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SLUS272C − FEBRUARY 2000 − REVISED JUNE 2003
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for applications ranging from off-line power
supplies to battery operated portable equipment.
Dual high-current, MOSFET driving outputs and a
fast current sense loop further enhance device
versatility.
FEATURES
D
D
D
D
D
D
D
BiCMOS Version of UC3846 Family
1.4-mA Maximum Operating Current
100-µA Maximum Startup Current
0.5-A Peak Output Current
125-ns Circuit Delay
All the benefits of current mode control including
simpler loop closing, voltage feed-forward,
parallelability with current sharing, pulse-by-pulse
current limiting, and push/pull symmetry
correction are readily achievable with the
UCC3806 series.
Easier Parallelability
Improved Benefits of Current Mode Control
DESCRIPTION
These devices are available in multiple package
options for both through-hole and surface mount
applications; and in commercial, industrial, and
military temperature ranges.
The UCC3806 family of BiCMOS PWM controllers
offers exceptionally improved performance with a
familiar architecture. With the same block diagram
and pinout of the popular UC3846 series, the
UCC3806 line features increased switching
frequency capability while greatly reducing the
bias current used within the device. With a typical
startup current of 50 µA and a well defined voltage
threshold for turn-on, these devices are favored
The UCC3806 is specified for operation from
−55°C to 125°C, the UCC2806 is specified for
operation from −40°C to 85°C, and the UCC3806
is specified for operation from 0°C to 70°C.
SIMPLIFIED APPLICATION DIAGRAM
+V
OUT
+V
IN
UC39431
15
13
VIN
VC
UCC3612
UCC3806
2
VREF
INV
6
7
COMP
8
5
1
CT
NI
AOUT 11
BOUT 14
CURLIM
SHUT
15
10 SYNC
DOWN
9
RT
CS− GND
12
CS+ 4
3
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Copyright 1999 − 2003, Texas Instruments Incorporated
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ꢞ ꢢ ꢟ ꢞꢗ ꢘꢬ ꢚꢙ ꢝ ꢥꢥ ꢣꢝ ꢛ ꢝ ꢜ ꢢ ꢞ ꢢ ꢛ ꢟ ꢧ
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