SMP100MC STMicroelectronics, SMP100MC Datasheet - Page 5

• Manufacturer Part Number: SMP100MC
• Description: TRISIL FOR TELECOM EQUIPMENT PROTECTION
• Manufacturer: STMicroelectronics

Figure 8: Variation of thermal impedance
junction to ambient versus pulse duration
(Printed
recommended pad layout)
APPLICATION NOTE
In wireline applications, analog or digital, both central office and subscriber sides have to be protected.
This function is assumed by a combined series / parallel protection stage.
In such a stage, parallel function is assumed by one or several Trisil, and is used to protect against short
duration surge (lightning). During this kind of surges the Trisil limits the voltage across the device to be
protected at its break over value and then fires. The fuse assumes the series function, and is used to pro-
tect the module against long duration or very high current mains disturbances (50/60Hz). It acts by safe
circuits opening. Lightning surge and mains disturbance surges are defined by standards like GR1089,
FCC part 68, ITU-T K20.
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0
1.E-02
Z
th(j-a)
/R
th(j-a)
1.E-01
circuit
Fuse TCP 1.25A
Typical circuit for subscriber side
1.E+00
Line
board
Ex. Analog line card
tp(s)
1.E+01
FR4,
1.E+02
SCu=35µm,
SMP100MC-xxx
Ring
relay
T1
T2
1.E+03
Ring L
Tip L
Gnd
Figure 9: Relative variation of junction
capacitance versus reverse voltage applied
(typical values)
1.2
1.1
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0
Line
Fuse TCP 1.25A
Fuse TCP 1.25A
Typical circuit for central office side
1
C [V ] / C [V =2V]
Ex. ADSL line card or terminal
R
R
10
V (V)
R
SMP100MC-xxx
SMP100MC-xxx
Tip S
Gnd
Ring S
100
SMP100MC
V
OSC
F =1MHz
Tj = 25°C
= 1V
RMS
5/10
1000