©2009 Littelfuse, Inc.
Gas Discharge Tube (GDT) Products
19
Revised: November 10, 2009
Specifications are subject to change without notice.
Please refer to www.littelfuse.com for current information.
Customer should verify actual device performance in their specific applications.
SL1021A/B, SL1024A/B and PMT8 Series
SL1021A/B, SL1024A/B and PMT8 Series
Description
GDT circuit protection devices dissipate electrical
surge energy safely within a contained plasma gas.
Commonly used to help protect sensitive telecom and
networking equipment and lines, GDTs protect from
damage that may result from lightning strikes and
equipment switching operations.
The Littelfuse GDT series described in this document
are available in a variety of leaded and surface mount
forms and offered with and without optional fail-
safe clip. Please refer to the electrical specifications,
dimension and packaging options section of this
document for additional information.
SL1021A/B and SL1024A/B Series:
SL1021A/B and SL1024A/B series GDTs are designed
to offer high levels of performance on fast rising
transients in the range of 100V/S to 1KV/S, which
are those most likely created by induced lightning
disturbances.
These devices feature ultra low capacitance (typically
1.5pF or less) and are extremely robust with SL102xA
devices able to divert a 10,000 Amp pulse without
destruction, and SL102xB suffix devices able to divert
a 20,000 Amp pulse without destruction.
These series offer optimized internal geometry which
provide low insertion loss at high frequencies, ideal
for the protection of broadband and other high speed
transmission equipment.
PMT8 Series:
PMT8 GDT's are telecom grade devices designed to
meet the recommendations in CCITT-K12 and Bellcore
GR-1361-CORE. The three electrode configuration
is used in applications where simultaneous crowbar
action of two signal lines is required.
Features
• RoHS compliant
• Low insertion loss
• Excellent response to
fast rising transients
• Ultra low capacitance
• 10KA (A suffix devices) /
20KA (B suffix devices)
surge capability tested
with 8/20s pulse as
defined by IEC 61000-4-5
• Available with thermal
failsafe option (add ‘F’
suffix to part number)
Applications
SL1021 / SL1024:
• Broadband equipment
• ADSL equipment
• XDSL equipment
• Satellite and CATV
equipment
• Splitters
• General telecom
equipment
PMT8:
• Telecom network
interfaces
• Telephone line cards
• Repeaters
• Modems
• Line test equipment
SL1021A/B, SL1024A/B and PMT8 Series
AGENCY AGENCY FILE NUMBER
®E128662
Agency Approvals
3 Electrode GDT Graphical Symbol
a
e
ba = TIP
b = RING
e = GROUND
(center electrode)
®
Product Characteristics
Materials Dull Tin Plate 17.5 ± 12.5 Microns.
with ceramic insulator
Product Marking
‘LF’ mark, voltage& date code:
SL102xA - Red/White text
SL102xB & PMT8 - Blue/White text
Glow to arc
transition current ~ 1Amp
Glow Voltage
~60-200 Volts
Storage and Operation
Temperature
-40 to +90°C
Transverse Voltage
(Delay Time)
< 0.2µSec (Tested to ITU-T Rec. K.12)
Arc Voltage
~10 to 35 Volts
Holdover Voltage
<150mS (Tested to ITU-T Rec. K.12)
©2009 Littelfuse, Inc.
Gas Discharge Tube (GDT) Products
20
Revised: November 10, 2009 Specifications are subject to change without notice.
Please refer to www.littelfuse.com for current information.
Customer should verify actual device performance in their specific applications.
SL1021A/B, SL1024A/B and PMT8 Series
SL1021A/B, SL1024A/B and PMT8 Series
Electrical Characteristics
Device Specifications (at 25°C) Life Ratings
Part
Number*
DC Voltage
100V/Sec.
DC
Voltage
100 V/
Sec.
DC
Voltage
1kV/
Sec.
Capaci-
tance
(@1Mhz)
Insulation
Resistance
AC
Current
50Hz
1Sec.x101
Surge
Current
8/20Sec
x101
Max
Single
Surge
8/20Sec1
Max Single
Surge
10/350Sec1
Surge Life
10/1000
Secx3001
MIN TYP MAX MIN
SL1021A090
SL1024A090
SL1021B090
SL1024B090
PMT 8 090
72 90 108
500
650
<1.5pF


10Amps 10kA2
20kA3
15kA2
25kA3
4kA2
5kA3
200Amps
SL1021A145
SL1024A145
SL1021B145
SL1024B145
116 145 174
600


2.5kA2
5kA3
SL1021A150
SL1024A150
SL1021B150
SL1024B150
120 150 180
SL1021A200 150 200 250
SL1021A230
SL1024A230
SL1021B230
SL1024B230
PMT 8 230
184 230 276 450
650
SL1021A250
SL1024A250
SL1021B250
SL1024B250
PMT 8 250
200 250 300 500
SL1021A260
SL1024A260
SL1021B260
SL1024B260
210 260 310 550 700
SL1021A300
SL1024A300
SL1021B300
SL1024B300
240 300 360 650 850
SL1021A350
SL1024A350
SL1021B350
SL1024B350
PMT 8 350
280 350 420 700 900
SL1021A400
SL1024A400
SL1021B400
SL1024B400
PMT 8 400
320 400 480
850 950
SL1021A420
SL1024A420
SL1021B420
SL1024B420
345 420 500
SL1021A450
SL1024A450
SL1021B450
SL1024B450
360 450 540 900 1000
SL1021A500
SL1024A500
SL1021B500
SL1024B500
400 500 600 950 1100
SL1021A600
SL1024A600 480 600 720 1000 1200
NOTES:
*Max capacitance is 1.5 pF, measured at 1 MHz.
1. Total current through centre electrode, tested in accordance with ITU-T Rec K.12
2. SL A series
3. SL B series & PMT 8 series
©2009 Littelfuse, Inc.
Gas Discharge Tube (GDT) Products
21
Revised: November 10, 2009
Specifications are subject to change without notice.
Please refer to www.littelfuse.com for current information.
Customer should verify actual device performance in their specific applications.
SL1021A/B, SL1024A/B and PMT8 Series
SL1021A/B, SL1024A/B and PMT8 Series
Time vs. Current for Failsafe
0.5
1
2
3
4
5
6
7
8
9
11
12
13
14
15
10
20
30
60
12 5 10 15 30
SL102xA with Failsafe
SL102xB or PMT8 500 Volt Higher Melting Point Solder
SL102xB or PMT8 90 Volt Higher Melting Point Solder
SL102xB or PMT8 350 Volt Higher Melting Point Solder
Voltage vs. Time Characteristic
Voltage
(V)
Time (ns)
0 200 400 600 800 1000 1200
Max dynamic breakover
voltage
Hold-over voltage
On-State voltage
Reflow Condition Pb – Free assembly
Pre Heat
- Temperature Min (Ts(min))150°C
- Temperature Max (Ts(max))200°C
- Time (Min to Max) (ts)60 – 180 secs
Average ramp up rate (Liquidus Temp
(TL) to peak 3°C/second max
TS(max) to TL - Ramp-up Rate 5°C/second max
Reflow - Temperature (TL) (Liquidus) 217°C
- Temperature (tL)60 – 150 seconds
Peak Temperature (TP)260+0/-5 °C
Time within 5°C of actual peak
Temperature (tp)10 – 30 seconds
Ramp-down Rate 6°C/second max
Time 25°C to peak Temperature (TP)8 minutes Max.
Do not exceed 260°C
Soldering Parameters - Reflow Soldering (Surface Mount Devices)
Time
Temperature
TP
TL
TS(max)
TS(min)
25
tP
tL
tS
time to peak temperature
(t 25ºC to peak)
Ramp-down
Ramp-up
Preheat
Critical Zone
TL to TP
Soldering Parameters - Wave Soldering (Thru-Hole Devices)
Soldering Parameters - Hand Soldering
Dwell Time
0
20
40
60
80
100
120
140
160
180
200
220
240
260
280
300
0
10
20
30
40
50
60
70
80
90
100
110
120
130
140
150
160
170
180
190
200
210
220
230
240
Time (Seconds)
Temperature (°C) - Measured on bottom side of board
Cooling Time
Preheat Time
Wave Parameter Lead-Free Recommendation
Preheat:
(Depends on Flux Activation Temperature) (Typical Industry Recommendation)
Temperature Minimum: 100° C
Temperature Maximum: 150° C
Preheat Time: 60-180 seconds
Solder Pot Temperature: 280° C Maximum
Solder Dwell Time: 2-5 seconds
Recommended Process Parameters:
Solder Iron Temperature: 350° C +/- 5°C
Heating Time: 5 seconds max.
Note: Surge Arrestors with a Failsafe mechanism should be
individually examined after soldering
©2009 Littelfuse, Inc.
Gas Discharge Tube (GDT) Products
22
Revised: November 10, 2009 Specifications are subject to change without notice.
Please refer to www.littelfuse.com for current information.
Customer should verify actual device performance in their specific applications.
SL1021A/B, SL1024A/B and PMT8 Series
SL1021A/B, SL1024A/B and PMT8 Series
8.1
[0.319]
10.10
[0.398]
9.9
[0.354]
9.9
[0.354]
10.10
[0.398]
4.4± 0.3
[0.173± 0.12]
4.4± 0.3
[0.173± 0.12]
15
[0.590]
16.8
[0.661]
4.4
[0.173]
1.0 DIA. MAX.
[0.039]
12.4 ± 1
[0.488 ± 0.039]
11.8
[0.464]
11.8
[0.464]
8.1.
[0.319]
9.9
[0.354]
16.8
[0.661]
11.8
[0.464]
6.35 ± 0.5
[0.25 ± 0.25]
15
[0.590]
1.0 DIA. MAX.
[0.039]
8.1 DIA. MAX.
[0.319]
10.10
[0.398]
14.7
[0.579]
6.35 ± 0.5
[0.25 ± 0.25]
9.0
[0.354]
0.3mm
Minimum
Gap
0.3mm
Minimum
Gap
0.3mm
Minimum
Gap
Mounting Area
9.0
[0.354]
Mounting Area
9.0
[0.354]
Mounting Area
9.9
[0.354]
10.10
[0.398]
5.5± 0.3
[0.216± 0.12]
5.5± 0.3
[0.216± 0.12]
15
[0.590]
16.8
[0.661]
4.4
[0.173]
1.0 DIA. MAX.
[0.039]
12.4 ± 1
[0.488 ± 0.039]
11.8
[0.464]
8.1.
[0.319]
0.3mm
Minimum
Gap
9.0
[0.354]
Mounting Area
10.10
[0.398]
22
[0.866] 1.0 DIA. MAX.
[0.039]
50 ± 3
[1.968 ± 0.118 ]
8.1 DIA. MAX.
[0.319]
11.8
[0.464]
23.8
[0.937]
9.0
[0.354]
Mounting Area
0.3mm
Minimum
Gap
Type 01 / C
Type 60
Type 06 / Y
Type 14 / X
Type 04 / R
Type 05 / P
PROFILE VIEW
SOLDERING PAD LAYOUT
SIDE VIEW TOP VIEW
7.7 ± 0.3
[0.303 ± 0.019]
10.0 ± 0.3
[0.394 ± 0.019]
Ø7.0 ± 0.1
[0.275 ± 0.004]
8.3 +0.3/-0.0
[0.327
+0.019/-0.00]
8.0 +0.3/-0.1
[0.315
+0.019/-0.004]
8.5 ± 0.0
[0.335 ± 0.000]
2.2 ± 0.0
[0.087 ± 0.000]
6.0 ± 0.0
[0.236 ± 0.000]
10.75 ± 0.0
[0.423 ± 0.000]
1.2 ± 0.0
[0.047 ± 0.000]
1.2 ± 0.0
[0.047 ± 0.000]
Overall Product Space
DO NOT ENCROACH
Device Dimensions
NOTE: Failsafe option dimensions shown in green.
Shaped Radial Leaded Devices: Surface Mount Devices:
Straight Radial Leaded Devices:
Straight "T" Leaded Devices:
©2009 Littelfuse, Inc.
Gas Discharge Tube (GDT) Products
23
Revised: November 10, 2009
Specifications are subject to change without notice.
Please refer to www.littelfuse.com for current information.
Customer should verify actual device performance in their specific applications.
SL1021A/B, SL1024A/B and PMT8 Series
SL1021A/B, SL1024A/B and PMT8 Series
Packaging
Part Numbering System and Ordering Information
PMT8 xxx x x
Breakdown Voltage
090 = 90V
230 = 230V
250 = 250V
350 = 350V
400 = 400V
Breakdown Voltage
090 = 90V
145 = 145V
150 = 150V
200 = 200V
230 = 230V
250 = 250V
260 = 260V
300 = 300V
350 = 350V
400 = 400V
420 = 420V
450 = 450V
500 = 500V
600 = 600V
Series
PMT8
Configuration Code
Option Code
Blank = No Failsafe
F = With Failsafe
SL102x x xxx x x
Series
SL1021
SL1024
Surge Capability
A = 10kA
B = 20kA
Configuration Code
(See Device Dimensions section) (See Device Dimensions section)
C
R
P
01
04
05
06
Y
S
X
10
14
60
Blank = No failsafe
F or G = With Failsafe
Option Code
Device Type Description Quantity
Type 01 / C 100pcs/tray x 5 trays per carton 500
Type 04 / R 100pcs/tray x 5 trays per carton 500
Type 05 / P 100pcs/tray x 5 trays per carton 500
Type 06 / Y 100pcs/tray x 5 trays per carton 500
Type 14 / X 50pcs/tray x 5 trays per carton 250
Type 60 500pcs/reel* x 10 reels per carton 5000
* For tape and reel specifications, please contact factory.