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CRxxxx series
Description
The CR range of protectors are based on the proven
technology of the T10 thyristor product. Designed for
transient voltage protection of telecommunications
equipment, it provides higher power handling than a
conventional avalanche diode (TVS) and when compared to
a GDT offers lower voltage clamping levels and infinite surge
life.
Packaged in a transfer molded DO-214AA surface mount
outline designed for high speed pick & place machines used
in today’s surface mount assembly lines.
Electrical Charecteristics
The electrical characteristics of a CRXXXX device is similar
to that of a self gated Triac, but the CR is a two terminal
device with no gate. The gate function is achieved by an
internal current controlled mechanism.
Like the T.T.S. diodes, the CRXXXX has a standoff voltage
(Vrm) which should be equal to or greater than the operating
voltage of the system to be protected. At this voltage (Vr m)
the current consumption of the CRXXXX is negligible and will
not effect the protected system.
When a transient occurs, the voltage across the CRXXXX
will increase until the breakdown voltage (Vbr) is reached. At
this point the device will operate in a similar way to a T.V.S.
device and is in an avalanche mode.
The voltage of the transient will now be limited and will only
increase by a few volts as the device diver ts more current.
As this transient current rises, a level of current through the
device is reached (Ibo) which causes the device to switch to
a fully conductive state such that the voltage across the
device is now only a few volts (Vt). The voltage at which the
device switches from the avalanche mode to the fully
conductive state (Vt) is known as the Breakover Voltage
(Vbo). When the device is in the Vt state, high currents can
be deverted without damage to the CRXXXX due to the low
voltage across the device, since the limiting factor in such
devices is dissipated power (V x I).
Resetting of the device to the non conducting state is
controlled by the current flowing through the device. When
the current falls below a certain value, known as the Holding
Current (Ih), the device resets automatically.
As with the avalanche T.V.S. device, if the CRXXXX is
subjected to a surge current which is beyond its maximum
rating, then the device will fail in shor t circuit mode, this
ensures that the equipment is ultimately protected.
Selecting A CRXXXX
1.When selecting a CRXXXX device, it is impor tant that the
Vrm of the device is equal to or greater than the operating
voltage of the system.
2.The minimum Holding Current (Ih) must be greater than
the current the system is capable of deliver ing otherwise the
device will remain conducting following a transient condition.
VBR
MIN
VRM VBO
IRM
IBO
I
VT
H
IT
V-I Graph
Illustrating Symbols
and Terms for
the CR Surge
Protection Device.
The CRXXXX Range Can Be Used to Protect Against Surges As Defined In The Following International Standards.
SA SB SC
FCC Rules Part 68/D Metallic 10/560µs 50A 100A 100A
Longitudinal 10/160µs 100A 150A 200A
Bellcore Specification TR-NWT-001089 10/1000µs 37A 75A 100A
2/10µs - - 500A
100v/µs 1KV 1KV 1KV
ITU K-17 (Formerly CCITT) Voltage Wave Form 100/700µs - 1.5KV 1.5KV
Current W ave Form 5/310µs - 38A 38A
VDE 0433 Voltage Wave Form 10/700µs - 2KV 4.0KV
Current W ave Form 5/310µs - 50A 100A
C-NET 131-24 Voltage Wave F rom 0.5/700µs 1.0KV 1.0KV 4.0KV
Current W ave Form 0.8/310µs 25A 25A 100A
IEC 1000-4-5 (Discharge through 2Ωimpendance) I 8/20µs - 100A 250A
Voltage Wave Form 1-2/50µs - 300V 500V
ITU K-20 Voltage Wave Form 10/700µs 1000V 10000V 4000V
(Formerly CCITT) Current W ave Form 5/310µs 25A 25A 100A
53
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CRxxxx series
Specifications
Electrical Charecteristics (Tj=25°C)
SYMBOL PARAMETER SYMBOL PARAMETER
VRM Stand-off Coltage IRM Stand-off Current
VBR Breakdown Voltage IBO Breakover Current
VBO Breako v er Voltage IHHolding Current
VTOn-State Voltage
THERMAL DATA VALUE UNIT
T stg Storage and Operating Junction Temperature range -40 to +150 °C
Tj 150 °C
TL Maximum Temperature For Soldering 230 °C
(For period of 10 seconds max)
Stock Device Reverse Maximum Maximum Maximum Minimum Maximum Typical
Number Code Stand-off Reverse Breakover Breakover Holding On-State Capacitance
Voltage Leakage Voltage Current Current Voltage @1MHz 2v bias
µA @Ibo mA mA @1A pF
CR 0300 SA 030A 25 5 40 800 150 5 100
CR 0640 SA 064A 58 5 77 800 150 5 60
CR 0720 SA 072A 65 5 88 800 150 5 60
CR 0800 SA 080A 75 5 98 800 150 5 60
CR 1100 SA 110A 90 5 130 800 150 5 60
CR 1300 SA 130A 120 5 160 800 150 5 40
CR 1500 SA 150A 140 5 180 800 150 5 40
CR 1800 SA 180A 160 5 220 800 150 5 40
CR 2300 SA 230A 190 5 260 800 150 5 30
CR 2600 SA 260A 220 5 300 800 150 5 30
CR 3100 SA 310A 275 5 350 800 150 5 30
CR 3500 SA 350A 320 5 400 800 150 5 30
CR 0300 SB 030B 25 5 40 800 150 5 100
CR 0640 SB 064B 58 5 77 800 150 5 60
CR 0720 SB 072B 65 5 88 800 150 5 60
CR 0800 SB 080B 75 5 98 800 150 5 60
CR 1100 SB 110B 90 5 130 800 150 5 60
CR 1300 SB 130B 120 5 160 800 150 5 40
CR 1500 SB 150B 140 5 180 800 150 5 40
CR 1800 SB 180B 160 5 220 800 150 5 40
CR 2300 SB 230B 190 5 260 800 150 5 30
CR 2600 SB 260B 220 5 300 800 150 5 30
CR 3100 SB 310B 275 5 350 800 150 5 30
CR 3500 SB 350B 320 5 400 800 150 5 30
CR 0300 SC 030C 25 5 40 800 150 5 200
CR 0640 SC 064C 58 5 77 800 150 5 120
CR 0720 SC 072C 65 5 88 800 150 5 120
CR 0800 SC 080C 75 5 98 800 150 5 120
CR 1100 SC 110C 90 5 130 800 150 5 120
CR 1300 SC 130C 120 5 160 800 150 5 80
CR 1500 SC 150C 140 5 180 800 150 5 80
CR 1800 SC 180C 160 5 220 800 150 5 80
CR 2300 SC 230C 190 5 260 800 150 5 60
CR 2600 SC 260C 220 5 300 800 150 5 60
CR 3100 SC 310C 275 5 350 800 150 5 60
CR 3500 SC 350C 320 5 400 800 150 5 60
MAXIMUM RATINGS
SUFFIX SA
Ipp 10x160µs Amps 100
Ipp 10x560µs Amps 50
ITSM 60Hz Amps 20
DI/dt Amps/µs 500
MAXIMUM RATINGS
SUFFIX SB
Ipp 10x160µs Amps 150
Ipp 10x560µs Amps 100
ITSM 60Hz Amps 30
DI/dt Amps/µs 500
MAXIMUM RATINGS
SUFFIX SC
Ipp 2x10µs Amps 500
Ipp 10x160µs Amps 200
Ipp 10x560µs Amps 100
ITSM 60Hz Amps 60
dI/dt Amps/µs 500
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CRxxxx series
°
°
CRXXXXSB
CRXXXXSC
CRXXXXSA
°
10
100
50
IPP - Percentage peak current - %IPP
2
90
td = 1000µs
tr
tr = 1.25 x (t2 - t1) =10µs
t2
t1
4
13
t - Time - mSec
PULSE WAVE FORM (10/10000µS)
5300200 100050403020 100
10
8
6
5
4
3
2
1
100
80
60
50
40
30
20
143210
Surge Current Duration - full cycles @ 60H
Z
SINUSOIDAL
Peak Current Surge (Non-Repetitive)
CRXXXXSB
CRXXXXSC
CRXXXXSA
On-State Current (RMS) - Amps
PEAK SURGE ON-STATE CURRENT
VS. SURGE CURRENT DURATION
10x160µs PULSE WAVE FORM
Peak Value - Ipp
TEST WAVEFORM
PARAMETER
tr = 10 sec
td = 160 sec
10x160 Waveform
t - Time - Sec
Ipp - Peak Pulse Current - %Ipp
Ipp - Peak Pulse Current - %Ipp
t - Time - Sec
Half Value = Ipp = td
2
80 160 240 320 400 480
10x560µs PULSE WAVE FORM
Peak Value - Ipp
TEST WAVEFORM
PARAMETER
tr = 10 sec
td = 560 sec
10x560 Waveform
Half Value = Ipp = td
2
280
00
560 840 1,120 1,400 1,680
