R2A20111 Datasheet, PDF (1/1 Pages) Renesas Technology Corp – Renesas PFC Control IC for Digital-TV

Renesas PFC Control IC for Digital-TV
R2A20111
April 2010
Features
1. Continuous conduction mode is suitable for the system with large
and high frequency variation of current.
2. Easy design by separate current terminal.
3. Hold function countermeasure to AC temporary blackout.
It is possible to set no soft start time by chip capacitor.
4. Feed back loop detector.
5. Soft start period become short by quick soft start function.
6. Improve the load regulation by gm Amp at feed back Amp.
OUT
GND
DELAY
CGND
CAI
VREF
CAO
CLIMIT
DIP16
or
SOP16
VCC
SS
EO
FB
IAC
PFC-ON
CT
RT
1. Continuous conduction mode suitable for the system 2. Easy design by separate current terminal
Input average current
Input voltage
Advantages
Weaknesses
• Small radiation noise • A little bit complex
Choke coil current
• Small peak current circuit.
• Non-influenced of
Continuous conduction modceurrent change.
• Simple circuit
Critical conduction mode
(Discontinuous)
• Large radiation noise
• Large peak current
• Large choke coil
Conventional
Multi
CS C-AMP
C-limiter
R2A20111
V-AMP
FB
EO
Constant
power
limiter
CAI ^Multi
VREF
C-AMP
CLIMIT
C-limiter
lout change case
Possible to set no coil vibration at start up and current limit.
In case of continuous
4. Feed back loop detector
current mode, not so much
change peak current.
Built in over voltage protection.
And feedback loop absence detection can stop output pulse and PG.
In case of critical current
Therefore bulk capacitor & FET is not broken by R2A20111.
mode, the peak current
is so large.
Large current change
3. Hold function countermeasure to AC temporary blackout
AC input
AC blackout
Hold counter
Hold timer (Adjustable)
Conventional
Bulk voltage
In case of feed back
loop down, bulk
voltage rise up to
cut
abnormal voltage. And cut
capacitor is broken.
FB Conventional IC
FB
w/o this function
R2A20111
Bulk voltage
The feed back loop
disconnection is detected,
and stop pulse!
Prevention from destruction
of bulk capacitor and power
MOSFET!
R2A20111
Bulk voltage
FET OUT
(R2A20111)
FET OUT
(Conventional IC)
IC operation does not stop for set period, therefore recovery is
faster, available in the area where power supply is not stable.
6. Improve load regulation by gm Amp at feed back Amp
In voltage feedback Amp case, feedback current flow
influence to load regulation.
Conventional
R2A20111
5. Soft start period become short by quick soft start function^VOUT
VOUT
Soft start voltage
Css=4.7uF
Improved time=4.7uFX1V/25uA=188ms.
R2
R1
Triangle wave
Renesas
General soft start period
Error Amp
VEO
VREF
R2
FB _{Error Amp}
R1
VREF
Example of Application Circuit
Small & high reliability systems
• Target power range is over 300V.
• Realize high reliability on PFC block by R2A20111 and
coordinate next stage by P.G.
• Realize small transformer and high efficiency by using
half bridge topology by HA16150.
R2A20111
RJK5015
380V
+
HA16150
RJK5015
12V
5V
HA16116
Renesas Electronics URL http://www.renesas.com/pfcic
Possible to use 500V type FET
Down sizing trance
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