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Product Specification
Low-Power Green-Mode PWM Flyback Power Controller without Secondary Feedback
SG6849
© System General Corp.
- 5 -
www.sg.com.tw
Version 1.0(IRO33.0002.B3)
Dec.29, 2003
Current Sense Section
Symbol Parameter
Test Condition
Min.
Typ.
Max.
Unit
TPD
Propagation Delay
100
ns
VDD = 20V
0.84
0.89
0.94
V
VDD = 15V
0.72
0.77
0.82
V
Current Limiting Valley Threshold Voltage for 65kHz
VDD = 10V
0.58
0.63
0.68
V
VDD = 20V
0.76
0.81
0.86
V
VDD = 15V
0.65
0.70
0.75
V
VTH,VA
Current Limiting Valley Threshold Voltage for 100kHz
VDD = 10V
0.52
0.57
0.62
V
Oscillator Section
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
FOSC
SG6849–65 Frequency
60
65
70
kHz
FOSC
SG6849–100 Frequency
92
100
108
kHz
FOSC-G-BK
Green-Mode Burst Back Frequency*
20
25
30
kHz
FOSC-G-OFF
Green-Mode OFF Frequency*
0
kHz
IFB-G-OFF
Green-Mode OFF FB Input Current
0.9
1.15
1.4
mA
FDV
Frequency Variation versus VDD Deviation
VDD = 10 to 20V
2
%
VDD-TH-G
VDD-Low Threshold Voltage for Exiting Green-Mode
OFF
VDD
OFF+1.0
VDD
OFF+1.5
VDD
OFF+2.0
V
*Please see the “Green-Mode Burst Back (FOSC-G-BK) and Green-Mode OFF Frequency (FOSC-G-OFF) vs. VDD” curves.
0.77V
VLIMIT Ramp
TOFF
TON
Low-Line Sense
Voltage
High-Line
Sense Voltage
0V
T1
T2
VTH,VA
VTH,FT