ML4824
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
IEAO
VEAO
VEA
OVP
V
FB
+
IEA
3.5kΩ
15
–
+
–
2.7V
–1V
–
+
–
2.5V
AC
+
S
Q
I
2
4
3
+
–
GAIN
MODULATOR
V
R
S
Q
Q
RMS
PFC OUT
3.5kΩ
PFC I
I
12
LIMIT
SENSE
R
Q
RAMP 1
OSCILLATOR
7
Figure 1. PFC Section Block Diagram.
6