GAS DISCHARGE TUBES (GDTS)
Littelfuse's GDTs (Gas Discharge Tubes) are placed in
front of, and in parallel with, sensitive telecom equipment
such as power lines, communication lines, signal lines
and data transmission lines to help protect them from
damage caused by transient surge voltages that may
result from lightning strikes and equipment switching
operations. These devices do not influence the signal in
normal operation. However, in the event of an overvoltage
surge, such as a lightning strike, the GDT switches to a low
impedance state and diverts the energy away from the
sensitive equipment.
Our GDTs offer a high level of surge protection, a broad
voltage range, low capacitance, and many form factors
including new surface mount devices, which makes them
suitable for applications such as Main Distribution Frame
(MDF) modules, high data-rate telecom applications (e.g.
ADSL, VDSL), and surge protection on power lines. Their low capacitance also results in less signal distortion. When
used in a coordinated circuit protection solution with PolySwitch devices, they can help equipment manufacturers meet
stringent safety regulatory standards.
BENEFITS
• Helps provide overvoltage fault protection against
damage caused by high energy surges
• Suitable for use in sensitive equipment due to
impulse sparkover response
• Suitable for high-frequency applications
• Highly reliable performance
• New surface-mount devices for automated
manufacturing
APPLICATIONS
• Telecommunications
- MDF modules, xDSL equipment, RF systems,
antenna, base stations
• Industrial and Consumer Electronics
- Power supplies, surge protectors, alarm systems,
irrigation systems
FEATURES
• RoHS compliant
• Halogen free
(refers to: Br
≥
900ppm, Cl
≥
900ppm, Br+Cl
≥
1500ppm)
• Wide range of voltages (75V-4000V)
• Wide range of form factors
(3mm, 5mm, 6mm, 7mm, 8mm diameter devices)
• Low capacitance and insertion loss
• Crowbar device with low arc voltage
• High accuracy spark-over voltages for high precision
designs
• Devices tested per ITU K.12 recommendations
• Various lead configurations and surface-mount
options
• Optional fail-short mechanism
• Non radioactive materials
• Devices certified to UL497B and UL1449
RoHS Compliant, ELV Compliant
Specifications subject to change without notice. ©2016 Littelfuse, Inc.
73
Gas Discharge Tubes (GDTs)
Figures G1-G2 — Typical Circuits for Gas Discharge Tubes
Figure G1
Two Electrode Devices forfor Ungrounded Circuits
Two Electrode Devices Ungrounded Circuits
(A) (A)
PolySwitch Device
PolySwitch Device
(A’)(A’)
Figure G2
Three Electrode Devices forfor Grounded Circuits
Three Electrode Devices Grounded Circuits
(A) (A)
PolySwitch Device
PolySwitch Device
(A’)(A’)
Telecom
Telecom
Line
Line
GDT
GDT
Protected
Protected
Equipment
Equipment
Telecom
Telecom
Line
Line
GDT
GDT
Protected
Protected
Equipment
Equipment
(B) (B)
Thyristor
(B’)(B’)
Thyristor
(B) (B)
Thyristors
Thyristors
PolySwitch
PolySwitch
Device
Device
(B’)(B’)
Table G1 — Device Voltage Ratings, Surge Rating, Capacitance, Insulation Resistance
and Agency Approval for Two-Electrode Gas Discharge Tubes
DC
Sparkover
Voltage
Impulse
Sparkover
Voltage
Impulse
Discharge Current
8x20μs
10 Hits
(5 Hits Each
Polarity)
8x20μs
300 Hits
(150 Hits Each
Polarity)
Impulse
Withstanding
Voltage
10/700μs
10 Hits
(5 Times Each
Polarity)
Capacitance
Insulation
Resistance
UL Rating
Part Number
@ 100V/s
± 20% Tolerance
75*
90
140
150
200
230
@ 1kV/μs
600
600
600
600
700
700
900
1000
1000
@1MHz
@100V
DC†
UL497B
#E179610
GTCS23-XXXM-R01-2
1kA
100A
4kV
<0.5pF
1,000 (MΩ)
All Devices
GTCC23-XXXM-R01-2
300
350
400
1kA
100A
6kV
‡
<0.5pF
1,000 (MΩ)
All Devices
* DCSO 60~105
† Devices <=150V measured @ 50V
DC
‡ Effective output impedance: 40ohms
DC
Sparkover
Voltage
Impulse
Sparkover Voltage
DC
Holdover
Voltage
Per
ITU K.12
<52
<52
<80
<80
<135
<135
<135
<135
<150
<150
<150
<150
<150
<150
<150
<150
On-State
Voltage
Nominal
(@1A)
(V)
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
Impulse
Discharge
Current
8x20μs
10 Hits
2.5kA
Impulse
Life
10x1000μs
300 Hits
100A
AC Discharge
Current
(1s duration;
Insulation
10 hits)
Capacitance Resistance
UL Rating
UL497B
#E179610
Part Number
GTCX25-XXXM-R02
@ 100V/s
± 20%
Tolerance @ 100V/μs @ 1kV/μs
75
90
140
150
200
230
250
260
300
350
400
450
450
500
500
600
600
600
700
800
900
900
900
1050
1100
1300
1300
550
550
600
600
700
700
700
800
900
1000
1000
1000
1150
1200
1400
1400
@ 50 Hz
2.5Arms
@ 1MHz
<1pF
@ 100V
DC
10,000 (MΩ) All Devices
GTCX26-XXXM-R05
5kA
100A
5Arms
<1pF
10,000 (MΩ) All Devices
GTCX28-XXXM-R05
5kA
100A
5Arms
<1pF
10,000 (MΩ) All Devices
GTCX28-XXXM-R10
420
470
500
550
600
10kA
100A
10Arms
<1pF
††
10,000 (MΩ) All Devices
GTCX28-XXXM-R20**
20kA
100A
20Arms
<1.5pF
10,000 (MΩ) All Devices
** GTCX28-XXXM-R20 parts only up to 350V
†† <1.2pF for 75V and 90V devices.
74
Specifications subject to change without notice. ©2016 Littelfuse, Inc.
RoHS Compliant, ELV Compliant
Gas Discharge Tubes (GDTs)
Table G2 — Device Voltage Ratings, Surge Rating, Capacitance, Insulation Resistance
and Agency Approval for Two Electrode High-Voltage Gas Discharge
Tubes
DC
Sparkover
Voltage
@100V/s
± 20%
Tolerance
800
1000
1200
1500
(± 15%)
2100
2400
2500
2700
(± 15%)*
3000
3100
(± 15%)*
3600
4000
Impulse
Sparkover
Voltage
Impulse Life
10/1000μs
100A
300 times
N/A
N/A
N/A
N/A
N/A
N/A
300 Times
†
N/A
300 Times
†
N/A
N/A
AC Discharge Current,
50Hz
Multiple Hits
(1s Duration:
10 Hits)
5A
1A
1A
1A
1A
1A
1A
N/A
1A
N/A
1A
1A
Single Hit,
9 Cycles
N/A
5A
5A
5A
5A
5A
5A
N/A
5A
N/A
5A
5A
Impulse
Discharge Current
8/20μs
10 Hits (5 Hits
Each Polarity)
5kA
3kA
3kA
3kA
3kA
3kA
3kA
3kA
3kA
3kA
3kA
3kA
Capacitance
UL Rating
UL1449
#E332226
3
3
3
3
3
3
3
3
3
3
3
3
Part Number
GTCA28-801M-R05
GTCA28-102M-R03
GTCA28-122M-R03
GTCA28-152L-R03
GTCA28-212M-R03
GTCA28-242M-R03
GTCA28-252M-R03
GTCA28-272L-R03
GTCA28-302M-R03
GTCA28-312L
-R03
GTCA28-362M-R03
GTCA28-402M-R03
@ 100V/μs
1400
1700
1900
2200
2700
3300
3500
3700
4000
3700
‡
4600
5000
1 Hit
N/A
10kA
10kA
10kA
10kA
10kA
10kA
10kA
10kA
10kA
10kA
10kA
@ 1MHz
<1pF
<1pF
<1pF
<1pF
<1pF
<1pF
<1pF
<1pF
<1pF
<1pF
<1pF
<1pF
Table G3 — Device Voltage Ratings, Surge Rating, Capacitance, Insulation Resistance
and Agency Approval for Three-Electrode Gas Discharge Tubes
DC
Sparkover
Voltage
(A-E) (B-E)
Impulse
Sparkover Voltage
(A-E) (B-E)
DC
Holdover
Voltage
Per
ITU K.12
<52
<52
<80
<80
<135
<135
<135
<135
<150
<150
<150
<150
<150
<150
<150
<150
Impulse
Discharge
Current
(A+B-E)
8x20μs
10 Hits
5kA
Impulse
Life
(A+B-E)
10x1000μs
300 Hits
100A
AC Discharge
Current
(1s duration;
10 hits)
Insulation
(A+B-E)
Capacitance Resistance
On-State
Voltage
Nominal
(@1A)
(V)
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
20
UL Rating
UL497B
#E179610
Part Number
GTCX35-XXXM-R05
@ 100V/s
± 20%
Tolerance @ 100V/μs @ 1kV/μs
75
90
140
150
200
230
250
260
300
350
400
450
450
500
500
600
600
600
700
800
900
900
900
1050
1100
1300
1300
550
550
600
600
700
700
700
800
900
1000
1000
1000
1150
1200
1400
1400
@ 50 Hz
5Arms
@ 1MHz
<1pF
@ 100V
DC
*
10,000 (MΩ) All Devices
GTCX36-XXXM-R05
5kA
200A
5Arms
<1pF
10,000 (MΩ) All Devices
GTCX36-XXXM-R10
10kA
200A
10Arms
<1pF
10,000 (MΩ) All Devices
GTCX37-XXXM-R10
420
470
500
550
600
10kA
200A
10Arms
<1pF
10,000 (MΩ) All Devices
GTCX38-XXXM-R10
10kA
200A
10Arms
<1pF
10,000 (MΩ) All Devices
* Insulation resistance measured at 50V for devices less than 150V.
Insulation resistance measured at 250V for devices more than 500V.
RoHS Compliant, ELV Compliant
Specifications subject to change without notice. ©2016 Littelfuse, Inc.
75
Gas Discharge Tubes (GDTs)
Figures G3-G11 — Dimensions for Gas Discharge Tubes
Figure G3 — Two Electrode 3mm Product Dimensions
Surface-mount
(GTCS23-XXXM-R01)
ø3
ø3
.0.0
Pad Layout - Surface-mount Devices
(GTCS23-XXXM-R01)
3.0 ± 0.2
3.0 ± 0.2
X
X
Nom
mm
in*
Z1
Y
Z2
Y
Nom
2.0
0.079
Z1
Nom
2.0
0.079
Z2
Nom
2.0
0.079
3.0
0.118
1.0
1.0
1.0
1.0
4.5 ± 0.2
± 0.2
4.5
3.0 ± 0.2
3.0 ± 0.2
* The dimensions in inches are rounded approximations.
Chip GDT
(GTCC23-XXXM-R01)
Pad Layout - Chip GDT Devices
(GTCC23-XXXM-R01)
2.7 ± 0.2
2.7 ± 0.2
X
X
Nom
mm
in*
Z1
Y
Z2
Y
Nom
2.7
0.106
Z1
Nom
2.0
0.079
Z2
Nom
2.0
0.079
3.5
0.138
0.5
0.5
0.5
0.5
4.5 ± 0.3
± 0.3
4.5
3.2 ± 0.2
3.2 ± 0.2
* The dimensions in inches are rounded approximations.
5.0 ± 0.2
(0.197 ± 0.008)
Figure G4 — Two Electrode 5mm Product Dimensions
Axial Leads
(GTCA25-XXXM-R02)
0.5
5.0 ± 0.2
(0.197 ± 0.008)
No Leads
(GTCN25-XXXM-R02)
†
5.00 ± 0.15
(0.197 ± 0.006)
5.0 ± 0.2
(0.197 ± 0.008)
5.00 ± 0.15
(0.197 ± 0.006)
Surface-mount
(GTCS25-XXXM-R02)
5.00 ± 0.15
(0.197 ± 0.006)
± 0.2
± 0.008)
0.5
(0.020)REF
ø0.8
(0.032)REF ± 0.2
5.0
(0.197 ± 0.008)
5.0 ± 0.2
(0.197 ± 0.008)
5.0 ± 0.2
(0.197 ± 0.008)
4.4 ± 0.2
(0.173 ± 0.008)
0.5
(0.020)REF
ø0.8
(0.032)REF
5.0 ± 0.2
(0.197 ± 0.008)
Pad Layout - Surface-mount Devices
(GTCS25-XXXM-R02)
Y
X
X
Nom
mm
in*
Z
Y
Nom
3.9
0.154
Z
Nom
1.3
0.051
Y
6.0
0.236
Y
* The dimensions in inches are rounded approximations.
† Parts with no leads are not solderable and are meant for insertion into magazine clips.
X
X
Z
Z
76
Specifications subject to change without notice. ©2016 Littelfuse, Inc.
RoHS Compliant, ELV Compliant
5.0 ± 0.2
(0.197 ± 0.008)
5.0 ± 0.2
(0.197 ± 0.008)
(0.020)REF
60.0 ± 4.0
4.4 ± 0.2
5.0 ± 0.2
(0.173 ± 0.008) (2.364 ± 0.158) (0.197 ± 0.008)
ø0.8
60.0 ± 4.0
(0.032)REF
(2.364 ± 0.158)
Gas Discharge Tubes (GDTs)
Figures G3-G11 — Dimensions for Gas Discharge Tubes
ø6.0 ± 0.2
(0.236 ± 0.008)
6.2 ± 0.2
(0.244 ± 0.008)
Figure G5 — Two Electrode 6mm Product Dimensions
(0.165 ± 0.008)
62.0 ± 2.0
(2.441 ± 0.079)
6.2 ± 0.2
(0.244 ± 0.008)
0.6
Axial Leads
(0.024)REF
6.2
(GTCA26-XXXM-R05)
± 0.2
4.2 ± 0.2
(0.244 ± 0.008)
No Leads
(GTCN26-XXXM-R05)
†
ø6.0 ± 0.2
(0.236 ± 0.008)
ø6.0 ± 0.2
(0.236 ± 0.008)
(Cont’d)
4.2 ± 0.2
(0.165 ± 0.008)
Surface-mount
(GTCS26-XXXM-R05)
ø6.0 ± 0.2
(0.236 ± 0.008)
6.2 ± 0.2
(0.244 ± 0.008)
62.0 ± 2.0
(2.441 ± 0.079)
ø6.0 ± 0.2
(0.236 ± 0.008)
ø6.0 ± 0.2
(0.236 ± 0.008)
0.6
(0.024)REF
ø0.8
(0.032)REF
6.2 ± 0.2
(0.244 ± 0.008)
08)
ø0.8
6.2 ± 0.2
(0.032)REF
(0.244 ± 0.008)
4.2 ± 0.2
(0.165 ± 0.008)
4.2 ± 0.2
(0.165 ± 0.008)
4.2 ± 0.2
(0.165 ± 0.008)
0.6
(0.024)REF
4.2 ± 0.2
(0.165 ± 0.008)
Pad Layout - Surface-mount Devices
(GTCS26-XXXM-R05)
Y
X
Nom
X
Y
Nom
3.7
0.146
Z
Nom
1.3
0.051
mm
in*
Z
8.2 ± 0.2
(0.323 ± 0.008)
ø8.0 ± 0.2
(0.315 ± 0.008)
7.0
0.276
Figure G6 — Two Electrode 8mm Product Dimensions
Z
0.5
Axial Leads
(0.02)REF
8.2 ± 0.2
6.0 ± 0.2
(GTCA28-XXXM-R05, R10 &
±
R20)
(0.323 0.008)
(0.236 ± 0.008)
8.2 ± 0.2
(0.323 ± 0.008)
62.0 ± 4.0
(2.441 ± 0.157)
X
0.5
No Leads
Surface-mount
(0.02)REF
6.0 ± 0.2
(GTCN28-XXXM-R05, R10 & R20)
†
(0.236 ± 0.008)
(GTCS28-XXXM-R05, R10 & R20)
Z
ø8.0 ± 0.2
(0.315 ± 0.008)
8.2 ± 0.2
(0.323 ± 0.008)
ø8.0 ± 0.2
(0.315 ± 0.008)
ø8.0 ± 0.2
(0.315 ± 0.008)
Y
* The dimensions in inches are rounded approximations.
† Parts with no leads are not solderable and are meant for insertion into magazine clips.
Y
62.0 ± 4.0
(2.441 ± 0.157)
ø8.0 ± 0.2
(0.315 ± 0.008)
ø8.0 ± 0.2
(0.315 ± 0.008)
0.5
(0.02)REF
8)
ø0.8
(0.032)REF
8.2 ± 0.2
(0.323 ± 0.008)
6.0 ± 0.2
(0.236 ± 0.008)
0.5
(0.02)REF
6.0 ± 0.2
(0.236 ± 0.008)
ø0.8
(0.032)REF
8.2 ± 0.2
(0.323 ± 0.008)
6.0 ± 0.2
(0.236 ± 0.008)
6.0 ± 0.2
(0.236 ± 0.008)
0.5
(0.02)REF
Pad Layout - Surface-mount Devices
(GTCS28-XXXM-R05, R10 & R20)
Y
X
Nom
X
Y
Nom
5.6
0.22
Z
Nom
1.2
0.047
mm
in*
Z
9.0
0.354
Y
* The dimensions in inches are rounded approximations.
† Parts with no leads are not solderable and are meant for insertion into magazine clips.
Y
Figure G7 — Two Electrode 8mm High Voltage Product Dimensions
X
Z
Axial Leads
(GTCA28-XXXM-R0X)
ø8 ± 0.2
ø0.8
Z
6 ± 0.2
62 ± 4
RoHS Compliant, ELV Compliant
Specifications subject to change without notice. ©2016 Littelfuse, Inc.
77
ø8.0 ± 0.2