SG6858 Fairchild Semiconductor, SG6858 Datasheet - Page 5

• Manufacturer Part Number: SG6858
• Description: This highly integrated PWM controller provides several special enhancements designed to meet the low standby power needs of low-power SMPS
• Manufacturer: Fairchild Semiconductor

© 2008 Fairchild Semiconductor Corporation
SG6858 • Rev. 1.2.4
V
Feedback Input Section
Current Sense Section
Oscillator Section
Output Section
Electrical Characteristics
V
V
DD
DD
Symbol
V
GATE-CLAMP
t
V
DCY
DCY
V
V
V
V
D-VDDOVP
Z
V
V
V
V
f
DD-G OFF
=15V, T
I
FB-OPEN
V
V
I
OSC-G
GATE-H
DD-OVP
f
GATE-L
Section
DD-OFF
DD-ST
DD-OP
SENSE
STHVA
t
Z
STHFL
DD-ON
DD-OP
t
OSC
f
f
A
S
LEB
FB-N
FB-G
PD
DV
t
t
DT
FB
R
F
G
V
SAW
MAX
A
=-40°C ~+125°C (T
Input Impedance
Delay to Output
Flat Threshold Voltage for Current Limit
Valley Threshold Voltage for Current Limit
Leading-Edge Blanking Time
Duty Cycle of SAW Limit
Frequency
Green Mode Frequency
Frequency Variation vs. V
Frequency Variation vs. Temperature
Deviation
Maximum Duty Cycle
Output Voltage Low
Output Voltage High
Rising Time
Falling Time
Output Clamp Voltage
FB Input to Current Comparator Attenuation
Input Impedance
FB Pin Open High Voltage
Green Mode Entry FB Voltage
Green Mode Ending FB Voltage
Green Mode Modulation Slope
Continuously Operating Voltage
Turn-On Threshold Voltage
Turn-Off Voltage
Startup Current
Operating Supply Current
V
V
V
Off Mode
DD
DD
DD
Over-Voltage Protection Level
OVP Debounce Time
Low Threshold Voltage to Exit Green
Parameter
A
= T
J
), unless otherwise specified.
DD
Deviation
5
V
V
1nF to GND
R
Maximum Duty
Cycle
R
R
V
T
V
V
I
V
V
V
O
A
DD
DD
DD
DD
DD
DD
DD
DD
I
I
I
Test Condition
=20mA
=95kΩ
=95kΩ
=95kΩ
=-40°C ~+125°C
=V
=15V, GATE with
=13.5V to 22V
=15V, I
=13.5V,
=13.5V, C
=13.5V, C
=13.5V, T
DD-ON
O
– 0.1V
=20mA
A
L
L
=25°C
=1nF
=1nF
V
+ 0.95
Min.
0.75
15.5
10.5
DD-OFF
240
100
4.5
23
50
10
65
70
35
16
0
8
V
+ 1.10
Typ.
16.5
11.5
2.85
2.20
0.96
0.80
0.02
DD-OFF
300
170
125
2/5
5.0
2.5
75
60
45
70
22
75
55
17
10
25
5
V
+ 1.25
Max.
17.5
12.5
0.85
2.00
DD-OFF
200
110
360
240
3.5
5.5
1.5
22
15
26
75
80
75
18
2
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Hz/mV
Unit
µsec
kHz
kHz
V/V
mA
kΩ
kΩ
µA
ns
ns
ns
ns
%
%
%
%
V
V
V
V
V
V
V
V
V
V
V
V
V