Target_Datasheet_ICE1HS01G_v0.5_20080901.fm

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ICE1HS01G

Half-Bridge Resonant
Controller

N e v e r   s t o p   t h i n k i n g .

Power Management & Supply

Datasheet, Version 2.0, 24 August 2009

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background image

Edition 24 August 2009

Published by 

Infineon Technologies AG 

81726 Munich, Germany 

© 2007 Infineon Technologies AG 
All Rights Reserved. 

 

Legal Disclaimer 

The information given in this document shall in no event be regarded as a guarantee of 

conditions or characteristics. With respect to any examples or hints given herein, any typical 

values stated herein and/or any information regarding the application of the device, 
Infineon Technologies hereby disclaims any and all warranties and liabilities of any kind, 

including without limitation, warranties of non-infringement of intellectual property rights 

of any third party. 

 

Information 
For further information on technology, delivery terms and conditions and prices, please 

contact the nearest Infineon Technologies Office (

www.infineon.com

). 

 

Warnings 

Due to technical requirements, components may contain dangerous substances. For information 
on the types in question, please contact the nearest Infineon Technologies Office. 

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the express written approval of Infineon Technologies, if a failure of such components can 
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For questions on technology, delivery and prices please contact the Infineon Technologies Offices in Germany or

the Infineon Technologies Companies and Representatives worldwide: see our webpage at http://

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CoolMOS™, CoolSET™ are trademarks of Infineon Technologies AG.

ICE1HS01G

Revision History:

24 August 2009

Target Datasheet

Previous Version:

Page

Subjects (major changes since last revision)

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Type

Package

ICE1HS01G

PG-DSO-8

Version 2.0

3

24 August 2009

ICE1HS01G

Half-Bridge Resonant Controller

PG-DSO-8

ICE1HS01G

Product Highlights

• Minimum number of external components
• High accuracy oscillator
• Two-level over current protection
• Over load/open loop protection
• Mains undervoltage protection with adjustable 

hysteresis

• Adjustable blanking time for over load protection 

and restart

Features

• DSO8 package
• Maximum 600kHz switching frequency
• Adjustable minimum switching frequency with high 

accuracy

• 50% duty cycle
• Mains input under votlage protection with adjustable 

hysteresis

• Two levels of overcurrent protection: frequency shift 

and latch off

• Open-loop/over load protection with extended 

blanking time

• Built-in digital and nonlinear softstart 

• Adjustable restart time during fault protection period

Applications

• LCD/PDP TV
• AC-DC adapter
• Audio SMPS

Typical Application Circuit

C

bus

TL431

R

B1

R

B2

R

C1

C

C2

R

OS2

R

OS1

D

O1

D

O2

C

O

C

f

L

f

V

O

V

INDC

W

P

W

SH

W

SL

FMIN

CS

FB

VINS

GND

LG

HG

VCC

ICE1HS01/G

Auxiliary 

Supply

Driver 

Module

C

C1

R

CS2

R

CS1

D

CS1

D

CS2

C

CS1

C

CS2

C

S

Q

1

Q

2

R

FMIN

R

INS1

R

INS2

C

INS

OPTO

C

FB

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Half-Bridge Resonant Controller

ICE1HS01G

Table of Contents

Page

Version 2.0

4

24 August 2009

1

Pin Configuration and Functionality  . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

1.1

Pin configuration with PG-DSO-8   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

1.2

Pin Functionality   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

2

Representative Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

3

Functional description   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

3.1

Oscillator and Pulse Frequency Modulation   . . . . . . . . . . . . . . . . . . . . . . . . .7

3.2

IC power supply  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

3.3

Soft start   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

3.4

Current sense   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

3.5

Over current protection   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

3.6

Mains Input Voltage Sense  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

3.7

Over load protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

4

Electrical Characteristics  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12

4.1

Absolute Maximum Ratings  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12

4.2

Operating Range  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12

4.3

Characteristics  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13

4.3.1

Supply Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13

4.3.2

Oscillator Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13

4.3.3

Input voltage sense  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14

4.3.4

Current sense   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14

4.3.5

Soft start   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15

4.3.6

Feedback  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  15

4.3.7

Over load protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16

4.3.8

Gate driver  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16

5

Outline Dimension  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17

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Version 2.0

5

24 August 2009

Half-Bridge Resonant Controller

ICE1HS01G

Pin Configuration and Functionality

1

Pin Configuration and
Functionality 

1.1

Pin configuration with PG-DSO-8

Figure 1

Pin configuration with PG-DSO-8

1.2

Pin Functionality

FMIN (minimum switching frequency)
An external resistor is connected between this pin and
the ground. The voltage of this pin is constant during
operation and thus the resistance determines the
current flowing out of this pin. The minimum switching
frequency is determined by this current. The maximum

switching frequency and the switching frequency
during soft start are also related to the current flowing
out of FMIN pin.

CS(current sense)
The current sense signal is fed to this pin. Inside the IC,
two comparators are provided. If the voltage on CS pin
is higher than the first threshold, IC will increase the
switching frequency to limit the maximum output power
of the converter. If the voltage on this pin exceeds the
second threshold, IC will be latched off immediately.

FB (feedback)
This pin is connected to the collector of the opto-
coupler. Internally, during normal operation, this pin is
connected to reference voltage source with a pull-up
resistor(R

FB

). The IC uses the voltage on this pin to

adjust the switching frequency within the range of
maximum and minimum frequency set by FMIN pin. If
FB voltage is higher than V

FBH

 for a certain fixed

blanking time, an extended timer will be started. If over
load/open loop protection exists longer than the
extended blanking time, IC will enter auto-restart mode.
An off timer starts from the instant IC stops switching till
IC starts another soft start. This off time is determined
by the resistors and capacitor connected to VINS pin.

VINS (mains input voltage sense)
The mains input voltage is fed to this pin via a resistive
voltage divider. If the voltage on VINS pin is higher than
the threshold V

INSON

, IC will start to operate with

softstart when VCC increases beyond turn on
threshold. During operation, if the voltage on this pin
falls below the threshold V

INSON

, IC will stop switching

until the voltage on this pin increases again. 
When IC goes into over load protection mode, IC will
stop switching and try to restart after a period of time.
This period can be adjusted by connectting different
capacitors between this pin and ground. 

GND (ground)
IC common ground.

LG (low side gate drive)
Low side power MOSFET driver.

HG (high-side gate drive)
Up side power MOSFET driver.

VCC (IC power supply)
Supply voltage of the IC.

Pin

Symbol

Function

1

FMIN

Minimum switching frequency

2

CS

Current sense

3

FB

Feedback voltage

4

VINS

Input voltage sense

5

GND

IC ground

6

LG

Low side gate drive

7

HG

High side gate drive

8

VCC

IC power supply

1

2

FMIN

3

4

CS

FB

VINS

8

7

6

5

GND

VCC

HG

LG

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Half-Bridge Resonant Controller

ICE1HS01G

Representative Block Diagram

 

Version 2.0

6

24 August 2009

2

Representative Block Diagram

Figure 2

Representative Block Diagram

HG

LG

VC

C

FM

IN

GN

D

FB

CS

Q

FB

2

00ns

En

A

T

OL

P

20

m

s

I

I

RE

F

2

00ns

C

FB

4

EnA

V

FB

_

B

H

C

FB

1

V

FB

_

O

LP

V

FB

_

L

C

FB

5

EnA

V

FB

_

B

L

C

FB

2

EnA

V

FB

_

C

H

C

FB

3

EnA

V

FB

_

C

L

C

V2

EnA

V

VI

_

H

I

vi

_

h

y

s

C

V3

EnA

V

VI

_

L

V

RE

F

I

VI

_c

h

g

C

V1

EnA

V

VI

N

S

50

0

µs

50

µs

T

VI

_R

Ga

te

 D

ri

v

e

r

UV

LO

12

V

11V

Vo

lt

a

g

e

Ref

e

re

nce

Ga

te

 D

ri

v

e

r

C

O1

V

CH

C

O2

V

CL

I

DT

C

FS

cl

k

Q

Q

D

V

RE

F

R

FB

VI

N

S

&

G

FB

1

&

G

FB

2

&

G

V3

&

G

V2

Cur

re

n

t

Li

m

ita

tio

n

5.

0

*

I

ch

g_

m

in

V

RE

F

&

G

V1

&

G

LG

&

G

HG

cl

k

St

a

tus

EnA

&

G

V4

5V

1

G

AR

&

G

L

V

CS

_

La

C

CS1

C

CS2

C

CS3

V

CS

_

H

V

CS

_

L

T

CS_

L

a

V

RE

F

I

CS

C

C

CS

I

CS

D

&

G

O1

&

G

O2

C

CS

5

EnA

V

CS

_

C

L

C

CS5

EnA

V

CS_

C

H

So

ft

 S

ta

rt

Ena

b

le

SS

End

I

RE

F

I

SS

cl

k

OL

P

UP

Re

set

cl

k

Up

/d

o

w

n

I

OCP

I

RE

F

1

G

CS

2

C

F1

V

FM

IN

Q

F1

V

RE

F

R

S

F

FB

2

Q

S

R

F

FB

1

Q

R

S

F

FB

3

Q

S

R

F

FB

4

Q

S

R

F

VI

_

2

Q

Q

S

R

F

La

tc

h

Q

R

S

F

O1

Q

R

S

F

O2

Q

R

S

F

O3

Q

S

R

F

CS_

1

Q

Q

R

S

F

VI

_1

Q

Q

T

OL

P

_

R

&

G

V5

O

v

e

r C

u

rr

e

n

t Pr

ot

e

ct

ion

 (

P

a

te

n

t Pe

n

d

in

g

)

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Version 2.0

7

24 August 2009

Half-Bridge Resonant Controller

ICE1HS01G

Functional description

3

Functional description

The controller ICE1HS01G with two gate outputs is
specially designed for LLC resonant half-bridge
converters. An oscillator with accurately-programmed
frequency range is built inside the IC. The two gate
signals are obtained by passing the signal out from the
oscillator through a divide-by-two flip-flop. Therefore,
two signals are of exactly 50% duty cycle and 180

o

 out

of phase. To guarantee the zero-voltage-switching and
safe operation in half-bridge topologies, a fixed dead
time of 380ns is inserted in each internal when one
switch is turned off and the other is turned on. 
For LLC resonant half-bridge converter, the output
voltage is regulated by changing the switching
frequency. ICE1HS01G offers the designer to choose
suitable operation frequency range by programming
the oscillator with one single resistor. 
In addition, ICE1HS01G offers a programmed soft-start
function to limit both the inrush current and the
overshoot in output voltage.
To protect the system during operation, mains input
under-voltage protection and over-current protection
are integrated in ICE1HS01G as well.

3.1

Oscillator and Pulse Frequency
Modulation

The oscillator is programmed with only one external
resistor R

FMIN

 connected to FMIN pin. The trimmed

capacitor C

FS

 is built inside the IC with high accuracy.

The simplified oscillator circuit is shown in Figure 3. 

Figure 3

Simiplified oscillator circuit

The charge current I

chg

 is sum of four currents which

are I

chg_min

, I

FB

, I

CS

 and I

SS

[1]

Everytime the capacitor C

FS

 is charged by I

chg

 to V

CH

,

the upper switch is turned off and C

FS

 will be

discharged through I

disc

. The charge time determines

the on time for gate signal. The discharge time
determines the dead time during transition from one
gate off to another gate on. The switching waveforms
of the oscillator and gate signals are shown in Figure 4.

Figure 4

Oscillator waveforms

According to Figures 3 and 4, the on time of each gate
can be obtained as

[2]

The switching frequency can be obtained as

[3]

where the dead time T

d

 is fixed as 380ns.

3.1.1

Minimum charge current

The voltage on pin FMIN is a constant of 1.5V during
normal operation. The resistor R

FMIN

 determines the

current(I

FMIN

) flowing out from FMIN pin. Around one-

tenth of I

FMIN

 is defined as the minimum charging

current(I

chg_min

), which in turn defines the minimum

switching frequency as follows.

C

O2

C

O1

V

CH

V

CL

R

S

Q

R

S

Q

FMIN

C

F1

Vdd

Q

F1

I

chg_min

C

FS

I

disc

1.5V

R

FMIN

Q

F2

Q

F3

I

chg

I

FB

I

CS

I

SS

FB

CS

ICE1HS01G

I

chg

I

chgmin

I

FB

I

cs

I

ss

+

+

+

=

V

CF

V

delay

V

LG

V

HG

4V

1V

5V

10V

10V

0V

0V

0V

t

t

t

t

t

d

T

on

3C

FS

I

chg

------------

=

f

s

1

2

3C

FS

I

chg

------------ T

d

+

---------------------------------

=

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Version 2.0

8

24 August 2009

Half-Bridge Resonant Controller

ICE1HS01G

Functional description

Figure 5

FMIN versus R

FMIN

3.1.2

Feedback regulation 

The output information is fed into the controller through
feedback voltage. If the output power is higher, the
feedback voltage will be higher, which will cause the
switching frequency to decrease and vice versa.
The regulation of switching frequency is achieved by
changing the charging current. An accurate operational
transconductance amplifier (OTA) is used to translate
the feedback voltage V

FB

 into current I

FB

. The effective

range of feedback voltage is from 0.9V to 3.9V. 
Figure 6 graphs the relationship between the actual
switching frequency and feedback voltage V

FB

 when

R

FMIN

=22kohm.

Figure 6

Switching frequency versus V

FB

Burst mode operation is also provided by ICE1HS01G.
During LLC operation, the feedback signal V

FB 

is

continuously monitored. When V

FB

 drops below V

FB_off

, the switching signal will be disabled after a fixed
blanking time T

FB

. V

FB

 will then rise as V

out

 starts to

decrease due to no switching signal. Once V

FB 

exceeds

the threshold V

FB_on

, the IC resumes to normal

operation. 

3.1.3

Current sense current I

CS

In LLC resonant topologies, it is necessary to limit the
resonant current in case of short circuit or other fault
conditions. It is achieved by adding another current Ics
to the charging current I

chg

. I

CS

 is limited to 3 times of

the minimum charge current. 

3.1.4

Soft start current I

SS

To limit the inrush current and output overshoot during
start up, the switching frequency shall be necessary
high at start up. The switching frequency will change
gradually toward the minimum switching frequency
until the feedback voltage comes into regulation. The
switching frequency will then go to desired value
according to load and input conditions. The soft start
current I

ss

 also has a upper limit of around 3.4 times of

minimum charge current. Details of soft start will be
shown later.

3.1.5

Charge current I

chg

The charge current I

chg

 for IC oscillator capacitor C

FS

 is

the sum of the four parts including I

chg_min

, I

FB

, I

SS

 and

I

CS

. To limit the maximum switching frequency,

maximum value of I

chg

 is 5 times of I

chg_min

In summary, the maximum charge current during
normal operation is 3I

chg_min

 while the maximum charge

current during fault condition or softstart is around
4I

chg_min 

and 4.43*I

chg_min 

respectively. Figure 7 shows

the maximum switching frequency versus minimum
switching frequency during normal operation. 

Figure 7

Fmax versus Fmin during normal 
operation

0

20

40

60

80

100

120

140

160

180

200

220

240

260

280

0

5 10 15 20 25 30 35 40 45 50 55 60 65

R

FMIN

 [kohm]

Mi

ni

m

u

m

 s

wi

tc

h

ing 

fre

q

uen

cy

 [k

H

z]

50

60

70

80

90

100

110

120

130

140

150

160

170

180

190

200

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

Feedback voltage Vfb [V]

Freq

uency [kHz

]

0

50

100

150

200

250

300

350

400

450

0

25

50

75

100

125

150

175

200

FMIN [kHz]

FM

A

X

 [

k

Hz

]

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background image

 

Version 2.0

9

24 August 2009

Half-Bridge Resonant Controller

ICE1HS01G

Functional description

Figure 8 shows the maximum switching frequency
versus minimum switching frequency during softstart.

Figure 8

Fmax_ss versus Fmin during soft start 

3.2

IC power supply

The controller ICE1HS01G is targetting at applications
with auxiliary power supply. In most cases, a front-end
PFC pre-regulator with a PFC controller is used in the
same system. 
The controller ICE1HS01G starts to operate when the
supply voltage V

VCC

 reaches the on-threshold, V

VCCon

of 12V. The minimum operating voltage after turn-on,
V

VCCoff

, is at 11V. The maximum recommended

operating voltage V

VCCmax

 is 18V. 

3.3

Soft start

At the beginning of the startup phase, the IC provides
a soft start with duration of 32ms with 32 steps. During
this period, the switching frequency is controlled
internally by changing the current I

SS

Figure 9 illustrates the actual switching frequency vs
startup time when R

FMIN

=22kohm. During softstart, the

frequency starts from 250kHz, and step by step drops
to normal operation point.

Figure 9

Switching frequency during softstart 
when R

FMIN

=22kohm

During soft start, the overload protection is disabled
although FB voltage is high.

3.4

Current sense

Current sense in LLC half bridge converters is for
protection purpose. The voltage of resonant capacitor
C

S

 is the sum of the resonant voltage and the dc

voltage which is equal to half of the input bus voltage.
If resonant current is higher, then the voltage on C

S

 is

higher.The current informations for both primary side
and secondary side are almost the same and can be
obtained by dividing and filtering the resonant voltage.
The circuit is shown in Figure 10.

Figure 10

Current sense circuit

3.5

Over current protection

The controller ICE1HS01G incorporates two-level over
current protection. In case of over-load condition, the
lower level OCP will be triggerred, the switching
frequency will be increased according to the duration
and power of the over load. The higher level OCP is
used to protect the converter if transformer winding is
shorted, the IC will be latched immediately.
If V

CS

 is higher than 0.8V, IC will boost up the switching

frequency. If Vcs is lower than 0.75V, IC will resume to
normal operation gradually. If V

CS

 is always higher than

0.8V for 1.5ms, the frequency will rise to its maximum
level. And vice versa.
To sum up, ICE1HS01G will increase the switching
frequency to limit the resonant current in case of
temporary over-load and will also decrease the
switching frequency to its normal value after over-load
condition goes away.

3.6

Mains Input Voltage Sense

The working range of mains input voltage needs to be
specified for LLC resonant converter. It is important for
the controller to have input voltage sensing function
and protection features, which lets the IC stop
switching when the input voltage falls below the
specified range and restarts when the input voltage
increases back within the range. The mains input
voltage sensing circuit is shown Figure 2. With the

0

50

100

150

200

250

300

350

400

450

500

550

0

25

50

75

100

125

150

175

200

FMIN [kHz]

FMA

X

_s

oft sta

rt

 [k

Hz

]

0

50

100

150

200

250

300

0

5

10

15

20

25

30

35

Time [ms]

Frequ

ency [kHz]

R

CS2

R

CS1

D

CS1

D

CS2

C

S

Q

1

Q

2

W

P

C

CS1

V

CS

V

BUS

C

CS2

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background image

 

Version 2.0

10

24 August 2009

Half-Bridge Resonant Controller

ICE1HS01G

Functional description

current source I

hys

 connected between VINS and

Ground, an adjustable hysteresis between the on and
off input voltage can be created as

[4]

The mains input voltage is divided by R

INS1

 and R

INS2

 as

shown in the typical application circuit. A current source
I

hys

 is connected from VINS pin to ground in the IC. If

the on and off threshold for mains voltage is V

mainon

 and

V

mainoff

, the resistors can be decided as

[5]

[6]

3.7

Over load protection

In case of open control loop or output over load fault,
the FB voltage will increase to its maximum level. If FB
voltage is higher than V

FBH

 and this condition last

longer than a fixed blanking time of T

OLP

 (20ms), the IC

will start the extended blanking timer. The extended
blanking timer is realized by charging and discharging
the filter capacitor C

FB

 via the pull up resistor R

FB

 and

Q

FB

. The circuit for extended blanking timer is shown in

Figure 11.

Figure 11

Circuit connected to FB pin

The FB voltage waveform during a OLP period is
shown in Figure 12. After FB voltage has been higher
than V

FBH

 for the fixed blanking time t1 shown in Figure

11, IC will use internal switch Q

FB

 to discharge V

FB

 to

V

FBL

. After the switch Q

FB

 is released, C

FB

 will be

charged up by Vdd through R

FB

. The time needed for

C

FB

 being charged to V

FBH

 can be calculated as

[7]

If C

FB

 is 10nF, the time is about 439us. After V

FB

reaches V

FBH

, an internal counter will increase by 1 and

the capacitor is discharged to 0.5V by Q

FB

 again. The

charging and discharging process of C

FB

 will be

repeated for N

OLP_E

 times if the fault condition still exist.

After the last time of N

OLP_E

 the FB voltage is pulled

down to zero, IC will stop the switch when FB voltage
rises to V

FBH

 again. This is called over load/open loop

proteciton. During the charging and discharging period,
the IC will operate with frequency determined by I

chg_min

and I

CS

Figure 12

FB voltage waveform during over load 
protection

If the converter returns to normal operation during the
extended blanking time period, FB voltage can not
reach V

FBH

 again. Therefore, after FB voltage is

discharged to zero voltage, if it can not reach V

FBH

within T

OLP_R

, IC will reset all the fault timer to zero and

return to normal operation.
After IC enters into OLP, both switches will be stopped.
However, the IC remains active and will try to start with
soft start after an adjustable period. This period is
realized by charging and discharging the capacitor C

INS

connected to VINS pin for N

OLP_R

 times. The time is

therefore determined by the capacitor C

INS

 and resistor

R

INS1

 and R

INS2

. The circuit implementation of the

adjustable off time is shown in Figure 13 and Figure 14
shows the voltage waveform of VINS in this case. 
As shown in Figure 14, the C

INS

 is discharged to V

INS_L

when IC enters into OLP at time t1. After that, an
internal constant current source I

INST

 is turned on to

charge C

INS

. Once the voltage on VINS is charged to

V

INS_H

, the current source will be turned off and C

INS

 is

discharged by another switch Q3 to V

INS_L

 again. The

charging and discharging of C

INS

 is thought as one

cycle. The cylce time is also influenced by the bus

V

HYS

R

INS1

I

hys

=

R

INS1

V

mainon

V

mainoff

I

hys

-------------------------------------------

=

R

INS2

R

INS1

V

INSON

V

mainoff

V

INSON

-------------------------------------------

=

FB

I

1.0V

I

FB

Vdd

R

FB

C

FB1

4.5V

T

OLP

24ms

C

FB3

C

FB2

EnA

EnA

0.5V

S

R

Q

Q

FB

CLK

OLP

UP

Reset

T

OLP_R

1.2ms

S

R

Q

C

FB4

EnA

C

FB5

EnA

0.8V

0.5V

S

R Q

Gate_off

AR

I

ref

S

R

Q

AR_R

ICE1HS01G

t

chg

V

dd

V

FBH

V

dd

V

FBL

---------------------------

ln

R

FB

C

FB

=

V

FB

(V

)

Time

5V

4.5V

t

1

t

2

t

3

0.5V

Maker
Infineon Technologies
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