances) for which the ITU-T-K20 requires a 4kV 10/700 µs test. This can be assumed either by gas-tubes or silicon protection such as the TLPxxM. ■ A “secondary protection” located on the line card eliminates finely the remaining transients that have not been totally suppressed by the first stage. The ITU-T-K20 requires a 1 kV 10/700 µs test. At this stage, the protection is managed by the CLP30-200B1. Programmable thanks to any external voltage reference Programmable thanks to an external resistor + I SWON - VSWON V + VSWON - I SWON Line Card operating conditions The figure 2 summarises the performance of the CLP30-200B1 which basically holds the SLIC inside its correct voltage and current values. 3/11 CLP30-200B1 APPLICATION CIRCUIT : CLP30-200B1 in line card Fig.3 : CLP30-200B1 in line card I PTC TIP R sense R TIPL -Vbat 1 TIPS Rp TIP Overcurrent detector 2 OR Overvoltage detector OR Overvoltage detector SW1 -Vbat Overvoltage reference (> 200 V) External voltage reference 1 GND SW2 Overvoltage reference (> 200 V) Rp 2 Overcurrent detector PTC RINGS RINGL R sense RING R Figure above shows the topology of a protected analog subscriber line at the line card side. ■ A first stage based on CLP30-200B1 manages the high power issued from the external surges. When used in ringing mode, the CLP30-200B1 operates in voltage mode and provides a symmetrical and bidirectional overvoltage protection above 200 V on both TIP and RING lines. When used in speech mode, the CLP30-200B1 operates in current mode and the activation current of the CLP30-200B1 is adjusted by RSENSE. ■ A second stage which is the external voltage reference device defines the firing threshold voltage during the speech mode and also assumes a residual power overvoltage suppression. This stage can be either a fixed or programmable device such as LCP1511D. 4/11 SLIC Ring Generator RING CLP30-200B1 2.3 Ringing mode Fig.4 : Switching by voltage during ringing mode. ILG ILG R sense TIP A1 TIPL 1 TIPS 1/2 CLP200M 2 Overcurrent detector 1 2 OR Overvoltage detector Overvoltage reference (>200V) -200 V LG +200 1 VLG SW1 3 GND In ringing mode (Ring relay in position 2), the only protection device involved is the CLP30-200B1. In normal conditions, the CLP30-200B1 operates in region 1 of A1 curve, and is idle. If an overvoltage occurring between TIP (or RING) and GND reaches the internal overvoltage reference (+/- 200V), the CLP30-200B1 acts and the line is short-circuited to GND. At this time the operating point moves to region 2 for positive surges (region 3 for negative surges). Once the surge current disappears, the device returns to its initial state (region 1). For surges occurring between TIP and RING, the CLP30-200B1 acts in the same way. This means that the CLP30-200B1 ensures a tripolar protection. When used alone, the CLP30-200B1 acts at the internal overvoltage reference level (+/- 200 V). Furthermore, it is possible to adjust this threshold level to a lower voltage by using up to 4 fixed external voltage reference (VZ1 to VZ4) (see fig.5). Fig.5 : Methode to adjust the reference voltage. 1 TIP R sense TIPL TIPS 2 VZ1 Overcurrent detector OR Overvoltage detector Overvoltage reference (>200V) Overvoltage detector Overvoltage reference (>200V) SW1 VZ2 GND SW2 OR VZ3 Overcurrent detector VZ4 RINGS RINGL RING 1 R sense 2 5/11 CLP30-200B1 2.4 Speech mode Fig.6 : Switching by current during speech mode. ILG ILG TIP R sense TIPL 1 TIPS Rp 6 -Vbat Overcurrent detector 2 OR Overvoltage detector Overvoltage reference (>200V) VLG External voltage reference -VBAT 4 VLG SW1 5 GND In speech mode (Ring relay in position 1), the protection is provided by the combination of both CLP30-200B1 and the external voltage reference device (for example LCP1511D). In normal conditions, the working point of this circuit is located in region 4 of A2 curve : the CLP30-200B1 is idle. When a surge occurs on the line, the external voltage reference device clamps at GND or -Vbat respectively for positive and negative surges. This generates a current which is detected by RSENSE and causes the protection to act : the line is short-circuited to GND. The operating point moves to region 6 for positive surges or region 5 for negative surges. 6/11 Once the surge current falls below the switching-off current ISWOFF, the CLP30-200B1 returns to its initial state (region 4). Furthermore, the CLP30-200B1 switches when an overvoltage, either positive or negative, occurs either : ■ simultaneously on both TIP and RING lines versus GND. ■ between TIP and RING. ■ on TIP (or RING) versus GND. CLP30-200B1 The choice of the switching-on current is function of the RSENSE resistors. Fig . 7a and 7b : Switching-on current versus RSENSE Iswon @ 25°C ( mA ) Iswon negative surge ( mA ) 1000 1000 Iswon + min Iswon + max Iswon - min Iswon - max Iswon - @ 0°C Iswon - @ +25°C Iswon - @ +70°C Rsense ( Ohms ) Rsense ( Ohms ) 100 100 1.6 3 6 1.6 3 6 This current (typically above 150 mA) should not activate the protection device CLP30-200B1. Therefore the level of activation is to be chosen just below this limit (typically 200mA). This level is adjusted through RSENSE. Figures 7a and 7b enable the designers to choose the right RSENSE value. Example: The choice of RSENSE = 3 Ω ensures a negative triggering of -280 mA min and -380mA max. In this case, the positive triggering will be 220mA min and 320mA max. Thanks to the CLP30-200B1 topology, the surge current in the line is reduced after it. Because the remaining surge energy is low, the power ratings of RP, the relay contacts and the external voltage reference device may be kept low. This results in a significant cost reduction for the whole system. 7/11 CLP30-200B1 ABSOLUTE MAXIMUM RATINGS (RSENSE = 3 Ω,Tamb = 25°C) Symbol IPP Parameter Value Unit 30 45 A 8.5 4.5 3.5 A -40 to +150 150 °C 260 °C Line to GND peak pulse current 10/1000 µs (open circuit voltage wave shape 10/1000 µs) 5/310 µs (open circuit voltage wave shape 10/700 µs) ITSM Non repetitive surge peak on-state current F = 50 Hz Tstg Tj Storage temperature range Maximum junction temperature TL Lead temperature for soldering during 10 s. tp = 10 ms tp = 200 ms tp = 1 s ELECTRICAL CHARACTERISTICS (RSENSE = 3 Ω, and Tamb = 25 °C) Symbol Parameter Test condtions Min ILGL Line to GND leakage current VLG Line to GND operating voltage VSWON Line to GND voltage at SW1 or SW2 switching-on Measured at 50 Hz between TIPL (or RINGL) and GND,one cycle ISWOFF Line to GND negative current at SW1 or SW2 switching-off Refer to test circuit fig 9 150 ISWON Line current at SW1 or SW2 switching-on Positive surge Negative surge 220 370 Line to GND capacitance VLG = 0V VOSC= 200mVRMS F = 1MHz C VLG = 200 V Measured between TIP (or RING) and GND Max Unit 10 µA 200 V 290 V mA 320 470 mA 100 pF THERMAL RESISTANCE Symbol Rth(j-a) 8/11 Parameter Junction to ambient Value Unit 170 °C/W CLP30-200B1 Fig.8 : TEST CIRCUIT FOR ISWOFF PARAMETER : GO - NO GO TEST TIPL or RINGL R -V D.U.T. BAT = - 48 V GND Surge generator This is a GO-NO GO test which allows to confirm the switch-off current (IH) level in functional test circuit. TEST PROCEDURE - Adjust the current level at the ISWOFF value by short circuiting the D.U.T - Fire the D.U.T with a surge current : IPP = 10 A, 10/1000 µs - The D.U.T will come back to the off-state within a duration of 50 ms max. Fig. 9 : Typical variation of switching-on current (positive or negative) versus RSENSE resistor and junction temperature (see test condition Fig. 11). Fig. 10 : Variation of switching-on current versus RSENSE at 25 °C. Iswon @ 25°C ( mA ) Iswon negative surge ( mA ) 1000 1000 Iswon + min Iswon + max Iswon - min Iswon - max Iswon - @ 0°C Iswon - @ +25°C Iswon - @ +70°C Rsense ( Ohms ) Rsense ( Ohms ) 100 100 1.6 3 6 Fig. 11 : ISWON MEASUREMENT - ISWON = l1 when the CLP30-200B1 switches on (l1 is progressively increased using R) - Both TIP and RING sides of the CLP30-200B1 are checked - RL = 10Ω . Rsense RL 1.6 3 6 fig. 12 : Relative variation of switching-off current versus junction temperature (for RSENSE between 3 and 10 Ω). ISWOFF [Tj°C] / ISWOFF [25°C] 1.4 1.2 I1 1 ± 48 V TIPL 0.8 TIPS R DUT 0.6 GND RINGL RINGS 0.4 0 20 40 Temperature (°C) 60 80 9/11 CLP30-200B1 Fig. 13 : Relative variation of switching-off current versus RSENSE (between 3 and 10 Ω). Fig. 14 : Relative variation of switching-on voltage versus dV/dt with an external resistor of 3 Ω. ISWOFF [Rsense] / ISWOFF [4 Ω] VSWON / VREF 1.6 1.12 1.4 1.10 1.08 1.2 1.06 1.0 1.04 0.8 1.02 0.6 0.4 4 6 8 Rsense ( Ω ) 1.00 0.98 0.1 10 0.3 1 3 10 30 100 300 1000 dV/dt (V/µs) Fig. 15 : Relative variation of internal reference voltage versus junction temperature (ILG =1mA). Fig. 16 : Capacitance (TIP/GND) versus applied voltage (typical values). C (pF) 70 VREF [Tj°C] / V REF [25°C] 1.10 50 1.05 30 1.00 0.95 20 0.90 0.85 -40 -20 0 20 40 60 10 Tj (°C) Fig. 17 : Surge peak current versus overload duration (maximum values). 10 ITSM(A) 8 6 4 2 t(s) 0 0.01 10/11 0.1 1 10 100 1000 1 2 3 5 10 VR (V) 20 30 50 100 CLP30-200B1 PACKAGE MECANICAL DATA SO8 plastic DIMENSIONS REF. Millimetres Min. c1 a1 C a3 a2 A e b b1 a1 S E e3 D M F 1 0.1 a2 Typ. Max. 1.75 0.069 0.25 0.004 0.010 1.65 0.065 a3 0.65 0.85 0.025 0.033 b 0.35 0.48 0.014 0.019 b1 0.19 0.25 0.007 0.010 C 0.25 0.50 0.010 0.020 0.50 c1 5 8 Typ. Max. Min. A L Inches 45° (typ) D 4.8 5.0 0.189 0.197 E 5.8 6.2 0.228 0.244 4 e 1.27 0.050 e3 3.81 0.150 F 3.8 4.0 0.15 0.157 L 0.4 1.27 0.016 0.050 0.6 0.024 M S 8° (max) MARKING Ordering code Marking Package Weight Base qty Delivery mode CLP30-200B1 CLP30 SO-8 0.08g 100 Tube CLP30-200B1RL CLP30 SO-8 0.08g 2500 Tape & Reel 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 infringement of 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. The ST logo is a registered trademark of STMicroelectronics © 1999 STMicroelectronics - Printed in Italy - All rights reserved. STMicroelectronics GROUP OF COMPANIES Australia - Brazil - China - Finland - France - Germany - Hong Kong - India - Italy - Japan - Malaysia Malta - Morocco - Singapore - Spain - Sweden - Switzerland - United Kingdom - U.S.A. http://www.st.com 11/11