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TISP61511D, TISP61512P DUAL FORWARD-CONDUCTING P-GATE THYRISTORS PROGRAMMABLE OVERVOLTAGE PROTECTORS
Copyright (c) 1997, Power Innovations Limited, UK JULY 1995 - REVISED SEPTEMBER 1997
PROGRAMMABLE SLIC OVERVOLTAGE PROTECTION
q
Dual Voltage-Programmable Protectors. - Wide 0 to -80 V Programming Range - Low 5 mA max. Triggering Current - High 150 mA min. Holding Current Rated for International Surge Wave Shapes
VOLTAGE WAVE SHAPE 2/10 s 1.2/50 s 0.5/700 s 10/700 s 10/1000 s STANDARD TR-NWT-001089 ETS 300 047-1 RLM88/I3124 K17, K20, K21 TR-NWT-001089 ITSP A 170 90 40 40 30
'61511D PACKAGE (TOP VIEW)
(Tip)
K1 NC
1 2 3 4
8 7 6 5
K1 (Tip) A A (Ground) (Ground)
(Gate) G (Ring) K2
q
K2 (Ring)
MD6XAL
NC - No internal connection Terminal typical application names shown in parenthesis '61512P PACKAGE (TOP VIEW)
(Tip)
K1
1 2 3 4
8 7 6 5
K1 (Tip) A A (Ground) (Ground)
q
Functional Replacements for
DEVICE TYPE LCP1511, LCP1511D, ATTL7591AS, MGSS150-1 LCP1512, LCP1512D, ATTL7591AB, MGSS150-2 8-pin Plastic DIP TISP61512P 8-pin Small-Outline PACKAGE TYPE FUNCTIONAL REPLACEMENT TISP61511D or order as TISP61511DR for Taped and Reeled
(Gate) G NC (Ring) K2
K2 (Ring)
MD6XAJ
NC - No internal connection Terminal typical application names shown in parenthesis
device symbol
K1 G K2
description
The TISP61511D and TISP61512P are dual forward-conducting buffered p-gate overvoltage protectors. They are designed to protect monolithic Subscriber Line Interface Circuits, SLICs, against overvoltages on the telephone line caused by lightning, ac power contact and induction. The TISP61511D and TISP61512P limit voltages that exceed the SLIC supply rail voltage.
A
SD6XAE
Terminals K1, K2 and A correspond to the alternative line designators of T, R and G or A, B and C. The negative protection voltage is controlled by the voltage, VGG, applied to the G terminal.
The SLIC line driver section is typically powered from 0 V (ground) and a negative voltage in the region of -10 V to -70 V. The protector gate is connected to this negative supply. This references the protection (clipping) voltage to the negative supply voltage. As the protection voltage will track the negative supply voltage the overvoltage stress on the SLIC is minimised. Positive overvoltages are clipped to ground by diode forward conduction. Negative overvoltages are initially clipped close to the SLIC negative supply rail value. If sufficient current is available from the overvoltage, then the protector will crowbar into a low voltage on-state condition. As the current subsides the high holding current of the crowbar prevents d.c. latchup. These monolithic protection devices are fabricated in ion-implanted planar vertical power structures for high reliability and in normal system operation they are virtually transparent. The buffered gate design reduces the loading on the SLIC supply during overvoltages caused by power cross and induction.
PRODUCT
INFORMATION
Information is current as of publication date. Products conform to specifications in accordance with the terms of Power Innovations standard warranty. Production processing does not necessarily include testing of all parameters.
1
TISP61511D, TISP61512P DUAL FORWARD-CONDUCTING P-GATE THYRISTORS PROGRAMMABLE OVERVOLTAGE PROTECTORS
JULY 1995 - REVISED SEPTEMBER 1997
absolute maximum ratings
RATING Repetitive peak off-state voltage, IG = 0, -40C TJ 85C Repetitive peak gate-cathode voltage, V KA = 0, -40C TJ 85C Non-repetitive peak on-state pulse current (see Notes 1 and 2) 10/1000 s 5/310 s 0.2/310 s 1/20 s 2/10 s Non-repetitive peak on-state current, 50 Hz (see Notes 1 and 2) full-sine-wave, 20 ms 1s Non-repetitive peak gate current, half-sine-wave, 10 ms (see Notes 1 and 2) Junction temperature Storage temperature range IGSM TJ Tstg ITSM 5 3.5 2 -55 to +150 -55 to +150 A C C A TJ = -40C TJ = 25, 85C ITSP 30 40 40 90 120 170 A SYMBOL VDRM VGKRM VALUE -100 -85 UNIT V V
NOTES: 1. Initially the protector must be in thermal equilibrium with -40C TJ 85C, unless otherwise specified. The surge may be repeated after the device returns to its initial conditions. See the applications section for the details of the impulse generators. 2. The rated current values may be applied to either the R-G or T-G terminal pairs. Additionally, both terminal pairs may have their rated current values applied simultaneously (in this case the G terminal current will be twice the rated current value of an individual terminal pair). Above 85C, derate linearly to zero at 150C lead temperature.
recommended operating conditions
MIN CG Gate decoupling capacitor TYP 220 MAX UNIT nF
electrical characteristics, TJ = 25C (unless otherwise noted)
PARAMETER ID V(BO) VGK(BO) Off-state current Breakover voltage Gate-cathode voltage at breakover On-state voltage Forward voltage Peak forward recovery voltage Holding current Gate reverse current Gate trigger current Gate trigger voltage VD = -85 V, VGK = 0 V TEST CONDITIONS TJ = 25C TJ = 70C MIN TYP MAX 5 50 -58 10 20 25 3 4 3 5 5 7 12 150 TJ = 25C TJ = 70C 0.2 5 50 5 2.5 mA A A mA V V V V V UNIT A A V
IT = 30 A, 10/1000 s, 1 kV, RS = 33 , di/dt(i) = 8 A/s (see Note 3) IT = 30 A, 10/700 s, 1.5 kV, RS= 10 , di/dt(i) = 14 A/s (see Note 3) IT = 30 A, 1.2/50 s, 1.5 kV, RS= 10 , di/dt(i) = 70 A/s (see Note 3) IT = 38 A, 2/10 s, 2.5 kV, RS= 61 , di/dt(i) = 40 A/s (see Note 3) IT = 0.5 A, tw = 500 s IT = 3 A, tw = 500 s IF = 5 A, tw = 500 s IF = 30 A, 10/1000 s, 1 kV, RS = 33 , di/dt(i) = 8 A/s (see Note 3) IT = 30 A, 10/700 s, 1.5 kV, RS= 10 , di/dt(i) = 14 A/s (see Note 3) IT = 30 A, 1.2/50 s, 1.5 kV, RS= 10 , di/dt(i) = 70 A/s (see Note 3) IT = 38 A, 2/10 s, 2.5 kV, RS= 61 , di/dt(i) = 40 A/s (see Note 3) IT = 1 A, di/dt = -1A/ms, VGG = -48 V VGG = -75 V, K and A terminals connected IT = 3 A, tp(g) 20 s, VGG = -48 V IT = 3 A, tp(g) 20 s, VGG = -48 V
VT VF
VFRM
IH IGAS IGT VGT NOTE
3: All tests have CG = 220 nF and VGG = -48 V. RS is the current limiting resistor between the output of the impulse generator and the R or T terminal. See the applications section for the details of the impulse generators.
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INFORMATION
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TISP61511D, TISP61512P DUAL FORWARD-CONDUCTING P-GATE THYRISTORS PROGRAMMABLE OVERVOLTAGE PROTECTORS
JULY 1995 - REVISED SEPTEMBER 1997
electrical characteristics, TJ = 25C (unless otherwise noted) (Continued)
PARAMETER CAK Anode-cathode offstate capacitance TEST CONDITIONS f = 1 MHz, Vd = 1 V, IG = 0, (see Note 4) VD = -3 V V D = -48 V MIN TYP MAX 100 50 UNIT pF pF
NOTE
4: These capacitance measurements employ a three terminal capacitance bridge incorporating a guard circuit. The unmeasured device terminals are a.c. connected to the guard terminal of the bridge.
thermal characteristics
PARAMETER RJA Junction to free air thermal resistance TEST CONDITIONS Ptot = 0.8 W, TA = 25C 5 cm2, FR4 PCB D Package P Package MIN TYP MAX 170 125 UNIT C/W
PARAMETER MEASUREMENT INFORMATION
+i IFSP (= |ITSP|) Quadrant I Forward Conduction Characteristic
IFSM (= |ITSM|) IF VF VGK(BO) VGG VD ID
-v
+v
I(BO) IS
IH VT IT ITSM
V(BO)
VS
Quadrant III Switching Characteristic ITSP -i
PM6XAAA
Figure 1. VOLTAGE-CURRENT CHARACTERISTIC
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TISP61511D, TISP61512P DUAL FORWARD-CONDUCTING P-GATE THYRISTORS PROGRAMMABLE OVERVOLTAGE PROTECTORS
JULY 1995 - REVISED SEPTEMBER 1997
THERMAL INFORMATION
MAXIMUM NON-RECURRING 50 Hz CURRENT vs CURRENT DURATION
TI6LAA
ITRMS - Maximum Non-Recurrent 50 Hz Current - A
VGEN = 250 Vrms RGEN = 10 to 150 10
TISP61512P
TISP61511D 1 0*1 1 10 100 1000
t - Current Duration - s
Figure 2.
DEVICE PARAMETERS
general
Thyristor based overvoltage protectors, for telecommunications equipment, became popular in the late 1970s. These were fixed voltage breakover triggered devices, likened to solid state gas discharge tubes. As these were new forms of thyristor, the existing thyristor terminology did not cover their special characteristics. This resulted in the invention of new terms based on the application usage and device characteristic. Initially, there was a wide diversity of terms to describe the same thing, but today the number of terms have reduced and stabilised. Programmable, (gated), overvoltage protectors are relatively new and require additional parameters to specify their operation. Similarly to the fixed voltage protectors, the introduction of these devices has resulted in a wide diversity of terms to describe the same thing. To help promote an understanding of the terms and their alternatives, this section has a list of alternative terms and the parameter definitions used for this data sheet. In general, the Texas Instruments approach is to use terms related to the device internal structure, rather than its application usage as a single device may have many applications each using a different terminology for circuit connection.
alternative symbol cross-reference guide
This guide is intended to help the translation of alternative symbols to those used in this data sheet. As in some cases the alternative symbols have no substance in international standards and are not fully defined by the originators, users must confirm symbol equivalence. No liability will be assumed from the use of this guide.
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TISP61511D, TISP61512P DUAL FORWARD-CONDUCTING P-GATE THYRISTORS PROGRAMMABLE OVERVOLTAGE PROTECTORS
JULY 1995 - REVISED SEPTEMBER 1997 DATA SHEET ALTERNATIVE SYMBOL ITSP ID IR IRM IRG VR VRM VFP VSGL Vgate VG VDRM VGKM VGK VGK(BO) VK CAK K1 K2 A G RJA VGATE VS VMLG VMGL VGL VDGL VLG VGND/LINE Coff Tip Ring GND Gate Rth (j-a) Maximum voltage LINE/GND Maximum voltage GATE/LINE GATE/LINE voltage Dynamic switching voltage GATE/LINE LINE/GND voltage Off-state capacitance LINE/GND Tip terminal Ring terminal Ground terminal Gate terminal Thermal Resistance, junction to ambient GATE/GND voltage SYMBOL IPP TISP61511D, TISP61512P PARAMETER Non-repetitive peak on-state pulse current Off-state current ALTERNATIVE PARAMETER Peak pulse current Reverse leakage current LINE/GND Reverse leakage current GATE/LINE Reverse voltage LINE/GND Peak forward voltage LINE/GND Dynamic switching voltage GND/LINE
Gate reverse current (with A and K terminals connected) IGAS Off-state voltage Peak forward recovery voltage Breakover voltage Gate voltage, (VGG is gate supply voltage referenced to the A terminal) Repetitive peak off-state voltage Repetitive peak gate-cathode voltage Gate-cathode voltage Gate-cathode voltage at breakover Cathode-anode voltage Anode-cathode capacitance Cathode 1 terminal Cathode 2 terminal Anode terminal Gate terminal Thermal Resistance, junction to ambient VD VFRM V(BO)
APPLICATIONS INFORMATION
electrical characteristics
The electrical characteristics of a thyristor overvoltage protector are strongly dependent on junction temperature, TJ. Hence a characteristic value will depend on the junction temperature at the instant of measurement. The values given in this data sheet were measured on commercial testers, which generally minimise the temperature rise caused by testing.
application circuit
Figure 3 shows a typical TISP6151xx SLIC card protection circuit. The incoming line wires, R and T, connect to the relay matrix via the series over-current protection. Fusible resistors, fuses and positive temperature coefficient (PTC) resistors can be used for over-current protection. Resistors will reduce the prospective current from the surge generator for both the TISP6151xx and the ring/test protector. The TISP7xxxF3 protector has the same protection voltage for any terminal pair. This protector is used when the ring generator configuration maybe ground or battery-backed. For dedicated ground-backed ringing generators, the TISP3xxxF3 gives better protection as its inter-wire protection voltage is twice the wire to ground value. Relay contacts 3a and 3b connect the line wires to the SLIC via the TISP6151xx protector. The protector gate reference voltage comes from the SLIC negative supply (VBAT). A 220 nF gate capacitor sources the high gate current pulses caused by fast rising impulses.
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INFORMATION
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TISP61511D, TISP61512P DUAL FORWARD-CONDUCTING P-GATE THYRISTORS PROGRAMMABLE OVERVOLTAGE PROTECTORS
JULY 1995 - REVISED SEPTEMBER 1997 OVERCURRENT PROTECTION TIP WIRE R1a
RING/TEST PROTECTION Th1
TEST RELAY
RING RELAY
SLIC RELAY S3a
SLIC PROTECTOR Th4
SLIC
S1a Th3
S2a
RING WIRE
R1b
Th2 TISP 3xxxF3 OR 7xxxF3 S3b S1b S2b
Th5 TISP 6151xx VBAT 220 nF
TEST EQUIPMENT
RING GENERATOR
AI6XAA
Figure 3. TYPICAL APPLICATION CIRCUIT
impulse conditions
Most lightning tests, used for equipment verification, specify a unidirectional sawtooth waveform which has an exponential rise and an exponential decay. Wave shapes are classified in terms of Peak Amplitude (voltage or current), rise time and a decay time to 50% of the maximum amplitude. The notation used for the wave shape is amplitude, rise time/decay time. A 38 A, 5/310 s wave shape would have a peak current value of 38 A, a rise time of 5 s and a decay time of 310 s. There are three categories of surge generator type, single wave shape, combination wave shape and circuit defined. Single wave shape generators have essentially the same waveshape for the open circuit voltage and short circuit current (e.g. 10/1000 s open circuit voltage and short circuit current). Combination generators have two wave shapes, one for the open circuit voltage and the other for the short circuit current (e.g. 1.2/50 s open circuit voltage and 8/20 s short circuit current). Circuit specified generators usually equate to a combination generator, although typically only the open circuit voltage waveshape is referenced (e.g. a 10/700 s open circuit voltage generator typically produces a 5/310 s short circuit current). If the combination or circuit defined generators operate into a finite resistance the wave shape produced is intermediate between the open circuit and short circuit values. When the TISP switches into the on-state it has a very low impedance. As a result, although the surge wave shape may be defined in terms of open circuit voltage, it is the current waveshape that must be used to assess the TISP surge requirement. As an example, the CCITT IX K17 1.5 kV, 10/700 s surge is changed to a 38 A 5/310 s waveshape when driving into a short circuit. The impulse generators used for rated values are tabulated below
IMPULSE GENERATORS USED FOR RATED VALUES PEAK STANDARD VOLTAGE SETTING V TR-NWT-001089 2500 VOLTAGE WAVE FORM s 2/10 GENERATOR FICTIVE SOURCE IMPEDANCE 5 EXTERNAL SERIES RESISTANCE 10 A 170 PEAK CURRENT CURRENT WAVE FORM s 2/10
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INFORMATION
6
TISP61511D, TISP61512P DUAL FORWARD-CONDUCTING P-GATE THYRISTORS PROGRAMMABLE OVERVOLTAGE PROTECTORS
JULY 1995 - REVISED SEPTEMBER 1997 IMPULSE GENERATORS USED FOR RATED VALUES PEAK STANDARD VOLTAGE SETTING V ETS 300 047-1 RLM88/I3124 K17, K20, K21 TR-NWT-001089 3000 1600 1600 1000 VOLTAGE WAVE FORM s 1.2/50 0.5/700 10/700 10/1000 GENERATOR FICTIVE SOURCE IMPEDANCE 38 40 40 10 EXTERNAL SERIES RESISTANCE 0 0 0 23 A 80 40 40 30 PEAK CURRENT CURRENT WAVE FORM s 0.6/18 0.2/310 5/310 10/1000
Figures 4. and 5. show how the TISP6151xx limits negative and positive over-voltages. Negative overvoltages (Figure 4.) are initially clipped close to the SLIC negative supply rail value (VBAT). If sufficient current is available from the overvoltage, then the protector (Th5) will crowbar into a low voltage on-state condition. As the overvoltage subsides the high holding current of the crowbar prevents dc latchup. The protection voltage will be the sum of the gate supply (VBAT) and the peak gate-cathode voltage (VGK(BO)). The protection voltage will be increased if there is a long connection between the gate decoupling capacitor, C, and the gate terminal. During the initial rise of a fast impulse, the gate current (IG) is the same as the cathode current (IK). Rates of 70 A/s can cause inductive voltages of 0.7 V in 2.5 cm of printed wiring track. To minimise this inductive voltage increase of protection voltage, the length of the capacitor to gate terminal tracking should be minimised. Inductive voltages in the protector cathode wiring can increase the protection voltage. These voltages can be minimised by routing the SLIC connection through the protector as shown in Figure 3.
SLIC PROTECTOR SLIC PROTECTOR
SLIC
SLIC
IK
Th5 TISP 6151xx C 220 nF IG VBAT AI6XAB
IF
Th5 TISP 6151xx VBAT 220 nF AI6XAC
Figure 4. NEGATIVE OVERVOLTAGE CONDITION
Figure 5. POSITIVE OVERVOLTAGE CONDITION
Positive overvoltages (Figure 5.) are clipped to ground by forward conduction of the diode section in protector (Th5). Fast rising impulses will cause short term overshoots in forward voltage (VFRM). The thyristor protection voltage, (V(BO)) increases under lightning surge conditions due to thyristor regeneration time. This increase is dependent on the rate of current rise, di/dt, when the TISP is clamping the voltage in its breakdown region. The diode protection voltage, known as the forward recovery voltage, (VFRM ) is dependent on the rate of current rise, di/dt. An estimate of the circuit di/dt can be made from the surge
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INFORMATION
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TISP61511D, TISP61512P DUAL FORWARD-CONDUCTING P-GATE THYRISTORS PROGRAMMABLE OVERVOLTAGE PROTECTORS
JULY 1995 - REVISED SEPTEMBER 1997
generator voltage rate of rise, dv/dt, and the circuit resistance. The impulse generators used for characterising the protection voltages are tabulated below
IMPULSE GENERATORS USED FOR ELECTRICAL CHARACTERISTIC VALUES PEAK STANDARD VOLTAGE SETTING V TR-NWT-001089 ETS 300 047-1 K17, K20, K21 TR-NWT-001089 2500 1500 1500 1000 VOLTAGE WAVE FORM s 2/10 1.2/50 10/700 10/1000 GENERATOR FICTIVE SOURCE IMPEDANCE 5 38 40 10 EXTERNAL SERIES RESISTANCE 61 12 10 23 A 38 30 30 30 PEAK CURRENT di/dt(i) INITIAL RATE OF RISE A/s 40 70 14 8 CURRENT WAVE FORM s 2/10 0.6/21 5/350 10/1000
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INFORMATION
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TISP61511D, TISP61512P DUAL FORWARD-CONDUCTING P-GATE THYRISTORS PROGRAMMABLE OVERVOLTAGE PROTECTORS
JULY 1995 - REVISED SEPTEMBER 1997
MECHANICAL DATA
D008 plastic small-outline package
This small-outline package consists of a circuit mounted on a lead frame and encapsulated within a plastic compound. The compound will withstand soldering temperature with no deformation, and circuit performance characteristics will remain stable when operated in high humidity conditions. Leads require no additional cleaning or processing when used in soldered assembly.
D008 5,00 (0.197) 4,80 (0.189) 8 7 6 5 Designation per JEDEC Std 30: PDSO-G8
6,20 (0.244) 5,80 (0.228)
4,00 (0.157) 3,81 (0.150)
1
2
3
4
1,75 (0.069) 1,35 (0.053)
7 NOM 3 Places
0,50 (0.020) x 45NOM 0,25 (0.010)
5,21 (0.205) 4,60 (0.181)
0,203 (0.008) 0,102 (0.004) 0,79 (0.031) 0,28 (0.011) Pin Spacing 1,27 (0.050) (see Note A) 6 Places
0,51 (0.020) 0,36 (0.014) 8 Places 0,229 (0.0090) 0,190 (0.0075)
7 NOM 4 Places
4 4
1,12 (0.044) 0,51 (0.020)
ALL LINEAR DIMENSIONS ARE IN MILLIMETERS AND PARENTHETICALLY IN INCHES
MDXXAA
NOTES: A. B. C. D.
Leads are within 0,25 (0.010) radius of true position at maximum material condition. Body dimensions do not include mold flash or protrusion. Mold flash or protrusion shall not exceed 0,15 (0.006). Lead tips to be planar within 0,051 (0.002).
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INFORMATION
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TISP61511D, TISP61512P DUAL FORWARD-CONDUCTING P-GATE THYRISTORS PROGRAMMABLE OVERVOLTAGE PROTECTORS
JULY 1995 - REVISED SEPTEMBER 1997
MECHANICAL DATA
P008 plastic dual-in-line package
This dual-in-line package consists of a circuit mounted on a lead frame and encapsulated within a plastic compound. The compound will withstand soldering temperature with no deformation, and circuit performance characteristics will remain stable when operated in high humidity conditions The package is intended for insertion in mounting-hole rows on 7,62 (0.300) centers. Once the leads are compressed and inserted, sufficient tension is provided to secure the package in the board during soldering. Leads require no additional cleaning or processing when used in soldered assembly.
P008 10,2 (0.400) MAX 8 7 6 5 Designation per JEDEC Std 30: PDIP-T8
Index Dot C L 7,87 (0.310) 7,37 (0.290) T.P. 6,60 (0.260) 6,10 (0.240) C L
1
2
3
4
1,78 (0.070) MAX 4 Places
5,08 (0.200) MAX Seating Plane 0,51 (0.020) MIN 105 90 8 Places
3,17 (0.125) MIN 2,54 (0.100) T.P. 6 Places (see Note A) 0,533 (0.021) 0,381 (0.015) 8 Places
0,36 (0.014) 0,20 (0.008) 8 Places
ALL LINEAR DIMENSIONS ARE IN MILLIMETERS AND PARENTHETICALLY IN INCHES NOTE A: Each pin centerline is located within 0,25 (0.010) of its true longitudinal position
MDXXABA
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TISP61511D, TISP61512P DUAL FORWARD-CONDUCTING P-GATE THYRISTORS PROGRAMMABLE OVERVOLTAGE PROTECTORS
JULY 1995 - REVISED SEPTEMBER 1997
IMPORTANT NOTICE
Power Innovations Limited (PI) reserves the right to make changes to its products or to discontinue any semiconductor product or service without notice, and advises its customers to verify, before placing orders, that the information being relied on is current. PI warrants performance of its semiconductor products to the specifications applicable at the time of sale in accordance with PI's standard warranty. Testing and other quality control techniques are utilized to the extent PI deems necessary to support this warranty. Specific testing of all parameters of each device is not necessarily performed, except as mandated by government requirements. PI accepts no liability for applications assistance, customer product design, software performance, or infringement of patents or services described herein. Nor is any license, either express or implied, granted under any patent right, copyright, design right, or other intellectual property right of PI covering or relating to any combination, machine, or process in which such semiconductor products or services might be or are used. PI SEMICONDUCTOR PRODUCTS ARE NOT DESIGNED, INTENDED, AUTHORIZED, OR WARRANTED TO BE SUITABLE FOR USE IN LIFE-SUPPORT APPLICATIONS, DEVICES OR SYSTEMS.
Copyright (c) 1997, Power Innovations Limited
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