ML4827
TYPICAL PERFORMANCE CHARACTERISTICS
250
200
150
100
50
250
200
150
100
50
0
–500
0
0
500
0
1
2
3
4
5
IEA INPUT VOLTAGE (mV)
V
(V)
FB
Voltage Error Amplifier (VEA) Transconductance (g )
Current Error Amplifier (IEA) Transconductance (g )
m
m
400
300
200
100
0
0
1
2
3
4
5
V
(mV)
RMS
Gain ModulatorTransfer Characteristic (K)
16
1
13
2µA
V
CC
VEAO
VEA
IEAO
POWER FACTOR CORRECTOR
BROKEN WIRE
V
V
CCZ
REF
V
REF
OVP
7.5V
REFERENCE
V
FB
13.5V
14
+
–
IEA
COMPARATOR
3.5kΩ
15
–
+
+
–
2.7V
1V
2.5V
AC
+
–
S
Q
I
+
–
2
4
3
–1V
+
–
GAIN
MODULATOR
V
R
S
Q
Q
RMS
PFC OUT
3.5kΩ
PFC I
I
LIMIT
12
SENSE
R
Q
RAMP 1
7
OSCILLATOR
Figure 1. PFC Section Block Diagram.
6