ICE3AR0680JZ Datasheet, PDF (20/34 Pages) Infineon Technologies AG – Of f -Line SMPS Cur rent Mode Cont rol ler wi th integrated 800V

CoolSET^®-F3R80
ICE3AR0680JZ
Functional Description
turn on with soft start in the coming restart cycle when
Vcc reaches the Vcc “ON” voltage 17V.
When there is an input voltage drop, the BBA voltage
also drops. When the voltage at BBA pin falls below
0.9V, the output of OPAMP C14 is changed to high.
The inverter gate G22 will change the high input to low
output. Then the NAND gate G22 will have a high
output. The negative output of the flip flop FF5 is then
become high. The constant load LD6 is “ON” again and
the IC enters the brownout mode where the Vcc swings
between 10.5V and 17V without any switching pulse.
The formula to calculate the R_BO1 and R_BO2 are as
below.
R_BO1=V_hys/I_{chg_BO}
R_BO2=V_{ref_BO}*R_BO1/(V_{BO_l} -V_{ref_BO})
where V_{BO_l}: input brownout voltage (low point); V_hys:
input brownout hysteresis voltage; V_{ref_BO}: IC reference
voltage for brownout; R_BO1 and R_BO2: resistors divider
from input voltage to BBA pin
For example,
I_{chg_BO}=10uA, V_{ref_BO}=0.9V,
Case 1:
if brownout voltage is 70Vac on and 100Vac off,
then brownout voltage, V_{BO_l}=100Vdc,
hysteresis voltage, V_{BO_hys}=43Vdc,
R_BO1=4.3MW, R_BO2=39KW
Case 2:
if brownout voltage is 100Vac on and 120Vac off,
then brownout voltage, V_{BO_l}=141Vdc,
hysteresis voltage, V_{BO_hys}=28Vdc,
R_BO1=2.8MW, R_BO2=18KW
Case 3:
if brownout voltage is 120Vac on and 160Vac off,
then brownout voltage, V_{BO_l}=169Vdc,
hysteresis voltage, V_{BO_hys}=56Vdc,
R_BO1=5.6MW, R_BO2=30KW
The summary is listed below.
Note: The above calculation assumes the tapping point
(bulk capacitor) has a stable voltage with no ripple
voltage. If there is ripple in the input voltage, it should
take the highest voltage for the calculation; V_{BO_l} +
ripple voltage. Besides that the low side brownout
voltage V_{BO_l} added with the ripple voltage at the
tapping point should always be lower than the high side
brownout voltage (V_{BO_h}); V_{BO_h} > V_{BO_l} + ripple
voltage. Otherwise, the brownout feature cannot work
properly. In short, when there is a high load running in
system before entering brownout, the input ripple
voltage will increase and the brownout voltage will
increase (V_{BO_l} = V_{BO_l} + ripple voltage) at the same
time. If the V_{BO_hys} is set too small and is close to the
ripple voltage, then the brownout feature cannot work
properly (V_{BO_l} = V_{BO_h}).
If the brownout feature is not needed, it needs to tie the
BBA pin to the Vcc pin through a current limiting
resistor, 500KW~1MW. The BBA pin cannot be in
floating condition. If the brownout feature is disabled
with a tie up resistor, there is a limitation of the
capacitor C_BK at the BBA pin. It is as below.
Vcc tie up resistor
1
500KW
2
1MW
C_{BK_max}
0.47uF
0.22uF
3.7.5
Action sequence at BBA pin
Since there are 3 functions at the same BBA pin;
brownout, extended blanking time and the auto-restart
enable, the actions of sequence are set as per the
below table in case of several features happens
simultaneously.
1st Auto-restart
2nd
enable
Auto-restart
enable
Auto-restart
enable
Extended
Auto-restart
blanking time enable
Brownout
Auto-restart
enable
Extended
blanking time
Auto-restart
enable
Extended
blanking time
Extended
blanking time
Brownout
Brownout
Brownout
Brownout
The top row of the table is the first happened feature
and the left column is the second happened feature.
For example,
Case
1
2
3
V_{BO_l}
100V
141V
169V
V_{BO_h}
143V
169V
225V
V_{BO_hys}
43V
28V
56V
R_BO1
4.3MW
2.8MW
5.6MW
R_BO2
39KW
18KW
30KW
Case 1:
The “Auto-restart enable” feature happened first and it
follows with the “Extended blanking time” feature. Then
the “Auto-restart enable” feature will continue to hold
and the “Extended blanking time” feature is ignored.
Version 2.1a
20
11 Jan 2012