ICE2A280 Infineon Technologies Corporation, ICE2A280 Datasheet - Page 13

• Manufacturer Part Number: ICE2A280
• Manufacturer: Infineon Technologies Corporation

But the Soft-Start Phase must be finished within the
Start Up Phase to force the voltage at pin FB below the
failure detection threshold of 4.8V.
3.8.2
Figure 20 Auto Restart Mode
Figure 20 shows the Auto Restart Mode for open loop
and no load condition. In case of this failure mode the
converter output voltage increases and also VCC. An
additional protection by the comparators C1, C2 and
the AND-gate G1 is implemented to consider this
failure mode (see Figure 21).The overvoltage detection
is provided by Comparator C1 only in the first time
during the Soft-Start Phase till the Soft-Start voltage
exceeds the threshold of the Comparator C2 at 4.0V
and the voltage at pin FB is above 4.8V. When VCC
exceeds 16.5V during the overvoltage detection phase
C1 can set the Error-Latch and the Burst Phase during
Auto Restart Mode is finished earlier. In that case
T
normal operation mode is prevented from overvoltage
Datasheet
Burst2
1 6.5 V
1 3.5 V
D rive r
S o ftS
8.5 V
5 .3V
4 .0V
V C C
4 .8V
F B
is shorter than T
5 µs B la n kin g
O pen loop & no load conditio n
Overvoltage due to open loop with
no load
D ete ction
F ailure
D e te ction P ha se
O v erv olta g e
Soft-Start
S o ft-S ta rt P ha se
O ve rvo ltag e D ete ctio n
T
B urs t2
. By means of C2 the
T
R es ta rt
t
t
t
t
13
detection due to varying of VCC concerning the
regulation of the converter output. When the voltage
V
deactivated.
Figure 21
3.8.3
Thermal Shut Down is latched by the Error-Latch when
junction temperature T
exceeding an internal threshold of 140°C. In that case
the IC switches in Auto Restart Mode.
Note:
SoftS
S o ftS
C
S o ft-S ta rt
is above 4.0V the overvoltage detection by C1 is
All the values which are mentioned in the
functional description are typical. Please refer
to Electrical Characteristics for min/max limit
values.
6 .5 V
Thermal Shut Down
Overvoltage Detection
T 1
R
V C C
S o ft-S ta rt
1 6 .5 V
4 .0 V
Functional Description
j
P o w e r U p R e se t
C 1
C 2
ICE2A165/265/365
of the pwm controller is
CoolSET™-F2
ICE2A180/280
September 2001
G 1
E rro r L a tch