FAN6755UWMY Datasheet, PDF (8/17 Pages) Fairchild Semiconductor – mWSaver™ PWM Controller

Electrical Characteristics
VDD=15 V, TA=25C, unless otherwise noted.
Symbol
Parameter
Feedback Input Section
AV
ZFB
VFB-OPEN
VFB-OLP
tD-OLP
Internal FB Voltage Attenuation
Input Impedance
The Maximum Clamp of FB Voltage
FB Open-Loop Protection Triggering
Level
Delay Time of FB Pin Open-loop
Protection
VFB-N Green-Mode Entry FB Voltage
Conditions
V_FB=4 V
FB Pin Open
VFB-G Green-Mode Ending FB Voltage
VFB-ZDCR
FB Threshold Voltage for Zero-Duty
Recovery
VFB-ZDC FB Threshold Voltage for Zero-Duty
VFB-ZDCR -
VFB-ZDC
ZDC Hysteresis
Min. Typ.
Max. Unit
1/4.5
1/4.0
1/3.5
V/V
10
15
19
kΩ
5.1
5.3
5.5
V
4.4
4.6
4.8
V
45.0
62.5
70.0
ms
2.8
3.0
3.2
V
VFB-N - 0.6
V
1.6
1.8
2.0
V
1.4
1.6
1.8
V
0.12
0.15
0.19
V
Frequency
+ hopping range
f_OSC
- hopping range
PWM
Frequency
+1.76KHz
f_OSC-G
-1.76KHz
V_FB-ZDCV_FB-ZDCRV_FB-G
V_FB-N
V_FB
Figure 7. VFB vs. PWM Frequency
Continued on the following page…
© 2009 Fairchild Semiconductor Corporation
FAN6755W / FAN6755UW • Rev. 1.0.7
8
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