Infineon SMPS Seminar

SMPS Seminar SZ2006-08

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New CCM PFC Controller with BiCMOStechnology: ICE2PCS01

Infineon SMPS Seminar

25 Aug, 2006 - Shenzhen


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Features of CCM-PFC-IC ICE2PCS01 --- functional pin to pin compatible with ICE1PCS01

• Continuous conduction mode (CCM) Power

Factor Correction IC

• Low pin count (DIP- / SO-8)

• Simple Design

• Average current control without direct sinwave

reference signal sensing

• Numerous protection functions

• Designed for boost topology

• Stable output voltage during no-load operation

• Adjustable operating frequency (50kHz - 250kHz

for ICE2PCS01,ICE2PCS02 67kHz Fixed)

• Enhanced dynamic response

• Fulfills class D requirements of IEC 1000-3-2

• Continuous conduction mode (CCM) Power

Factor Correction IC

• Low pin count (DIP- / SO-8)

• Simple Design

• Average current control without direct sinwave

reference signal sensing

• Numerous protection functions

• Designed for boost topology

• Stable output voltage during no-load operation

• Adjustable operating frequency (50kHz - 250kHz

for ICE2PCS01,ICE2PCS02 67kHz Fixed)

• Enhanced dynamic response

• Fulfills class D requirements of IEC 1000-3-2

V, IOUT

IN

IL

IIN


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Application Circuit of CCM PFC Controller ICE2PCS01

L1

T1

R1

R2

COUT

RSense

VOUT = 400V DC

VIN = 85V ...265V AC

EMI Filter

R3

GATE GND VSENSEISENSE

C1 RFREQC2

R4

C3

VCOMPFREQICOMP

VCCAuxiliary Supply ICE2PCS01

Rectifier


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Parameters comparison between ICE1PCS01 and ICE2PCS01

Typ. 11.0VTyp. 10.2VVCC Turn-Off ThresholdTyp. 12.0VTyp. 11.2VVCC Turn-On Threshold11～26V10～21VVcc operating range3V±2％5V±2％Internal reference voltageBiCMOSBipolarDevice technology

ICE2PCS01ICE1PCS01Parameters


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Comparison between ICE1PCS01 and ICE2PCS01

faster soft start30uA current source charge Vcomp capacitor

10uA current source charge Vcomp capacitorSoft start

average current modeaverage current modeoperation mode

yes, typical threshold |Visense|=1.08V

yes, typical threshold |Visense|=1.08Vpeak current limit

yes, typical threshold |Visense|>=0.73V

yes, typical threshold |Visense|>=0.73Vsoft overcurrent control

yes, threshold is Vsense<0.6Vyes, threshold is Vsense<0.8Vopen loop protection

this function is not much useful.No.

PFC is shutdown when Vout<50% and restart immediately

output undervoltageprotection

yes, thresholds are +/-5%yes, thresholds are +/-5%enhance dynamic response

much fast and reliable

directly shutdown gate drive

reduce internal PWM control voltage via enhance dynamic response +5% threshold

Output overvoltageprotection

no audible noiseNo jitteringJittering due to grounding noiseOperating frequency

Advantages of ICE2PCS01ICE2PCS01ICE1PCS01Features


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General control stage block with feedforward

Small bandwidth voltage control loop, high bandwidth current control loop

The multiplier is the key element of the scheme

Feedforward technique compensates input voltage variations


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ICE2PCS01--- Average Current Control how to regulate current without sinewave reference signal sensing

In CCM mode boost converter, DOFF is proportional to VIN. In CCM mode boost converter, DOFF is proportional to VIN.

OUT

INOFF V

VD =

Average current control: regulate the IIN which is proportional to DOFF. The ramp voltage is generated by oscillator and the amplitude is controlled by VCOMP voltage.

Average current control: regulate the IIN which is proportional to DOFF. The ramp voltage is generated by oscillator and the amplitude is controlled by VCOMP voltage.

INOFFIN VDI ∝∝


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Normal operation (full load 300W)

Input Current

Input Voltage

Input Current

Input Voltage


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Start up – soft start behavior

ICE2PCS01:

• VCOMP is charged by a constant 30µA during startup.

• VCOMP rises linearly and so does the amplitude of the input current.

• The soft start is finished when the output voltage VOUT reaches 85% of its rated level.

• In normal operation, the IC operates with a higher maximum current at OTA1 and therefore with a higher voltage loop gain in order to improve the dynamic behavior of the device.

ICE2PCS01:

• VCOMP is charged by a constant 30µA during startup.

• VCOMP rises linearly and so does the amplitude of the input current.

• The soft start is finished when the output voltage VOUT reaches 85% of its rated level.

• In normal operation, the IC operates with a higher maximum current at OTA1 and therefore with a higher voltage loop gain in order to improve the dynamic behavior of the device.


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Startup at 85VAC --- soft start

No load

VoutIin

Vcomp

Vcc

Full load

Vbulk rising time is around 70ms when reaching 300VDC.


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No Frequency Jitter after startup


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Icomp pin short to GND test- worst case (265VAC, Iout=0A, AC on-off-on)

Vout

Vsense

VgateVgate is switched-off when Vsensereached 3.25V. Voutovershoot is around 430VDC


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Enhance Dynamic response

• Inherent PFC dynamic loop compensation is always implemented with low bandwidth in order not to make the response for 2*fL ripple.

• In case of load jump, regulation circuit can not response fast enough and it will lead to large output voltage overshoot or drop.

• Enhance dynamic response: Whenever output voltage exceeds by ±5%, it will act on the nonlinear gain block to affect the duty cycle directly.

• Inherent PFC dynamic loop compensation is always implemented with low bandwidth in order not to make the response for 2*fL ripple.

• In case of load jump, regulation circuit can not response fast enough and it will lead to large output voltage overshoot or drop.

• Enhance dynamic response: Whenever output voltage exceeds by ±5%, it will act on the nonlinear gain block to affect the duty cycle directly. VDC

VSENSE

Nonlinear gain

-5% +5%


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Enhance dynamic response(85VAC, Iout drop from 0.75A to 0A)

Vout

Iout

Vgate

Vsense

The gate was turned off when Vsensevoltage reached its threshold


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cont’Enhance dynamic response(85VAC, Iout jump from 0A to 0.75A)

Vout

Iout

Vgate

Vsense

Vsense drops to 2,85V, then Gate Duty increases rapidly


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Open Loop Protection

Protection Logic

VSENSEWhenever VSENSE voltage falls below 0.6V, or equivalently VOUT falls below 20% of its rated value, it indicates an open loop condition (i.e. VSENSE pin not connected) or an insufficient input voltage VIN for normal operation. In this case, most of the blocks within the IC will be shutdown.

Whenever VSENSE voltage falls below 0.6V, or equivalently VOUT falls below 20% of its rated value, it indicates an open loop condition (i.e. VSENSE pin not connected) or an insufficient input voltage VIN for normal operation. In this case, most of the blocks within the IC will be shutdown.

0.6V

VoutIin

Vgate

VsenseMax O/P Voltage is 420V


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Soft Over Current Control (55VAC, Iout=1.5A)

Vsense

Iin

The current was limited around 4A


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Peak Current limit (line jump from 85 to 265VAC, 300W)

Vin

VIsense

Iin


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Harmonic Analysis (85VAC)

Full load300W

Light load28W


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Harmonic Analysis (265VAC)

Full load300W

Light load28W


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Test Data and Plot

00.10.20.30.40.50.60.70.80.9

1

0 50 100 150 200 250 300 350

Pout (W)

PF

85

110

220

265

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Infineon SMPS Seminar