ICE2AS01_06 INFINEON [Infineon Technologies AG], ICE2AS01_06 Datasheet - Page 7

• Manufacturer Part Number: ICE2AS01_06
• Description: Off-Line SMPS Current Mode Controller
• Manufacturer: INFINEON [Infineon Technologies AG]

3
3.1
Figure 3
The Undervoltage Lockout monitors the external
supply voltage V
current consumption is max. 55µA. When the SMPS is
plugged to the main line the current through R
charges the external Capacitor C
exceeds the on-threshold V
circuit and the voltage reference are switched on. After
it the internal bandgap generates a reference voltage
V
uncontrolled ringing at switch-on a hysteresis is
implemented which means that switch-off is only after
active mode when Vcc falls below 8.5V.
In case of switch-on a Power Up Reset is done by
reseting the internal error-latch in the protection unit.
When V
internal reference is switched off and the Power Down
reset let T1 discharging the soft-start capacitor C
at pin SoftS. Thus it is ensured that at every switch-on
the voltage ramp at pin SoftS starts at zero.
Datasheet
Preliminary Data
REF
=6.5V to supply the internal circuits. To avoid
VCC
C
SoftS
VCC
Soft-Start
8.5V
Functional Description
Power Management
falls below the off-threshold V
Undervoltage
Power-Up
Power Management
Power-Down
Reset
Lockout
Reset
T1
R
6.5V
VCC
13.5V
Soft-Start
Power Management
. In case the IC is inactive the
R
Main Line (100V-380V)
Start-Up
C
CCon
VCC
Error-Latch
R
S
Reference
Voltage
Internal
=13.5V the internal bias
Bias
Q
Q
Error-Detection
Soft-Start Comparator
Primary Winding
VCC
PWM-Latch
. When V
CCoff
6.5V
5.3V
4.8V
4.0V
=8.5V the
Soft-Start
Start-up
VCC
7
3.2
Figure 4
Current Mode means that the duty cycle is controlled
by the slope of the primary current. This is done by
comparison the FB signal with the amplified current
sense signal.
Figure 5
In case the amplified current sense signal exceeds the
FB signal the on-time T
reseting the PWM-Latch (see Figure 5).
0.8V
Driver
FB
Amplified Current Signal
FB
Soft-Start Comparator
Improved
Current Mode
Improved Current Mode
Current Mode
Pulse Width Modulation
0.8V
T
PWM OP
on
PWM Comparator
x3.65
Functional Description
on
of the driver is finished by
ICE2AS01/S01G
ICE2BS01/S01G
PWM-Latch
R
S
Isense
30 Jun 2006
Q
Q
Driver
t
t