ICE3BR1065J_11 INFINEON [Infineon Technologies AG], ICE3BR1065J_11 Datasheet - Page 17

• Manufacturer Part Number: ICE3BR1065J_11
• Manufacturer: INFINEON [Infineon Technologies AG]

3.7.3
The IC provides Auto Restart Mode as the protection
feature. Auto Restart mode can prevent the SMPS from
destructive states. The following table shows the
relationship between possible system failures and the
corresponding protection modes.
VCC Overvoltage
Overtemperature
Overload
Open Loop
VCC Undervoltage
Short Optocoupler
Auto restart enable
Before entering the Auto Restart protection mode,
some of the protections can have extended blanking
time to delay the protection and some needs to fast
react and will go straight to the protection. Overload
and open loop protection are the one can have
extended blanking time while Vcc Overvoltage, Over
temperature, Vcc Undervoltage, short opto-coupler
and external auto restart enable will go to protection
right away.
After the system enters the Auto-restart mode, the IC
will be off. Since there is no more switching, the Vcc
voltage will drop. When it hits the Vcc turn off threshold,
the start up cell will turn on and the Vcc is charged by
the startup cell current to Vcc turn on threshold. The IC
is on and the startup cell will turn off. At this stage, it will
enter the startup phase (soft start) with switching
cycles. After the Start Up Phase, the fault condition is
checked. If the fault condition persists, the IC will go to
auto restart mode again. If, otherwise, the fault is
removed, normal operation is resumed.
Version 2.0
Protection Modes
Auto Restart Mode
Auto Restart Mode
Auto Restart Mode
Auto Restart Mode
Auto Restart Mode
Auto Restart Mode
Auto Restart Mode
17
3.7.3.1
Figure 25
In case of Overload or Open Loop, the FB exceeds
4.0V which will be observed by comparator C4. Then
the internal blanking counter starts to count. When it
reaches 20ms, the switch S1 is released. Then the
clamped voltage 0.9V at V
is no external capacitor C
reach 4.0V immediately. When both the input signals at
AND gate G5 is positive, the Auto Restart Mode will be
activated after the extra spike blanking time of 30us is
elapsed. However, when an extra blanking time is
needed, it can be achieved by adding an external
capacitor, C
to charge the capacitor C
switch S1 is released. The charging time from 0.9V to
4.0V are the extendable blanking time. If C
and I
52ms and the total blanking time is 72ms. In combining
the FB and blanking time, there is a blanking window
generated which prevents the system to enter Auto
Restart Mode due to large load jumps.
#
C
BK
BK
is 13uA, the extendable blanking time is around
BA
FB
4.0V
4.0V
S1
Auto Restart mode with extended
BK
Auto Restart Mode
. A constant current source of I
blanking time
0.9V
C3
C4
I
BK
G2
1
Functional Description
Blanking
BK
20ms
Time
BA
BK
5.0V
from 0.9V to 4.0V after the
can increase. When there
connected, the V
CoolSET
ICE3BR1065J
G5
&
Blanking
Spike
28 Dec 2011
30us
Control Unit
BK
BK
is 0.22uF
®
Restart
Mode
will start
Auto
-F3R
BA
will