Datasheet

UCC28C40, UCC28C41, UCC28C42, UCC28C43, UCC28C44, UCC28C45
UCC38C40, UCC38C41, UCC38C42, UCC38C43, UCC38C44, UCC38C45
SLUS458E -- AUGUST 2001 -- REVISED OCTOBER 2010
4
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electrical characteristics V
DD
= 15 V (See Note 1), R
T
=10kΩ,C
T
=3.3nF,C
VDD
=0.1μF and no load
on the outputs, T
A
=--40°C to 105°C for the UCC28C4x and T
A
=0°Cto70°C for the UCC38C4x,
T
A
=T
J
(unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNITS
Output Section
V
OUT
low (R
DS(on)
pull-down) I
SINK
= 200 mA 5.5 15
Ω
V
OUT
high (R
DS(on)
pull-up) I
SOURCE
= 200 mA 10 25
Ω
Rise tIme T
A
=25°C, C
LOAD
=1nF 25 50
n
s
Fall time T
A
=25°C, C
LOAD
=1nF 20 40
ns
Undervoltage Lockout Section
UCC38C42, UCC38C44 13.5 14.5 15.5
Start threshold
UCC38C43, UCC38C45 7.8 8.4 9.0
S
t
a
r
t
t
h
r
e
s
h
o
l
d
UCC38C40, UCC38C41 6.5 7.0 7.5
V
UCC38C42, UCC38C44 8 9 10
V
Minimum operating voltage
UCC38C43, UCC38C45 7.0 7.6 8.2
M
i
n
i
m
u
m
o
p
e
r
a
t
i
n
g
v
o
l
t
a
g
e
UCC38C40, UCC38C41 6.1 6.6 7.1
PWM Section
M
a
x
i
m
u
m
d
u
t
y
c
y
c
l
e
UCC38C42, UCC38C43, UCC38C40, V
FB
<2.4V 94% 96%
Maximum duty cycle
UCC38C44, UCC38C45, UCC38C41, V
FB
<2.4V 47% 48%
Minimum duty cycle V
FB
>2.6V 0%
Current Supply Section
Start-up current (I
START-UP
) V
DD
= Undervoltage lockout start threshold (--0.5 V) 50 100 μA
Operating supply current (I
DD
) V
FB
=V
CS
=0V 2.3 3.0 mA
NOTE 1: Adjust V
DD
above the start threshold before setting at 15 V.
1
2
3
4
8
7
6
5
COMP
FB
CS
RT/CT
VREF
VDD
OUT
GND
PDIP (P) or SOIC (D) PACKAGE
(TOP VIEW)
MSOP (DGK) PACKAGE
(TOP VIEW)
VREF
VDD
OUT
GND
8
7
6
5
1
2
3
4
COMP
FB
CS
RT/CT