ICE3AR0680JZ Datasheet, PDF (18/34 Pages) Infineon Technologies AG – Of f -Line SMPS Cur rent Mode Cont rol ler wi th integrated 800V

CoolSET^®-F3R80
ICE3AR0680JZ
Functional Description
VCC Undervoltage
Normal Auto Restart Mode
Short Optocoupler
Normal Auto Restart Mode
Over temperature
Non switch Auto Restart Mode
External protection enable Non switch Auto Restart Mode
3.7.3.1
Vcc OVP, OTP, external protection
enable and Vcc under voltage
BBA
Auto-
restart
Enable
Signal
T_AE ^0.4V
25.5V
C9
Thermal Shutdown
Tj >130°C
120µs blanking
C2
time
Stop
gate
drive
Auto Restart
Mode Reset
VVCC < 10.5V
Spike
Blanking
30µs
Auto Restart
mode
VCC
C1
20.5V
&
4.5V
C4
G1
FBB
softs_period
Voltage
Reference
Control Unit
base pin of an external transistor, T_AE at the BBA pin.
When this function is enabled, it will enter into the non
switch auto restart mode. The gate drive is stopped and
there is no switching pulse before it is recovered
(Figure 29).
The Vcc undervoltage and short opto-coupler will go
into the normal auto restart mode inherently.
In case of VCC undervoltage, the Vcc voltage drops
indefinitely. When it drops below the Vcc under voltage
lock out “OFF” voltage (10.5V), the IC will turn off the
IC and the startup cell will turn on again. Then the Vcc
voltage will be charged up to UVLO “ON” voltage (17V)
and the IC turns on again provided the startup cell
charge up current is not drained by the fault. If the fault
is not removed, the Vcc will continue to drop until it hits
UVLO “OFF” voltage and the restart cycle repeats.
Short Optocoupler can lead to Vcc undervoltage
because once the opto-coupler (transistor side) is
shorted, the feedback voltage will drop to zero and
there will be no switching pulse. Then the Vcc voltage
will drop same as the Vcc undervoltage.
3.7.3.2 Over load, open loop protection
5.0V
Voltage
Reference
Figure 29 Vcc OVP, OTP, external protection
enable
There are 2 types of Vcc over voltage protection; Vcc
OVP (1) and Vcc OVP (2). The Vcc OVP (1) takes
action only during the soft start period. The Vcc OVP
(2) takes the action in any conditions.
Vcc OVP (1) condition is when V_VCC voltage is > 20.5V,
V_FBB voltage is > 4.5V and during soft start period, the
IC enters into odd skip Auto Restart Mode. This
condition likely happens during start up at open loop
fault. (Figure 29).
Vcc OVP (2) condition is when V_VCC voltage is > 25.5V,
the IC enters into odd skip Auto Restart Mode (Figure
29).
The over temperature protection OTP is sensed inside
the controller IC. The Thermal Shutdown block keeps
on monitoring the junction temperature of the
controller. After detecting a junction temperature higher
than 130°C, the IC will enter into the non switch Auto
Restart mode. The F3R80 has also implemented with
a 50°C hysteresis. That means the IC can only be
recovered when the controller junction temperature is
dropped 50°C lower than the over temperature trigger
point (Figure 29).
The external auto restart enable feature can provide a
flexibility to a customer’s self-defined protection
feature. This function can be triggered by pulling down
the V_BBA voltage to < 0.4V. Or it can simply trigger the
Ichg_EB
Auto Restart
Mode Reset
VVCC < 10.5V
S1
R_BO2 ^CBK BBA
#
4.5V _C11
500
C3
0.9V
S2
counter
CT1
Auto
Restart
Mode
Spike
Blanking
30us
&
G5
FBB
C4
4.5V
20ms
Blanking
Time
Control Unit
Figure 30 Over load, open loop protection
In case of Overload or Open Loop, the FBB exceeds
4.5V which will be observed by comparator C4. Then
the built-in blanking time counter starts to count. When
it reaches 20ms, the extended blanking time counter
CT1 is activated. The switch S2 is turned on and the
voltage at the BBA pin will be discharged through 500W
resistor. When it drops to 0.9V, the switch S2 is turned
off and the Switch S1 is turned on. Then a constant
current source I_{chg_EB} will start to charge up BBA pin.
When the voltage hits 4.5V which is monitored by
comparator C11, the switch S1 is turned off and the
Version 2.1a
18
11 Jan 2012