FAN4800 Fairchild Semiconductor, FAN4800 Datasheet - Page 8

• Manufacturer Part Number: FAN4800
• Description: Low Start-Up Current PFC/PWM Controller Combos
• Manufacturer: Fairchild Semiconductor

FAN4800 Rev. 1.0.5
© 2005 Fairchild Semiconductor Corporation
Typical Performance Characteristics
Figure 5. Gain Modulator Transfer Characteristic (K)
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
126
119
112
105
98
91
84
77
70
63
56
0.0 0.5 1.0 1.5 2.0 2.5
Figure 3. Voltage Error Amplifier (gmv)
2.0 2.1 2.2 2.3 2.4 2.5
K
=
Transconductance
I
GAINMOD
I
AC
×
(6 0.625)
V
−
−
V
RMS
I
FB
OFFSET
(V)
(V)
3.0 3.5 4.0 4.5 5.0
2.6 2.7 2.8 2.9 3.0
mV
−
1
(1)
8
100
-10
2.2
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
90
80
70
60
50
40
30
20
10
0
0.0
-0.8
Figure 4. Current Error Amplifier (gmi)
0.5
-0.6
1.0
Figure 6. Gain vs. V
-0.4
1.5
Transconductance
Gain
2.0 2.5 3.0 3.5 4.0 4.5 5.0
-0.2
I
SENSE
V
=
RMS
I
SENSE
0.0
(V)
(V)
I
−
AC
0.2
I
OFFSET
RMS
0.4
0.6
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0.8
(2)