Electrical Characteristics (Continued)
VDD = 15V, TA = 25°C, unless noted.
Symbol
Parameter
Oscillator Section
Center
fOSC
Normal PWM Frequency Frequency
Jitter Range
fOSC,MAX
Maximum PWM
Frequency
Center
Frequency
Jitter Range
fOSC,MIN
Center
Minimum PWM Frequency Frequency
Jitter Range
thop-1
thop-3
fOSC-G
VFB-N
Jitter Period
Jitter period
Green-mode Minimum Frequency
FB Pin Frequency Pin, FB voltage
Reduction Threshold Jitter Range
VFB-G
Pin, FB voltage
FB Voltage at fOSC-G
Jitter Range
SG
Slope for Green-Mode Modulation
fDV
Frequency Variation vs. VDD Deviation
fDT
Frequency Variation vs. Temperature
Deviation
Test Condition Min. Typ. Max. Unit
RI = 26kΩ, VFB>VN
62
65
68
kHz
±3.7 ±4.2 ±4.7
RI = 13kΩ, VFB>VN
124 130 136
kHz
±7.4 ±8.4 ±9.4
RI = 36kΩ, VFB>VN
RI = 26kΩ, VFB ≥ VN
RI = 26kΩ, VFB = VG
RI = 26kΩ
RI = 26kΩ, VFB = VN
RI = 26kΩ, VFB = VG
RI = 26kΩ
VDD = 11.5V to 20V
TA = -30 to 85°C
44.8
±2.54
3.9
10.2
18.0
1.9
3.7
1.4
1.27
47.0
±2.90
4.4
11.5
22.5
2.1
4.2
1.6
1.45
85
1.5
49.2
±3.26
4.9
12.8
25.0
2.3
4.7
1.8
1.62
5
kHz
ms
ms
kHz
V
KHz
V
KHz
Hz/mV
%
5.0
%
Continued on following page…
Figure 5. PWM Frequency
© 2007 Fairchild Semiconductor Corporation
SG6846C • Rev. 1.1.2
6
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