SG6846B Fairchild Semiconductor, SG6846B Datasheet - Page 8

• Manufacturer Part Number: SG6846B
• Description: The highly integrated PWM controller, SG6846B, provides several features to enhance the performance of fly-back converters
• Manufacturer: Fairchild Semiconductor

© 2008 Fairchild Semiconductor Corporation
SG6846B • Rev. 1.3.4
PWM Output Section
Over-Temperature Protection (OTP) Section
R
Electrical Characteristics
V
Note:
1.
t
I
DD
Symbol
DOTP-LATCH
DCY
R
Section
V
V
RI
RI
RI
= 15V and T
V
RT-OFF
V
CLAMP
The relationship between R
I
RTTH
t
t
RT
NOR
MAX
OH
OL
R
F
MIN
MAX
Maximum Duty Cycle
Output Voltage Low
Output Voltage High
Rising Time
Falling Time
Gate Output Clamping Voltage
Output Current of RT Pin
Threshold Voltage for OTP
Over-Temperature Latch-off Debounce
Equivalent Impedance of RT for OTP
R
Maximum R
Minimum R
I
A
Operating Range
= 25°C unless otherwise noted.
I
I
Value for Protection
Value for Protection
Parameter
RT-OFF
(Continued)
and R
I
is:
R
RT
(1)
(1)
-
OFF
=
8
V
V
V
GATE = 1nF
GATE = 1nF
V
R
SG6846BLSY or
SG6846BCSY,
R
SG6846BLSZ or
SG6846BCSZ,
R
R
OTP
DD
DD
DD
I
I
I
I
Test Condition
= 26kΩ
= 26kΩ, V
= 26kΩ, V
= 26kΩ
-
LATCH
= 15V, I
= 12V, I
= 20V
-
OFF
O
O
FB
FB
I /
= 50mA
= 50mA
>V
>V
RT
N
N
=
V
RT
/
Min.
1.00
(70
80
64
14
13
10
8
μ
A
×
Typ.
1.05
350
100
100
26
85
50
70
15
/
R
I
(K
Max.
1.10
1.5
90
18
76
16
36
Ω
6
www.fairchildsemi.com
))
Unit
MΩ
µA
ms
kΩ
kΩ
kΩ
ns
ns
µs
%
V
V
V
V
(1)