Features
This series is currently available but
not recommended for new designs.
n Low capacitance
n Low distortion
U1
n Surge protection
80
n RoHS compliant*
1L
TISP4G024L1W G.Fast VDSL Protector
General Information
This device is designed to protect ADSL, VDSL and G.Fast line driver interfaces from
overvoltages up to rated limits. Overvoltages are normally caused by a.c. power-system
or lightning-flash disturbances which are induced or conducted onto the telephone line.
This protector offers protection of both lines of the twisted wire pair in a single device.
When placed between the xDSL line driver IC and the transformer, this protector will
clamp and switch into a low-impedance state, safely diverting the current transferred by
the xDSL coupling transformer. The biased low capacitance design makes this device
suitable for designs from ADSL to 30MHz VDSL2 to G.Fast.
I/O 1
REF
GND
REF
Telecom ports need protection against longitudinal and transverse surges, to comply
I/O 2
REF
with international standards such as ITU-T K.20, K.21 or K.45, Telcordia GR-1089-CORE
and YD/T. Longitudinal surges are resisted by the galvanic isolation of the coupling
transformer which is commonly rated to 2 kV or greater. Transverse surges can be
transmitted by the transformer, and can stress the Line Driver Interface IC. As the xDSL interface circuit is designed to operate from
3 kHz to 106 MHz, nearby high frequency events – such as cable flashover or primary protection activation – can generate damaging
conditions for the interface requiring this type of protection.
Absolute Maximum Ratings, TA = 25 °C (Unless Otherwise Noted)
Rating
Repetitive Peak Off-State Voltage
Non-repetitive Peak Impulse Current, 8/20 µs
ESD (IEC 61000-4-2 Contact)
ESD (IEC 61000-4-2 Air)
Junction Temperature
Storage Temperature
Symbol
VDRM
IPPSM
Rating
24
Unit
V
A
kV
kV
°C
°C
30
8
15
-40 to +150
-55 to +150
TJ
TSTG
Electrical Characteristics, TA = 25 °C (Unless Otherwise Noted)
Parameter
ID
Test Condition (Note 1)
Leakage Current
Min.
VD = VDRM
V(BO) Breakover Voltage
di/dt = ±1 mA/µs
Typ.
30
Max.
Unit
100
nA
34
V
I(BO) Breakover Current
VT
On-state Voltage
di/dt = ±1 mA/µs
80
mA
IT = ±1 A
3.8
V
1
V
IH
C
40
mA
Capacitance
IT = ±5 A di/dt = 1 mA/µs
DC
Capacitance Variation
VT
On-state Voltage
IT = 1 A, REF to GND
Holding Current
VD = 2 V, f = 10 MHz, Vd =1 Vrms
VD = 1 V to VDRM, f = 10 MHz, Vd =1 Vrms
0.4
0.02
3
pF
pF
Note 1: All measurements made between I/O 1 and I/O 2 unless otherwise stated.
Agency Recognition
Description
UL
File Number: E215609
OCTOBER 2015 – REVISED JULY 2019
WARNING Cancer and Reproductive Harm
www.P65Warnings.ca.gov
*RoHS Directive 2015/863, Mar 31, 2015 and Annex. Specifications are subject to change without notice.
Users should verify actual device performance in their specific applications.
The products described herein and this document are subject to specific legal disclaimers as set forth on the last
page of this document, and at www.bourns.com/docs/legal/disclaimer.pdf.
Applications
n G.Fast equipment
n xDSL modems and line cards
TISP4G024L1W G.Fast VDSL Protector
Parameter Measurement Information
OCTOBER 2015 – REVISED JULY 2019
Specifications are subject to change without notice.
Users should verify actual device performance in their specific applications.
The products described herein and this document are subject to specific legal disclaimers as set forth on the last page of this document, and at www.bourns.com/docs/legal/disclaimer.pdf.
TISP4G024L1W
G.Fast
VDSL Protector
3312
- 2 mm SMD
Trimming
Potentiometer
Typical Characteristics
8/20 µs Pulse Waveform
Leakage Current vs Junction Temperature
100000
120
80
et
60
40
VD = 24 V
10000
ID - Leakage Current (nA)
tr
100
IPP – Peak Pulse Current (% of IPP)
Test Waveform Parameters
tr = 8 µs
td = 20 µs
td = t|IPP/2
1000
20
100
10
1
0
0
5
10
15
20
25
-40
30
-10
t – Time (µs)
Breakover Voltage vs Junction Temperature
50
di/dt = 1 mA/µs
70
IH - Holding Current (mA)
V(BO) - Breakover Voltage (V)
31
30
29
28
27
26
140
IT = 5 A
di/dt = 1 mA/µs
60
50
40
30
20
10
25
-10
20
50
80
110
0
-40
140
TJ - Junction Temperature (°C)
20
50
80
110
140
3.0
30
2.5
C - Capacitance (pF)
25
OCTOBER 2015 – REVISED JULY 2019
-10
TJ - Junction Temperature (°C)
35
VT - On-State Voltage (V)
110
80
32
24
-40
80
Holding Current vs Junction Temperature
34
33
20
TJ - Junction Temperature (°C)
2.0
f = 10 MHz
Vd = 1 VRMS
TJ = 25 °C
Specifications are subject to change without notice.
20
Users should verify actual device performance in their specific applications.
1.5
The products described herein and this document are subject to specific legal disclaimers as set forth on the last page of this document, and at www.bourns.com/docs/legal/disclaimer.pdf.
15
10
1.0
34
80
33
di/dt = 1 mA/µs
70
IT = 5 A
di/dt = 1 mA/µs
IH - Holding Current (mA)
V(BO) - Breakover Voltage (V)
32
31
30
29
28
27
26
60
50
40
30
20
10
25
TISP4G024L1W
G.Fast VDSL Protector
24 3312 - 2 mm SMD Trimming Potentiometer0
-40
-10
20
50
80
110
140
-40
-10
TJ - Junction Temperature (°C)
Typical Characteristics (Continued)
On-State Voltage vs On-State Current
50
80
110
140
Capacitance vs Off-State Voltage
35
3.0
30
f = 10 MHz
Vd = 1 VRMS
TJ = 25 °C
2.5
25
C - Capacitance (pF)
VT - On-State Voltage (V)
20
TJ - Junction Temperature (°C)
20
15
10
2.0
1.5
1.0
0.5
5
0
0
0
10
20
30
IT - On-State Current (A)
OCTOBER 2015 – REVISED JULY 2019
40
50
0
2
4
6
8
10 12
14
16 18
20
22 24
VD - Off-State Voltage (V)
Specifications are subject to change without notice.
Users should verify actual device performance in their specific applications.
The products described herein and this document are subject to specific legal disclaimers as set forth on the last page of this document, and at www.bourns.com/docs/legal/disclaimer.pdf.
TISP4G024L1W G.Fast VDSL Protector
Application Information
The Bourns® Model TISP4G024L1W is designed to protect xDSL and G.Fast line driver interfaces from overvoltage conditions up to
rated limits. However, it can be used in other applications as well. The typical breakover voltage and current are specified as 30 V and
80 mA, respectively. It has a repetitive peak off-state voltage rating of 24 V and a peak current rating of 30 A for an 8/20 μs current
waveform.
Figure 1 shows a typical G.Fast application circuit which uses the TISP4G024L1W device for protection on the line driver side of the
signal transformer. Two series resistors (typically 50 ohms each when a 1:1 transformer is used) which terminate the differential signal
pair may be placed between the line driver outputs and the connections to the protection device and transformer. These resistors will
also limit the current that the line driver is subjected to during a surge event. The signal lines are ac coupled between the transformer
and the I/O (Input/output) connector.
V+
1:1
RS
1
8
2
7
1
VV-
V+
RB1
2
5
3
RS
RB2
To Connector
V+
TISP4G024L1W
3
6
4
5
Transformer
V-
Line Driver
Figure 1. G.Fast Application Circuit
Surge Protection in a G.Fast Application
In xDSL and G.Fast applications, the port is typically required to remain operational after being subjected to 10/700 μs transverse
surges up to 4 kV and longitudinal surges up to 6 kV when primary protection is used (ITU-T K.20, K.21 and K.44).
Transverse Surge Test
The surge performance of Figure 1 is characterized using a modified circuit shown in Figure 2, where the line driver and series
resistors were replaced with a single 100 ohm load resistor. Two 56 nF ac coupling caps are used to give an input capacitance of
28 nF, within the typical range of 27 to 33 nF that is used in xDSL and G.Fast applications. A Bourns® Model 2026-42-C2LF gas
discharge tube (GDT) is used as the primary protector for this evaluation.
1:1
C1
56 nF
1
8
2
7
3
6
4
5
25 Ω
1
RL
100 Ω
3
TISP4G024L1W
Transformer
C2
56 nF
15 Ω
2026-42-C2LF
10/700 µs Surge Generator
Figure 2. Transverse Surge Test Circuit in a G.Fast Application
OCTOBER 2015 – REVISED JULY 2019
Specifications are subject to change without notice.
Users should verify actual device performance in their specific applications.
The products described herein and this document are subject to specific legal disclaimers as set forth on the last page of this document, and at www.bourns.com/docs/legal/disclaimer.pdf.
TISP4G024L1W G.Fast VDSL Protector
Application Information (Continued)
Transverse Surge Test (Continued)
Figure 3 shows the response of the design to a 4 kV transverse surge. The ac coupling capacitors (C1 and C2) are being charged by
the surge current prior to the GDT firing. When the GDT fires (at 980 V), the voltage on the input lines is rapidly reduced to a low level,
resulting in a damped oscillation across the input side of the transformer, which is coupled directly to the load side. The peak current
on the load side of the transformer reaches 150 A during the first half cycle. The TISP4G024L1W device clamps to ~90 V at this
current. The damped oscillation in this case lasts ~3 cycles, quickly decaying within 2 μs. No components in the circuit were damaged
during the test.
Load Voltage
-90 V
GDT
FIRES
Load Side Current
980 V
GDT
Voltage
Surge Current
-150 A
100 A
Figure 3. 4 kV 10/700 μs Transverse Surge Response
Longitudinal Surge Response
Figure 4 shows the same application circuit as Figure 3, but with the test generator now configured to perform longitudinal surge tests.
Figure 5 shows the response of the design to a 6 kV 10/700 μs longitudinal surge. Voltage on both lines reaches 980 V before the one
side of the GDT fires, on Line 1 in this case, providing a path to ground for both lines. Subsequently, surge current will also flow from
Line 2 through the input capacitors into ground via Line 1. When the input capacitors charge the Line 2 voltage to 820 V, the other
side of the GDT fires. At this point, the response will be similar to that of the transverse surge, however, the surge current and voltage
are lower since the GDT fired at a lower voltage.
While the capacitors are charging, the peak current on the load side of the transformer reaches 28 A and the TISP4G024L1W device
clamps the voltage across the load below 20 V. After the second half of the GDT fires the damped oscillation begins, lasting about 3
cycles. The peak current on the load side is approximately 115 A with the TISP4G024L1W device clamping to 60 V. No components in
the circuit were damaged during the test.
This longitudinal surge response demonstrates one of three possible scenarios when a three terminal GDT is used as the primary
protector. The other two possibilities are: 1) Both sides of the GDT fire at the same or very close to the same time; and 2) the Line 2
side of the GDT fires before the Line 1 side. If both sides fire at the same time there will be a minimal amount of transverse current
flowing through the transformer and, therefore, very little stress on the circuit as the primary protector will absorb almost all of the
surge energy. If Line 2 fires before Line 1, the response will be similar to the one shown, except that the polarities of the voltages and
currents on the load side of the transformer will be reversed. The peak voltages and currents on the load side of the transformer will
be directly proportional to the peak voltage at which the second half of the GDT fires.
OCTOBER 2015 – REVISED JULY 2019
Specifications are subject to change without notice.
Users should verify actual device performance in their specific applications.
The products described herein and this document are subject to specific legal disclaimers as set forth on the last page of this document, and at www.bourns.com/docs/legal/disclaimer.pdf.
TISP4G024L1W
G.Fast
VDSL Protector
3312
- 2 mm SMD
Trimming
Potentiometer
Application Information (Continued)
Longitudinal Surge Response (Continued)
C1
56 nF
LINE 1
1
8
2
7
2026-42-C2LF
3
6
4
5
LINE 2
1:1
25 Ω
1
RL
100 Ω
3
TISP4G024L1W
Transformer
25 Ω
15 Ω
C2
56 nF
10/700 µs Surge Generator
Figure 4. Longitudinal Surge Test Circuit for a G.Fast Application
Load Side Current
28 V
Load Voltage