©2010. Renesas Electronics Corporation, All rights reserved.
Renesas Electronics URL http://www.renesas.com/pfcic
R2A20113
Conventional
Conventional
R2A20113
Critical conduction mode
Continue conduction mode
Previous
R2A20113
Features
Best support for power supplies of 1-phase operating
products that require low noise and downsizing
due to the power factor regulation for flat-screen TV, HDD recorder and AV home electronics.
4. Feedback Loop Detector
Feedback loop absence detect function can stop output
pulse. Therefore Renesas PFC IC prevents the breakings
of bulk capacitor and MOSFET.
FB
PFC out voltage
FB
PFC out voltage
In case of feedback
loop down, bulk
voltage is going up
abnormal voltage.
Then capacitor is
broken.
Detect the feedback loop
disconnection, and stop
the pulse!!
Prevent from the breakings of
Bulk capacitor & Power MOS!!!
cut
Error AMP
VREF
R2
R1
VOUT
VEO
Error AMP
FB
VREF
R2
R1
VOUT
In case of adopting gmAMP adopted, there is no
feedback current flow, and load regulation becomes good.
2. Improvement of Load Reg. Adopting gmAMP
FET current
Drain voltage
In CCM case, switching loss and radiation noise are large.
In CRM case, switching loss and radiation noise are small
due to zero current and zero voltage switching.
Recovery Loss of
Boost diode by ZCS
Basically,
no recovery diode
loss by zero current
switching too.
1. ZCD Line Less
5. Principle Power Loss Reduction
200ms/div
20ms/div
COMP
ILm
Vout
The R2A20113 has “Dynamic” and “Static” OVP.
Dynamic OVP is doing discharge error AMP voltage
before reaching Static OVP voltage. Therefore peak
current is limited. As the result, reduce over voltage
cause “No coil vibration”.
Simple External Circuit
Best for Small Power Supplies
• AC sense line less
• ZCD line less
No open/short detector, No turn-on at inrush
• Feedback loop detection
• High efficiency by Zero current switching
• Low radiation noise
• Small package: SOP8/DIP8
Specification
CS
Getting ZCD signal pulse from the current sense resistor,
therefore ZCD auxiliary winding is unneeded.
OCP comp.
GND
ZCD Vth
OUT
ZCD comp.
Error Amp Block
Dynamic
OVP
OVP
Feedback
input
Dynamic
OVP
R2A20113
Convention IC
(Without the
function)
Vcc Maximum
24V
Tj operation
-40 to 150deg.
Drive peak current
+/-0.9A
3．Dynamic OVP
R2A20113
390V
+
Open/Short Detector
Unneeded!
Unneeded!
Out put Voltage
Input Current
External open short detection circuit is unneeded
Turn-on of MOSFET at inrush timing is prevented
Applications
(2) ZCD line less
ＣＯＭＰ
FB
OUT
ＶＣＣ
ＲＴ
VREF
GND
(3) Reduce recovery diode loss
390V
19V
R2A20113
OCP
Renesas Critical Conduction Mode PFC IC
R2A20113
April 2010
R2A2012X
Acoustic noise
is reduced.
Acoustic noise
is reduced.
(1)AC high voltage line less
(1)AC high voltage line less
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