ICE2QS02G [INFINEON]
Quasi-Resonant PWM Controller; 准谐振PWM控制器
| 型号： | ICE2QS02G |
| 厂家： | 
Infineon |
| 描述： | Quasi-Resonant PWM Controller |
| 文件： | 总17页 (文件大小：412K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
Datasheet Version 2.0, 13 June 2008
ICE2QS02G
Quasi-Resonant PWM
Controller
Power Management & Supply
N e v e r s t o p t h i n k i n g .
13 June 2008
Revision History:
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Datasheet
Previous Version:
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Subjects (major changes since last revision)
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Edition 13 June 2008
Published by
Infineon Technologies AG
81726 München, Germany
© Infineon Technologies AG 2006.
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ICE2QS02G
Quasi-Resonant PWM Controller
Product Highlights
•
•
•
•
•
Quasi-resonant operation for higher efficiency and better EMI
Digital frequency reduction for higher average efficiency
Optimized for applications with auxiliary converter
Various protection features with Latch Mode and Auto-restart Mode
Adjustable blanking time for Over Load Protection and adjustable
restart time
ICE2QS02G
PG-DSO-8
•
Pb-free lead plating; RoHS compliant
Features
Description
•
Quasi-resonant operation
ICE2QS02G is a second generation quasi-resonant
PWM controller optimized for off-line power supply
applications such as LCD TV, audio and printers, where
an auxiliary power supply for the IC is provided. 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 a free running quasi resonant converter implemented
with maximum switching frequency limitation only.
•
•
•
Load dependent digital frequency reduction
Built-in digital soft-start
Cycle-by-cycle peak current limitation with built-in
leading edge blanking time
•
•
VCC undervoltage protection
Mains undervoltage protection with adjustable
hysteresis
•
Foldback Point Correction with digitalized sensing
and control circuits
In addition, numerous protection functions have been
implemented in the IC to protect the system and
customize the IC for the chosen application. All of these
make the ICE2QS02G an outstanding product for real
quasi-resonant flyback converter in the market.
•
•
•
Over Load Protection with adjustable blanking time
Adjustable restart time after Over Load Protection
Adjustable output overvoltage protection with Latch
mode
•
•
•
Short-winding protection with Latch mode
Maximum on time limitation
Maximum switching period limitation
Typical Application
Mains
Lf
Input Voltage
Wp
Wa
DO
Snubber
Cf
VO
Cbus
RVINS1
Ws
RZC2
RZC1
CZC
CO
RVINS2
Auxiliary Supply
VINS VCC ZC
RBL
CBL
BL
CPS
Rb1
CDS
Vcc Power Management
Zero Crossing Detection
Gate
Driver
GATE
Rb2
Rovs1
GND
Global Protection Block
Optocoupler
Rc1
Digital Process Block
Current Mode Control
Current
CFB
FB
Limitation
CS
RCS
Cc2
Cc1
control unit
TL431
ICE2QS02G
Rovs2
Type
Package
ICE2QS02G
PG-DSO-8-8
Version 2.0
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Quasi-Resonant PWM Controller
ICE2QS02G
Table of Contents
Page
1
Pin Configuration and Functionality . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Pin Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Pin Functionality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
1.1
1.2
1.3
2
Representative Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
3
Functional Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Startup Phase. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
PWM Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Digital Frequency Reduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Up/down counter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Zero crossing (ZC counter). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Ring suppression time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Switch on determination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Switch Off Determination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Current Limitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Foldback Point Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Protection Functions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
3.1
3.2
3.3
3.3.1
3.3.1.1
3.3.1.2
3.3.1.3
3.3.1.4
3.3.2
3.4
3.4.1
3.5
4
Electrical Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Operating Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Supply Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Internal Voltage Reference. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
PWM Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Current Limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Soft Start. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Foldback Point Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Digital Zero Crossing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Gate Driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
4.1
4.2
4.3
4.3.1
4.3.2
4.3.3
4.3.4
4.3.5
4.3.6
4.3.7
4.3.8
4.3.9
5
Outline Dimension . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
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Pin Configuration and Functionality
1
Pin Configuration and Functionality
the transformer is detected when the ZC voltage falls
below VZCCT(100mV). Second, after the MOSFET is
turned off, an output overvoltage fault will be assumed
if VZC is higher than VZCOVP (4.5V). Finally, during the
MOSFET on time, a current depending on the main
input voltage flows out of this pin. Information on this
current is then used to adjust the maximum current
limit. More details on this function are provided in
Section 3.4.
1.1
Pin Configuration
Pin
Symbol
Function
1
2
3
4
5
6
7
8
BL
Blanking Time
ZC
Zero Crossing
FB
Feedback
CS
Primary Current Sensing
Input Voltage Sensing
Gate Driver Output
Controller Supply Voltage
Controller Ground
FB (Feedback)
VINS
GATE
VCC
GND
Usually, an external capacitor is connected to this pin
to smooth the feedback voltage. Internally, this pin is
connected to the PWM signal generator for switch-off
determination (together with the current sensing
signal), and to the digital signal processing for the
frequency reduction with decreasing load during
normal operation. Additionally, the openloop/overload
protection is implemented by monitoring the voltage at
this pin.
1.2
Package
CS (Current Sensing)
BL
ZC
FB
CS
1
2
3
4
8
7
6
5
GND
VCC
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 feedback voltage), internally. Moreover, short-
winding protection is realised by monitoring the Vcs
voltage during on-time of the main power switch.
GATE
VINS
VINS (Input Voltage Sensing)
The voltage at this pin is used for Mains Undervoltage
Protection. The protection is triggered, once VVINS
drops below 1.25V. For a stable operation, a hysteresis
operation is ensured using an internal current source
(See Section 3.5). When the VVINS exceeds the
hysteresis point, the system resumes its operation with
a soft-start.
Figure 1
Pin configuration PG-DSO-8-8 (top view)
Gate(Gate drive output)
The GATE pin is the output of the internal driver stage,
which has a rise time of 100ns and a fall time of 25ns
when driving a 2.2nF capacitive load.
1.3
Pin Functionality
BL (Adjustable Blanking Time)
By connecting a capacitor and a resistor in parallel
between this pin and the ground, the blanking time for
can be fully adjusted, as well as the restart time. This
allows the system to face a sudden power surge for a
short period of time without triggering the overload
protection. Once the protection triggered, the IC will
restart using the internal soft-start circuit, after a period
of time fixed by the external resistance and capacitor.
VCC (Power supply)
The VCC pin is the positive supply of the IC and should
be connected to an external auxiliary supply.
GND (Ground)
This is the common ground of the controller.
ZC (Zero Crossing)
Three functions are incorporated at the ZC pin. First,
during MOSFET off time, the full demagnetization of
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ICE2QS02G
Representative Block Diagram
2
Representative Block Diagram
Figure 2
Representative block diagram
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ICE2QS02G
Funtional Description
switch-on and switch-off time points are each
determined by the digital circuit and the analog circuit,
respectively. As input information for the switch-on
determination, the zero-crossing input signal and the
value of the up/down counter are needed, while the
feedback signal VFB and the current sensing signal VCS
are necessary for the switch-off determination. Details
about the full operation of the PWM controller in normal
operation are illustrated in the following paragraphs.
3
Funtional Description
All values which are used in the functional description
are typical values. For calculating the worst cases the
min/max values which can be found in section 4
Electrical Characteristics have to be considered.
3.1
General
ICE2QS02G is a second generation quasi-resonant
controller IC developed by Infineon Technologies. Its
application is mainly focused on power systems with
external standby power control, such as in LCD TV or
printer applications. Hence, the required IC VCC
voltage for the IC is here drawn from an auxiliary power
supply.
The digital frequency reduction system implemented in
this IC allows highly efficient power converter
throughout all the load range. This IC possesses also
numerous adjustable protection features, in order to
protect the system and customize the IC for the target
applications.
3.3.1
Digital Frequency Reduction
As mentioned above, the digital signal processing
circuit consists of an up/down counter, a ZC counter
and a comparator. These three parts are key to
implement digital frequency reduction with decreasing
load. In addition, a ringing suppression time controller
is implemented to avoid mistriggering by the high
frequency oscillation, when the output voltage is very
low under conditions such as soft start or output short
circuit . Functionality of these parts is described as in
the following.
3.3.1.1
Up/down counter
The up/down counter stores the number of the zero
crossing to be ignored before the main power switch is
switched on after demagnetisation of the transformer.
This value is fixed according to the feedback voltage,
VFB, which contains information about the output
power. Indeed, in a typical peak current mode control,
a high output power results in a high feedback voltage,
and a low output power leads to a low regulation
voltage. Hence, according to VFB, the value in the up/
down counter is changed to vary the power MOSFET
off-time according to the output power. In the following,
the variation of the up/down counter value according to
the feedback voltage is explained.
3.2
Startup Phase
At the time ton, 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 ICE2QS02G is a digital time-
based function. The preset soft-start time is 16ms with
4 steps. The internal reference for the feedback voltage
begins at 1.8V and with an increment of 0.55V for each
following step. During soft start, the Over Load
Protection function is disabled.
Vsst (V)
4.00
The feedback voltage VFB is internally compared with
three threshold voltages VFBZL, VFBZR1 and VFBZH, at
each clock period of 48ms. The up/down counter
counts then upward, keep unchanged or count
downward, as shown in Table 1.
3.45
2.9
2.35
1.8
Table 1
Operation of the up/down counter
up/down counter
action
vFB
ton
4
8
12
16
Time(ms)
Count upwards till
Always lower than VFBZL
7
Figure 3
Soft-start control voltage versus time
Once higher than VFBZL, but
always lower than VFBZH
Stop counting, no
value changing
3.3
PWM Control
Once higher than VFBZH, but Count downwards
The PWM controller during normal operation consists
of a digital signal processing circuit including an up/
down counter, a zero-crossing counter (ZC counter)
and a comparator, and an analog circuit including a
current measurement unit and a comparator. The
always lower than VFBZR1
till 1
Set up/down
counter to 1
Once higher than VFBZR1
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Funtional Description
In the ICE2QS02G, the number of zero crossing is to 0 every time after the GATE output is changed to
limited to 7. Therefore, the counter varies between 1 high.
and 7, and any attempt beyond this range is ignored.
When VFB exceeds VFBZR1 voltage, the up/down
counter is initialised to 1, in order to allow the system to
react rapidly to a sudden load increase. The up/down
counter value is also intialised to 1 at the start-up, to
ensure an efficient maximum load start up. Figure 4
shows some examples on how up/down counter is
changed according to the feedback voltage over time.
The use of two different thresholds VRL and VRH to
count upward or downward is to prevent frequency
jittereing when the feedback voltage is close to the
threshold point. However, for a stable operation, these
two thresholds must not be affected by the foldback
current limitation (see Section 3.4.1), which limits the
VCS voltage. Hence, to prevent such situation, the
threshold voltages, VFBZL and VFBZH, are changed
internally depending on the line voltage levels.
The voltage vZC is also used for the output overvoltage
protection. Once the voltage at this pin is higher than
the threshold VZCOVP (4.5V) during off-time of the main
switch, the IC is latched off after a fixed blanking time
(tZCOVP).
To achieve the switch-on at minimum value of drain-
source voltage, the voltage from the auxiliary winding is
fed to a time delay network (the RC network consists of
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 ∆t should be approximately one fourth
of the oscillation period (by transformer primary
inductor and drain-source capacitor) minus the
propagation delay from thedetected zero-crossing to
the switch-on of the main switch tdelay, theoretically:
T
osc
∆t = ------------ – t
[1]
clock
T=48ms
delay
4
This time delay should be matched by adjusting the
time constant of the RC network which is calculated as:
t
t
R
R
VFB
VFBZR1
VFBZH
VFBZL
zc1 zc2
--------------------------------
τ
= C
[2]
td
zc
R
+ R
zc1
zc2
3.3.1.3
Ringing suppression time
Up/down
counter
After MOSFET is turned on, there will be some
oscillation on VDS, which will also appear on the voltage
on ZC pin. To avoid that the MOSFET is turned on
1
1
1
1
Case 1
4
2
7
5
3
7
6
4
7
6
4
7
6
6
4
7
5
4
2
5
3
1
4
mistriggerred by such oscillations,
a
ringing
suppression timer is implemented. The time is
dependent on the voltage vZC. When the voltage vZC is
lower than the threshold VZCRS, a longer preset time
applies, while a shorter time is set when the voltage vZC
is higher than the threshold.
Case 2
Case 3
4
7
3
6
Figure 4 Up/down counter operation
3.3.1.2 Zero crossing (ZC counter)
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 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 around -
0.2V.
The ZC counter has a minimum value of 0 and
maximum value of 7. After MOSFET is turned off, every
time when the falling voltage ramp of on ZC pin crosses
the VZCCT (100mV) threshold, a zero crossing is
detected and ZC counter will increase by 1. It is reset
3.3.1.4
Switch on determination
After the gate drive goes to low, it can not be changed
to high during ring suppression time.
After ring suppression time, the gate drive can be
turned on when the ZC counter value is higher or equal
to up/down counter value.
However, it is also possible that the oscillation between
primary inductor and drain-source capacitor attenuates
very fast and IC can not detect enough zero crossings
and ZC counter value will not be high enough to turn on
the gate drive. In this case, a maximum switching
period (TPerMax) is implemented. After the specified
period since last time Gate is turned on, the gate drive
will be turned on again regardless of the counter values
and VZC. This function can effectively prevent the
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Quasi-Resonant PWM Controller
ICE2QS02G
Funtional Description
switching frequency from going lower than 20kHz, constant maximum input power of the converter, the
otherwise which will cause audible noise in most cases.
required maximum VCS versus various input bus
voltage can be calculated, which is shown in Figure 5.
3.3.2
Switch Off Determination
1
0.9
0.8
0.7
0.6
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 VFB. Once the
voltage V1 exceeds the voltage VFB, 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:
80 100 120 140 160 180 200 220 240 260 280 300 320 340 360 380 400
Vin(V)
V
= 3.3 VCS + 0.7
[3]
1
Figure 5 Variation of the VCS limit voltage according
to the IZC current
In addition, there is a maximum on time, tOnMax
,
limitation implemented in the IC. Once the gate drive
has been in high state longer than the maximum on
time, it will be turned off to prevent the switching
frequency from going too low because of long on time.
According to the typical application circuit, when
MOSFET is turned on, a negative voltage proportional
to bus voltage will be coupled to auxiliary winding.
Inside ICE2QS02G, an internal circuit will clamp the
voltage on ZC pin to nearly 0V. As a result, the current
flowing out from ZC pin can be calculated as
3.4
Current Limitation
There is a cycle by cycle current limitation realized by
the current limit comparator to provide an overcurrent
detection. The source current of the MOSFET is
sensed via a sense resistor RCS. By means of RCS the
source current is transformed to a sense voltage VCS
which is fed into the pin CS. If the voltage VCS exceeds
an internal voltage limit, adjusted according to the
Mains voltage, the comparator immediately turns off
the gate drive.
To prevent the Current Limitation process from
distortions caused by leading edge spikes, a Leading
Edge Blanking time (tLEB) is integrated in the current
sensing path.
A further comparator is implemented to detect
dangerous current levels (VCSSW) which could occur if
one or more transformer windings are shorted or if the
secondary diode is shorted. To avoid an accidental
latch off, a spike blanking time of tCSSW is integrated in
the output path of the comparator .
V
N
BUS
a
I
= ------------------------
[4]
ZC
R
N
ZC1
P
When this current is higher than IZC_1, the amount of
current exceeding this threshold is used to generate an
offset to decrease the maximum limit on VCS. Since the
ideal curve shown in Figure 5 is a nonlinear one, a
digital block in ICE2QS02G is implemented to get a
better control of maximum output power. Additional
advantage to use digital circuit is the production
tolerance is smaller compared to analog solutions. The
typical maximum limit on VCS versus the ZC current is
shown in Figure 6.
1
0.9
0.8
0.7
0.6
3.4.1
Foldback Point Correction
When the main bus voltage increases, the switch on
time becomes shorter and therefore the operating
frequency is also increased. As a result, for a constant
primary current limit, the maximum possible output
power is increased, which the converter may have not
been designed to support.
300
500
700
900
1100
1300
1500
1700
1900
2100
Izc(uA)
Figure 6
VCS-max versus IZC
To avoid such a situation, the internal foldback point
correction circuit varies the VCS voltage limit according
to the bus voltage. This means the VCS will be
decreased when the bus voltage increases. To keep a
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Quasi-Resonant PWM Controller
ICE2QS02G
Funtional Description
The blanking time for Over Load Protection can be
calculated using equation [5].
3.5
Protection Functions
ICE2QS02G provides various protection functions. The
VBLH
IBL
following table summarizes these protection functions.
TOLP = –RBLCBL ln 1 – -----------------
[5]
BL
R
Table 2
Protection features
The restart time for Over Load Protection can be
calculated using equation [6].
VCC Undervoltage
Latch off
Overload/Openloop
Protection
Auto restart
VBLL
V
TRESTART = –RBLCBL ln -------------
[6]
BLH
Main undervoltage
Protection
Block Gate
During the switch off time, the voltage at the zero-
crossing pin, ZC, is monitored for output overvoltage
detection. If this voltage is higher than the preset
threshold VZCOVP, the IC enters latch-off mode.
If the voltage at the current sensing pin is higher than
the preset threshold VCSSW of 1.68V during the on-time
of the power switch, the IC is latched off. This
consitutes a short winding protection.
Finally, this IC has an adjustable main undervoltage
detection system. Given the resistances RVINS1 and
RVINS2 connected to the VINS pin, the main turn off
voltage is given by equation [7].
recover with soft start
Output Overvoltage
Short Winding
Latch off
Latch off
During normal operation, the VCC voltage is
continuously monitored. In case of
a
VCC
undervoltage, the IC is reset and the main power switch
is kept off.
The Overload and Open Loop Protection contains an
adjustable blanking time and variable restart time.
Such an adjustable buffer time is indeed, useful, for
applications that usually work in low output power, but
RVINS1 + RVINS2
VBUSOFF = VVINSTH -----------------------------------------
[7]
require
a
short
duration
of
high
output
RVINS2
poweroccasionally. Here, when the regulation voltage,
VFB exceeds the threshold voltage of VFBOLP, an
internal current source of IBL starts charging the
external capacitor CBL. This current source turns off
only when the capacitor voltage, VBL reaches VBLH or
when VFB decreases below VFBH. Once VBL exceeds
For system stability, a hysteresis is implemented in the
main undervoltage protection using an internal current
source IVINS, so that the main turn on voltage is given
by equation [8].
V
BLH, the overload/openloop protection is triggered by
VBUSON = VBUSOFF + IVINSHys RVINS1
[8]
turning off the GATE signal, and pulling high the
feedback voltage. From this time, CBL slowly
discharges through the external resistance RBL. When
VBL drops below VBLL, the IC restarts its operation
beginning with soft-start. The charging time and the
discharging time of the capacitor CBL, fix respectively
the openloop/overload protection blanking time and the
restart time of the IC. One example about how this
protection works is shown in Figure 7.
Everytime IC recovers from a mains undervoltage
protection, IC will begin with a soft start.
VGATE
t
VBL
3.9V
0.5V
t
VFB
4.5V
t
trestart
trestart
tss
tss
tOLP
tOLP
Figure 7
Over Load Protection and timers
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Quasi-Resonant PWM Controller
ICE2QS02G
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
Absolute Maximum Ratings
Note: 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
Unit
Remarks
min.
max.
27
VCC Supply Voltage
VINS Voltage
VVCC
VVINS
VBL
-0.3
-0.3
-0.3
-0.3
-0.3
-0.3
-0.3
-40
V
5.0
V
BL Voltage
5.0
V
FB Voltage
VFB
5.0
V
ZC Voltage
VZC
5.0
V
CS Voltage
VCS
5.0
V
GATE Voltage
Junction Temperature
Storage Temperature
VGATE
Tj
10.0
125
150
185
V
°C
°C
K/W
TS
-55
Thermal Resistance
Junction-Ambient
RthJA(DSO)
PG-DSO-8
-
ESD Capability
VESD
-
2
kV
Human body model1)
1)
According to EIA/JESD22-A114-B (discharging a 100pF capacitor through a 1.5kΩ series resistor)
4.2
Operating Range
Note: Within the operating range the IC operates as described in the functional description.
Parameter
Symbol
Limit Values
min. max.
VVCCUVP 25
-25 125
Unit
Remarks
VCC Supply Voltage
Junction Temperature
VVCC
TjCon
V
°C
Version 2.0
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Quasi-Resonant PWM Controller
ICE2QS02G
Electrical Characteristics
4.3
Characteristics
4.3.1
Supply Section
Note: 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
Unit
Test Condition
min.
typ.
300
1.5
max.
Start-Up Current
IVCCstart
IVCCop
-
-
-
-
µA
VVCC = 11V
Output low
Supply Current in normal
operation
mA
I
FB = 0
Supply Current during Latch-off IVCCLO
-
300
-
µA
IFB = 0
mode
VCC Turn-On Threshold
VCC Turn-Off Threshold
VCC Turn-On/Off Hysteresis
VVCCon
VVCCoff
VVCChys
11.3
-
12.0
11.0
1
12.7
-
V
V
V
0.6
1.4
4.3.2
Internal Voltage Reference
Symbol
Parameter
Limit Values
Unit
Test Condition
min.
typ.
max.
5.10
Internal Reference Voltage
VREF
4.90
5.00
V
Measured at pin FB
IFB=0
Version 2.0
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Quasi-Resonant PWM Controller
ICE2QS02G
Electrical Characteristics
4.3.3
PWM Section
Parameter
Symbol
Limit Values
Unit
kΩ
V
Test Condition
min.
13
typ.
20
max.
Regulation Pull-Up Resistor
PWM-OP Gain
RFB
30
GPWM
VPWM
3.15
0.6
3.3
0.7
3.47
0.85
Offset for Voltage Ramp
4.3.4
Current Limit
Parameter
Symbol
Limit Values
Unit
Test Condition
Test Condition
min.
typ.
max.
Peak cuurent limitation in
normal operation
VCSTH
0.94
1.02
1.10
V
Leading Edge Blanking
tLEB
180
280
450
ns
4.3.5
Soft Start
Parameter
Symbol
Limit Values
Unit
min.
typ.
16
4
max.
Soft-Start time
soft-start time step 1)
tSS
11.8
-
ms
ms
V
tSSS
VSS1
Internal regulation voltage at
-
-
1.8
-
-
first step 1)
Internal regulation voltage step VSSS
at soft start 1)
0.55
V
4.3.6
Foldback Point Correction
Symbol
Parameter
Limit Values
Unit
Test Condition
min.
typ.
1.02
0.65
max.
FBC start point
VCS_FBC_S
-
-
-
-
V
V
IZC=0.5mA
IZC=1.8mA
CS threshold minimum
VCS_FBC_MIN
Version 2.0
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Quasi-Resonant PWM Controller
ICE2QS02G
Electrical Characteristics
4.3.7
Digital Zero Crossing
Symbol
Parameter
Limit Values
Unit
Test Condition
min.
50
typ.
100
-
max.
Zero crossing threshold voltage VZCCT
170
-
mV
mA
Maximum current out from zero IZCMAX
2.5
crossing pin1)
Threshold to set Up/Down
Counter to one
VFBZR1
VFBZHL
3.78
3.10
2.38
2.55
2.18
-
3.9
3.2
2.5
2.7
2.3
1.3
0.8
48
4
V
Threshold for downward
counting at low line
3.32
2.62
2.90
2.42
-
V
Threshold for upward counting VFBZLL
at low line
V
Threshold for downward
counting at high line
VFBZHH
V
Threshold for upward counting VFBZLH
at highline
V
ZC current for IC switches
threshold to high line
IZCHL
mA
mA
ms
ZC current for IC switches
threshold to low line
Counter time1)
IZCLL
-
-
tCOUNT
1)
The parameter is not subjected to production test - verified by design/characterization
4.3.8
Parameter
Protection
Symbol
Limit Values
Unit
Test Condition
min.
typ.
max.
Overload or Open Loop
Detection threshold for OLP
protection at FB pin
VFBOLP
4.4
4.5
4.6
V
Charging current at BL pin
IBL
12
20
28
µA
Threshold for adjustable
overload blanking time
VBLH
3.80
3.9
4.01
V
Threshold for adjustable restart VBLL
time
0.4
4.4
-
0.5
0.6
4.6
-
V
Output Overvoltage Detection
threshold at the ZC pin
VZCOVP
tZCOVP
VCSSW
4.5
V
Blanking time for output
100
1.68
190
µs
V
overvoltage protection1)
Threshold for short winding
protection
1.63
-
1.78
-
Blanking time for short winding tCSSW
protection
ns
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Quasi-Resonant PWM Controller
ICE2QS02G
Electrical Characteristics
Main Undervoltage Protection
threshold
VVINSTH
IVINSHys
tZCRS1
-
1.25
15
-
V
Main Undervoltage Protection
hysteresis current source
8.8
1.87
18
20
3.5
32
µA
µs
µs
Minimum ringing suppression
time
2.8
25
VZC > VZCT2
VZC < VZCT2
Maximum ringing suppression
time
tZCRS2
Ringing suppression threshold VZCRS
-
0.7
-
V
Maximum gate on time
tOnMax
tPerMax
25
42
30.0
50.0
35.1
57
µs
µs
VFB>4.3V, VCS=0
Maximum switching period
1)
The parameter is not subjected to production test - verified by design/characterization
4.3.9
Parameter
Gate Driver
Symbol
Limit Values
Unit
Test Condition
min.
typ.
max.
Output voltage at logic low
Output voltage at logic high
VGATElow
VGATEhigh
-
-
1.0
V
V
IOUT = 20mA;
VVCC=18V
9.0
10.0
-
-
IOUT = -20mA;
VCC=18V
V
Output voltage active shut down VGATEasd
-
-
-
1.0
V
V
VVCC = 7V
OUT = 20mA
I
Rise Time
Fall Time
trise
tfall
70
30
-
-
ns
COUT = 2.2nF; VGATE 2V
... 8V
ns
COUT = 2.2nF; VGATE 8V
... 2V
Version 2.0
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Quasi-Resonant PWM Controller
ICE2QS02G
Outline Dimension
5
Outline Dimension
PG-DSO-8
( Plastic Dual Small Outline)
Figure 8
PG-DSO-8-8
*Dimensions in mm
Version 2.0
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13 June 2008
Total Quality Management
Qualität hat für uns eine umfassende
Bedeutung. Wir wollen allen Ihren
Ansprüchen in der bestmöglichen
Weise gerecht werden. Es geht uns also
nicht nur um die Produktqualität –
unsere Anstrengungen gelten
gleichermaßen der Lieferqualität und
Logistik, dem Service und Support
sowie allen sonstigen Beratungs- und
Betreuungsleistungen.
Quality takes on an allencompassing
significance at Semiconductor Group.
For us it means living up to each and
every one of your demands in the best
possible way. So we are not only
concerned with product quality. We
direct our efforts equally at quality of
supply and logistics, service and
support, as well as all the other ways in
which we advise and attend to you.
Dazu gehört eine bestimmte
Part of this is the very special attitude of
our staff. Total Quality in thought and
deed, towards co-workers, suppliers
and you, our customer. Our guideline is
“do everything with zero defects”, in an
open manner that is demonstrated
beyond your immediate workplace, and
to constantly improve.
Throughout the corporation we also
think in terms of Time Optimized
Processes (top), greater speed on our
part to give you that decisive
competitive edge.
Geisteshaltung unserer Mitarbeiter.
Total Quality im Denken und Handeln
gegenüber Kollegen, Lieferanten und
Ihnen, unserem Kunden. Unsere
Leitlinie ist jede Aufgabe mit „Null
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Sichtweise auch über den eigenen
Arbeitsplatz hinaus – und uns ständig
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Unternehmensweit orientieren wir uns
dabei auch an „top“ (Time Optimized
Processes), um Ihnen durch größere
Schnelligkeit den entscheidenden
Wettbewerbsvorsprung zu verschaffen.
Geben Sie uns die Chance, hohe
Leistung durch umfassende Qualität zu
beweisen.
Give us the chance to prove the best of
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– you will be convinced.
Wir werden Sie überzeugen.
h t t p : / / w w w . i n f i n e o n . c o m
Published by Infineon Technologies AG
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