D at a s he e t V e rs io n 2 .2 , 0 4 J u l 2 0 1 1
Po wer Ma na ge me nt & Su p ply
N e v e r
s t o p
t h i n k i n g .
ICE2QS01
Revision History:
04 Jul 2011
Previous Version:
2.1
Page
Subjects (major changes since last revision)
16
revised outline dimension.
Datasheet
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Edition 2011-07-04
Published by
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© 2007 Infineon Technologies AG
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ICE2QS01
Quasi-Resonant PWM Controller
ICE2QS01
PG-DIP-8
Product Highlights
• Active burst mode for low standby power
• Digital frequency reduction for better overall
system efficiency
• Integrated power cell for IC self-power supply
PG-DIP-8
Features
Description
•
•
ICE2QS01 is a quasi-resonant PWM controller
optimized for off-line switch power supply applications
such as LCD TV, CRT TV and notebook adapter. The
digital frequency reduction with decreasing load
enables a quasi-resonant operation till very low load.
As a result, the system efficiency is significantly
improved compared to other conventional solutions.
The active burst mode operation enables an ultra-low
power consumption at standby mode with small and
controllable output voltage ripple. The innovative
power cell solves the IC power supply problem when
the output voltage is pulled down during standby
mode, or during latch-off mode. The numerous
protection functions give a full protection of the power
supply system in failure situations. All of these make
the ICE2QS01 an outstanding controller for quasiresonant flyback converter in the market.
•
•
•
•
•
•
•
•
•
Quasiresonant operation till very low load
Active burst mode operation at light load for low
standby input power (< 1W)
Digital frequency reduction with decreasing load
Power cell for VCC pre-charging and IC power supply
during latch-off, or standby mode operation when it is
necessary
Built-in digital soft-start
Foldback correction and cycle-by-cycle peak current
limitation
Auto restart mode for VCC Overvoltage protection
Auto restart mode for VCC Undervoltage protection
Auto restart mode for openloop/overload protection
Latch-off mode for adjustable output overvoltage
protection
Latch-off mode for Short-winding protection
Typical Application
85 ~ 265 VAC
RVCC
CZC
GND
CPS
Q1
Active Burst Mode
REG
Gate
Driver
Rb2
Optocoupler
Current
Limitation
RCS
ICE2QS01
ICE2QS01
Version 2.2
CS
Rovs1
Rc1
Protection Block
Current Mode Control
Type
Rb1
CDS
OUT
Power Management
Digital Process Block
CREG
Wa
DZC
ZC
Power
Cell
Zero Crossing Detection
VO
Cf
RZC1
Dr1~Dr4
PWM
Controller
Lf
DO
CO
RZC2
VCC
Ws
DVCC
CVCC
HV
Wp
Snubber
Cbus
TL431
Cc2
Rovs2
Marking
Package
ICE2QS01
PG-DIP-8
3
Cc1
4 Jul 2011
Quasi-Resonant PWM Controller
ICE2QS01
Table of Contents
Page
1
Pin Configuration and Functionality . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
1.1
Pin Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
1.2
Package PG-DIP-8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
1.3
Pin Functionality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
2
Representative Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
3
3.1
3.2
3.3
3.3.1
3.3.2
3.3.3
3.4
3.4.1
3.4.2
3.4.3
3.4.4
3.5
Functional Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
VCC Pre-Charging and Typical VCC Voltage During Start-up . . . . . . . . . . . .7
Soft-start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Normal Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Switch-on Determination. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Switch-off Determination. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Foldback Point Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Active Burst Mode Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Entering Active Burst Mode Operation . . . . . . . . . . . . . . . . . . . . . . . . . . .10
During Active Burst Mode Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Leaving Active Burst Mode Operation . . . . . . . . . . . . . . . . . . . . . . . . . . .10
IC Power Supply During Active Burst Moe Operation . . . . . . . . . . . . . . .10
Protection Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
4
4.1
4.2
4.3
4.3.1
4.3.2
4.3.3
4.3.4
Electrical Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Operating Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Supply Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
PWM Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Gate Driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
5
Outline Dimension . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Version 2.2
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4 Jul 2011
Quasi-Resonant PWM Controller
ICE2QS01
Pin Configuration and Functionality
1
Pin Configuration and Functionality
1.1
Pin Configuration
Pin
Symbol
Function
1
ZC
Zero Crossing
2
REG
Regulation
3
CS
Primary Current Sensing
4, 5
HV
High Voltage input
6
OUT
gate driver output
7
VCC
IC supply voltage
8
GND
Common ground
1.2
REG (Regulation)
Normally, an external capacitor is connected to this pin
for a smooth voltage Vreg. Internally, this pin is
connected to the PWM signal generator for switch-off
determination (together with the current sensing
signal), the digital signal processing for the frequency
reduction with decreasing load during normal
operation, and the burst mode controller for entering
burst mode operation determination and burst ratio
control during burst mode operation. Additionally, the
open-loop / over-load protection is implemented by
monitoring the voltage at this pin.
CS (Current Sensing)
This pin is connected to the shunt resistor for the
primary current sensing, externally, and the PWM
signal generator for switch-off determination (together
with the regulation voltage), internally. Moreover, shortwinding protection is realised by monitoring the voltage
Vcs during on-time of the main power switch.
Package PG-DIP-8
ZC
1
8
GND
REG
2
7
VCC
CS
3
6
OUT
HV
4
Figure 1
1.3
5
HV (High Voltage)
The pin HV is connected to the bus voltage, externally,
and to the power cell, internally. The current through
this pin pre-charges the VCC capacitor once the supply
bus voltage is applied. Additionally, the current through
this pin supplies the IC in case that the output voltage
is lowered during active burst mode operation, or
during latch-off mode.
OUT (Gate drive output)
This output signal drives the external main power
switch, which is a power MOSFET in most case.
HV
VCC (Power supply)
This is the IC power supply pin. Externally, this pin is
connected to the VCC capacitor, which is supplied by
the inside power cell during VCC charge-up, burst
mode operation at lowered output voltage or during
latched-off of the IC, and the auxiliary winding during
normal operation or burst mode operation with high
enough voltage across the auxiliary winding. Based on
this voltage, the VCC under- or over-voltage protection
are implemented.
Pin Configuration PG-DIP-8(top view)
Pin Functionality
ZC (Zero Crossing)
At this pin, the voltage from the auxiliary winding after
a time delay circuit is applied. Internally, this pin is
connected to the zero-crossing detector for switch-on
determination. Additionally, the output overvoltage
detection is realized by comparing the voltage Vzc with
an internal preset threshold.
Version 2.2
GND (Ground)
This is the common ground of the controller.
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4 Jul 2011
Quasi-Resonant PWM Controller
ICE2QS01
Representative block diagram
2
Representative block diagram
VZCT2
VZCT1
ZC
1
VOLP
OLP
VVCCOVP
VCC
OVP
Zero-crossing
counter
active burst
control
VCC
UVP
REG
2
RReg
up/down
counter
auto
restart
PWM generator
ringing
suppression
time control
Vvccuvp
VOPOVP
VREF
VcsSW
output
OVP
SWP
latch
off
on/off FF
gate driver
current limitation /
foldback correction
CS
3
OUT
6
Vcsth
power management
HV
4, 5
power cell
current measurement
v1
controller
GND
8
Vos
VCC
7
Figure 2
Version 2.2
Representative Blockdigram
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04 Jul 2011
Quasi-Resonant PWM Controller
ICE2QS01
Functional Description
3
Functional Description
3.1
VCC Pre-Charging and Typical
VCC Voltage During Start-up
drops (Phase II). Once the output voltage is high
enough, the VCC capacitor receives then energy from
the auxiliary winding from the time point t2 on. The VCC
then will reach a constant value depending on output
load.
Since there is a VCC undervoltage protection, the
capacitance of the VCC capacitor should be selected to
be high enough to ensure that enough energy is stored
in the VCC capacitor so that the VCC voltage will never
touch the VCC under voltage protection threshold
VVCCUVP before the output voltage is built up. Therefore,
the capacitance should fulfill the following requirement:
In the controller ICE2QS01, a power cell is integrated.
As shown in Figure 2, the power cell consists of a high
voltage device and a controller, whereby the high
voltage device is controlled by the controller. The
power cell provides a pre-charging of the VCC
capacitor till VCC voltage reaches the VCC turned-on
threshold VVCCon and the IC begins to operate, while it
may keep the VCC voltage at a constant value during
burst mode operation when the output voltage is pulled
down or the power from the auxiliary winding is not
enough, or when the IC is latched off in certain
protection mode.
Once the mains input voltage is applied, a rectified
voltage shows across the capacitor Cbus. The high
voltage device provides a current to charge the VCC
capacitor Cvcc. Before the VCC voltage reaches a
certain value, the amplitude of the current through the
high voltage device is only determined by its channel
resistance and can be as high as several mA. After the
VCC voltage is high enough, the controller controls the
high voltage device so that a constant current around
1mA is provided to charge the VCC capacitor further,
until the VCC voltage exceeds the turned-on threshold
VVCCon. As shown as the time phase I in Figure 3, the
VCC voltage increase near linearly.
I VCCop × ( t 2 – t 1 )
C vcc ³ ----------------------------------------------V VCCon – V VCCUVP
with IVCCop the operating current of the controller.
3.2
i
ii
3.3
iii
Figure 3
t2
t
VCC voltage at start up
The time taking for the VCC pre-charging can then be
approximately calculated as:
V VCCon × C vcc
t 1 = ---------------------------------I VCCch arg e2
[1]
where IVCCcharge2 is the charging current from the power
cell which is 1.05mA, typically.
Exceeds the VCC voltage the turned-on threshold
VVCCon of at time t1, the power cell is switched off, and
the IC begins to operate with a soft-start. Due to power
consumption of the IC and the fact that still no energy
from the auxiliary winding to charge the VCC capacitor
before the output voltage is built up, the VCC voltage
Version 2.2
Normal Operation
The PWM section of the IC can be divided into two
main portions: PWM controller for normal operation
and PWM controller for burst mode operation. The
PWM controller for normal operation will be described
in the following paragraphs, while the PWM controller
for burst mode operation will be discussed in the next
section.
The PWM controller for normal operation consists of
digital signal processing circuit including an up/down
counter, a zero-crossing counter (ZC-counter) and a
comparator, and analog circuit including a current
measurement unit and a comparator. The switch-on
and -off time point is determined by the digital circuit
and the analog circuit, respectively. As input
information for the switch-on determination, the zerocrossing input signal and the value of the up/down
counter are needed, while the feedback signal vREG
and the current sensing signal vCS are necessary for
the switch-off determination. Details about the
operation of the PWM controller in normal operation
are illustrated in the following paragraphs.
VVCCUVP
t1
Soft-start
At the time t1, the IC begins to operate with a soft-start.
By this soft-start the switching stresses for the switch,
diode and transformer are minimised. The soft-start
implemented in the ICE2QS01 is a digital time-based
function. The preset soft-start time is 24ms with 8
steps. The internal reference for the regulation voltage
begins at 1.35V and with an increment of 0.35V for
each following step.
VCC
VVCCon
[2]
3.3.1
Switch-on Determination
As mentioned above, the digital signal processing
circuit consists of an up/down counter, a zero-crossing
counter and a comparator. A ringing suppression time
7
4 Jul 2011
Quasi-Resonant PWM Controller
ICE2QS01
Functional Description
controller is implemented to avoid mistriggering by the
ring after MOSFET is turned off. Functionality of these
parts is described as in the following.
limited between 1 and 7. If the counter tends to count
beyond this range, the attempt is ignored.
In normal case, the up/down counter can only be
changed by one each time at the clock period of 48ms.
However, to ensure a fast response to sudden load
increase, the counter is set to 1 in the following
switching period after the regulation voltage vREG
exceeds the threshold VRM.
3.3.1.1
Up/down Counter
The up/down counter stores the number of zero
crossing to be ignored before the main power switch is
switched on after demagnetisation of the transformer.
This value is a function of the regulation voltage, which
contains information about the output power.
Generally, a high output power results in a high
regulation voltage. According to this information, the
value in the up/down counter is changed to a low value
in case of high regulation voltage, and to a high value
in case of low regulation voltage. In ICE2QS01, the
lowest value of the counter is 1 and the highest 7.
Following text explains how the up/down counter value
changes in responding to the regulation voltage vREG.
The regulation voltage vREG is internally compared with
three thresholds VRL, VRH and VRM. According to the
results, the value in the up/down counter is changed,
which is summarised in Table 1 and Figure 4
respectively.
Table 1
Operation of the up/down counter
up/down counter
vREG
action
Count upwards till
Always lower than VRL
7
Once higher than VRL, but
Stop counting, no
always lower than VRH
value changing
Once higher than VRH, but
Count downwards
always lower than VRM
till 1
Set up/down
Once higher than VRM
counter to 1
clock
3.3.1.2
Zero-Crossing Counter and Ringing
Suppression Time Controller
In the system, the voltage from the auxiliary winding is
applied to the zero-crossing pin through a RC network,
which provides a time delay to the voltage from the
auxiliary winding. Internally, this pin is connected to a
clamping network, a zero-crossing detector, an output
overvoltage (OP OVP) detector and a ringing
suppression time controller.
During on-state of the power switch a negative voltage
applies to the ZC pin. Through the internal clamping
network, the voltage at the pin is clamped to certain
level. However, it is highly recommended that a fastrecovery diode Dzc is added to block the negative
voltage when the power switch is on. This is because
the device in MOS technology is sensitive to negative
voltage.
The voltage at the ZC pin vZC is compared with the
threshold VZCT1. Once the voltage vZC crosses the
threshold at its falling edge, a pulse is generated which
is fed to the zero-crossing counter and the counter
value increases by 1.
After MOSFET is turned on, there will be some
oscillation on VDS, which will also appear on the voltage
on ZC pin. To avoid the MOSFET is turned on
mistriggerred by such oscillation, a ringing suppression
timer is implemented. The time is dependent on the
voltage vZC. When the voltage vZC is lower than the
threshold VZCT2, a longer preset time applies, while a
shorter time is set when the voltage vZC is higher than
the threshold.
The voltage vZC is used for the output overvoltage
protection, as well. Once the voltage at this pin is
higher than the threshold VOPOVP during off-time of the
main switch, the IC is latched off after a fixed blanking
time.
To achieve the switch-on at voltage valley, the voltage
from the auxiliary winding is fed to a time delay network
(the RC network consists of Dzc, Rzc1, Rzc2 and Czc as
shown in typical application circuit) before it is applied
to the zero-crossing detector through the ZC pin. The
needed time delay to the main oscillation signal Dt
should be approximately one fourth of the oscillation
period (by transformer primary inductor and drainsource capacitor) minus the propagation delay from the
T=48ms
t
V FB
V RM
V RH
V RL
n
n+1
n+2
n+2
n+2
n+2
n+1
n
n-1
t
1
Case 1
4
5
6
6
6
6
5
4
3
1
Case 2
2
3
4
4
4
4
3
2
1
1
Case 3
7
7
7
7
7
7
6
5
4
1
Figure 4
Up/down counter operation
According to the comparison results the up/down
counter counts upwards, keeps unchanged or counts
downwards. However, the value in up/down counter is
Version 2.2
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4 Jul 2011
Quasi-Resonant PWM Controller
ICE2QS01
Functional Description
3.3.2
Switch-off Determination
In the converter system, the primary current is sensed
by an external shunt resistor, which is connected
between low-side terminal of the main power switch
and the common ground. The sensed voltage across
the shunt resistor vCS is applied to an internal current
measurement unit, and its output voltage v1 is
compared with the regulation voltage vreg. Once the
voltage v1 exceeds the voltage vREG, the output flip-flop
is reset. As a result, the main power switch is switched
off. The relationship between the v1 and the vcs is
described by:
detected zero-crossing to the switch-on of the main
switch tdelay, theoretically:
T osc
Dt = ---------- – t delay
4
[3]
This time delay should be matched by adjusting the
time constant of the RC network which is calculated as:
R zc1 × R zc2
t td = C zc × --------------------------R zc1 + R zc2
[4]
3.3.1.3
Switch-on Determination
In the system, turn-on of the power switch depends on
the value of the up/down counter, the value of the zerocrossing counter and the voltage at the ZC pin vZC.
Turn-on happens only when the value in the both
counters are the same and the voltage at the ZC is
lower than the threshold VZCT1. For comparison of the
values from both counters, a digital comparator is used.
Once these counters have the same value, the
comparator generates a signal which sets the on/off
flip-flop, only when the voltage vZC is lower than the
threshold VZCT1.
Another signal which may trigger the digital comparator
is the output of a TsMax clock signal, which limits the
maximum off time to avoid the low-frequency
operation.
During active burst mode operation, the digital
comparator is disabled and no pulse will be generated.
v 1 = 3.3 × v CS + 0.7
[5]
To avoid mistriggering caused by the voltage spike
across the shunt resistor after switch-on of the main
power switch, a 330ns leading edge blanking time
applies to output of the comparator.
3.3.3
Foldback Point Correction
In addition to the cycle-by-cylce primary current
limitation, the IC incorporats a foldback point
correction. The current limit on CS pin voltage is now a
time dependent one. If the mains input voltage is high,
the MOSFET on time will be short and the current limit
will be low. In such a way, the maximum output power
for the SMPS designed with ICE2QS01 will be nearly
constant against the variations of mains input voltage.
The current sense voltage limit versus the MOSFET
maximum on time is shown in Figure 5.
1
Vcs-max(V)
0 .8
0 .6
0 .4
0 .2
0
0
5
10
15
20
25
30
Ton(us)
Figure 5 Maximum current limit versus MOSFET maximum on time
Version 2.2
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4 Jul 2011
Quasi-Resonant PWM Controller
ICE2QS01
Functional Description
3.4
Active Burst Mode Operation
exceed VLB (4.5V). After leaving active busrt mode,
maximum current can now be provided to stabilize VO.
In addition, the up/down counter will be set to 1
immediately after leaving active burst mode. This is
helpful to decrease the output voltage undershoot.
At very low load condition, the IC enters active burst
mode operation to minimize the input power. Details
about active burst mode operation are explained in the
following paragraphs.
3.4.4
IC Power Supply During Active Burst
Mode
During active burst mode operation, the power cell is
activated again. Once the power from the auxiliary
winding is not high enough to keep the VCC voltage
above the preset value of VVCCBL, the power cell keeps
the VCC voltage at the preset value VVCCBL. Otherwise,
if the VCC voltage is still above this value, no current
flows through the power cell though it is activated.
3.4.1
Entering Active Burst Mode Operation
For determination of entering active burst mode
operation, three conditions apply:
the regulation voltage is lower than the threshold of
VEB(1.1V). Accordingly, the peak voltage across the
shunt resistor is 0.11V;
the up/down counter has its maximal value of 7; and
a certain blanking time (24ms).
Once all of these conditions are fulfilled, the active
burst mode flip-flop is set and the controller enters
burst mode operation. This multi-conditional
determination for entering active burst mode operation
prevents mistriggering of entering active burst mode
operation, so that the controller enters active burst
mode operation only when the output power is really
low during the preset blanking time.
VREG
4.4V
3.6V
3.0V
Entering
Active Burst
Mode
Leaving
Active Burst
Mode
1.1V
Blanking Window (24ms)
3.4.2
During Active Burst Mode Operation
After entering the Active Burst Mode the regulation
voltage rises as VOUT starts to decrease due to the
inactive PWM section. One comparator observes the
regulation signal if the voltage level VBH (3.6V) is
exceeded. In that case the internal circuit is again
activated by the internal bias to start with swtiching.
Turn-on of the power MOSFET is triggered by the
timer. The PWM generator for burst mode operation
composes of a timer with a fixed frequency of 80kHz,
typically, and an analog comparator. Turn-off is
resulted by comparison of the voltage signal v1 with an
internal threshold, by which the voltage across the
shunt resistor VcsB is 0.25V, accordingly. A turn-off can
also be triggered by the maximal duty ratio controller
which sets the maximal duty ratio to 50%. In operation,
the output flip-flop will be reset by one of these signals
which come first.
If the output load is still low, the regulation signal
decreases as the PWM section is operating. When
regulation signal reaches the low threshold VBL(3.0V),
the internal bias is reset again and the PWM section is
disabled until next time regultaion siganl increases
beyond the VBH threshold. If working in active burst
mode the regulation signal is changing like a saw tooth
between 3.0V and 3.6V shown in Figure 6.
t
VCS
1.0V
Current limit level
during Active Burst
Mode
0.25V
VVCC
t
12.5V
VO
t
Max. Ripple < 1%
t
Figure 6 Signals in active burst mode
3.4.3
Leaving Active Burst Mode
The regulation voltage immediately increases if there is
a high load jump. This is observed by one comparator.
As the current limit is 25% during active burst mode a
certain load is needed so that regulation voltage can
Version 2.2
10
4 Jul 2011
Quasi-Resonant PWM Controller
ICE2QS01
Functional Description
3.5
Protection Functions
The IC provides full protection functions. The following
table summarizes these protection functions.
Table 2
Protection features
VCC Overvoltage
Auto Restart Mode
VCC Undervoltage
Auto Restart Mode
Overload/Open Loop
Auto Restart Mode
Output Overvoltage
Latched Off Mode
Short Winding
Latched Off Mode
During operation, the VCC voltage is continuously
monitored. In case of an under- or an over-voltage, the
IC is reset and the main power switch is then kept off.
After the VCC voltage falls below the threshold
VVCCUVP, the power cell is activated. The VCC capacitor
is then charged up. Once the voltage exceeds the
threshold VVCCon, the IC begins to operate with a new
soft-start.
In case of open control loop or output over load, the
regulation voltage will be pulled up . After a blanking
time of 24ms, the IC enters auto-restart mode. The
blanking time here enables the converter to provide a
high power in case the increase in VREG is due to a
sudden load increase. During off-time of the power
switch, the voltage at the zero-crossing pin is
monitored for output over-voltage detection. If the
voltage is higher than the preset threshold vOPOVP, the
IC is latched off after the preset blanking time.
If the voltage at the current sensing pin is higher than
the preset threshold vcsSW during on-time of the power
switch, the IC is latched off. This is short-winding
protection.
During latch-off protection mode, the power cell is
activated and it keeps the VCC voltage at the level of
VVCCBL.
Version 2.2
11
4 Jul 2011
Quasi-Resonant PWM Controller
ICE2QS01
Electrical Characteristics
4
Electrical Characteristics
Note:
All voltages are measured with respect to ground (Pin 8). The voltage levels are valid if other ratings are
not violated.
4.1
Note:
Absolute Maximum Ratings
Absolute maximum ratings are defined as ratings, which when being exceeded may lead to destruction
of the integrated circuit. For the same reason make sure, that any capacitor that will be connected to pin 7
(VCC) is discharged before assembling the application circuit.
Parameter
Symbol
Limit Values
min.
max.
Unit
Remarks
HV Voltage
VHV
-
500
V
VCC Supply Voltage
VVCC
-0.3
27
V
REG Voltage
VREG
-0.3
5.0
V
ZC Voltage
VZC
-0.3
5.0
V
CS Voltage
VCS
-0.3
5.0
V
OUT Voltage
VOUT
-0.3
27
V
Junction Temperature
Tj
-40
125
°C
Storage Temperature
TS
-55
150
°C
Thermal Resistance
Junction-Ambient
RthJA
-
90
K/W
PG-DIP-8
ESD Capability
VESD
-
2
kV
Human body model1)
1)
According to EIA/JESD22-A114-B (discharging a 100pF capacitor through a 1.5kW series resistor)
4.2
Note:
Operating Range
Within the operating range the IC operates as described in the functional description.
Parameter
Symbol
Limit Values
min.
Unit
max.
VCC Supply Voltage
VVCC
VVCCUVP VVCCOVP V
Junction Temperature
TjCon
-25
Version 2.2
12
Remarks
125
°C
4 Jul 2011
Quasi-Resonant PWM Controller
ICE2QS01
Electrical Characteristics
4.3
4.3.1
Note:
Characteristics
Supply Section
The electrical characteristics involve the spread of values guaranteed within the specified supply voltage
and junction temperature range TJ from – 25 oC to 125oC. Typical values represent the median values,
which are related to 25°C. If not otherwise stated, a supply voltage of VCC = 18 V is assumed.
Parameter
Symbol
Limit Values
min.
typ.
max.
Unit
Test Condition
Start-Up Current
IVCCstart
-
300
550
mA
VVCC = 21V
VCC Charge Current
IVCCcharge1
-
-
5.0
mA
VVCC = 0V
IVCCcharge2
0.55
1.05
1.60
mA
VVCC = 1V
IVCCcharge3
-
0.88
-
mA
VVCC = 21V
Leakage Current of
Power Cell
IStartLeak
-
0.2
50
mA
VHV= 610V
at Tj = 100°C
Supply Current in normal
operation
IVCCop
-
2.5
3.6
mA
Output low
Supply Current in
Auto Restart Mode
with Inactive Gate
IVCCrestart
-
300
-
mA
Supply Current in
Latch-off Mode
IVCClatch
-
300
-
mA
Supply Current in Burst Mode
with Inactive Gate
IVCCburst
-
500
950
mA
VREG = 2.5V
Supply Voltage with no power
from auxiliary winding in burst
mode or in latch-off mode
VVCCBL
-
12.5
-
V
VHV = 100V
VCC Turn-On Threshold
VVCCon
21.2
22.0
22.8
V
Internal Reference Voltage
VREF
4.8
5.0
5.2
V
Version 2.2
13
measured at pin REG,
IREG = 0
4 Jul 2011
Quasi-Resonant PWM Controller
ICE2QS01
Electrical Characteristics
4.3.2
PWM Section
Parameter
Symbol
Limit Values
min.
typ.
max.
Unit
Regulation Pull-Up Resistor
RREG
14
23
33
kW
PWM-OP Gain
AV
3.18
3.3
-
-
Offset for Voltage Ramp
VOS
0.63
0.7
-
V
Soft-Start time
tSOFTS
18
21
38
ms
Zero crossing threshold voltage VZCT1
20
50
110
mV
Ringing suppression threshold
VZCT2
Minimum ringing suppression
time
tZCRST1
2.2
4.2
5.5
ms
VZC > VZCT2
Maximum ringing suppression
time
tZCRST2
-
42
-
ms
VZC < VZCT2
Threshold to set Up/Down
Counter to one
VRM
-
3.9
-
V
Threshold for downward
counting
VRH
-
3.2
-
V
Threshold for upward counting
VRL
-
2.5
-
V
Counter time
tCOUNT
-
48
-
ms
Maximum restart time in normal
operation
tsMax
33
42
60
ms
Leading Edge Blanking
tLEB
200
330
460
ns
Peak current limitation in normal
operation
Vcsth
0.95
1.0
1.05
V
Regulation voltage for entering
Burst Mode
VEB
-
1.1
-
V
Regulation voltage for leaving
Burst Mode
VLB
-
4.5
-
V
Regulation voltage for burst-on
VBH
-
3.6
-
V
Regulation voltage for burst-off
VBL
-
3.0
-
V
Fixed Switching Frequency in
Burst Mode
fsB
64
80
96
kHz
Max. Duty Cycle in Burst Mode
DmaxB
-
0.5
-
Peak Current Limitation in Burst
Mode
VcsB
0.22
0.25
0.3
1)
0.7
Test Condition
V
VZC