C0085C0067C0067C0049C0056C0048C0054
C0085C0067C0067C0050C0056C0048C0054
C0085C0067C0067C0051C0056C0048C0054
SLUS272C − FEBRUARY 2000 − REVISED JUNE 2003
C0076C0079C0087C0045C0080C0079C0087C0069C0082C0044 C0068C0085C0065C0076C0262C0079C0085C0084C0080C0085C0084C0044
C0067C0085C0082C0082C0069C0078C0084C0262C0077C0079C0068C0069 C0080C0087C0077 C0067C0079C0078C0084C0082C0079C0076C0076C0069C0082
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FEATURES
C0068 BiCMOS Version of UC3846 Family
C0068 1.4-mA Maximum Operating Current
C0068 100-µA Maximum Startup Current
C0068 ±0.5-A Peak Output Current
C0068 125-ns Circuit Delay
C0068 Easier Parallelability
C0068 Improved Benefits of Current Mode Control

DESCRIPTION
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
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.
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.
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 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
2
8
5
1
6
11
14
15
INV
AOUT
BOUT
VREF
CT
NI
CURLIM
UCC3806
10
9
SYNC
RT 4CS+
VIN
15 13
VC
7COMP
UCC3612
CS−
3 12
GND
UC39431
+V
IN
+V
OUT
SHUT
DOWN
C0080C0082C0079C0068C0085C0067C0084C0073C0079C0078 C0068C0065C0084C0065 C0105C0110C0102C0111C0114C0109C0097C0116C0105C0111C0110 C0105C0115 C0099C0117C0114C0114C0101C0110C0116 C0097C0115 C0111C0102 C0112C0117C0098C0108C0105C0099C0097C0116C0105C0111C0110 C0100C0097C0116C0101C0046
C0080C0114C0111C0100C0117C0099C0116C0115 C0099C0111C0110C0102C0111C0114C0109 C0116C0111 C0115C0112C0101C0099C0105C0102C0105C0099C0097C0116C0105C0111C0110C0115 C0112C0101C0114 C0116C0104C0101 C0116C0101C0114C0109C0115 C0111C0102 C0084C0101C0120C0097C0115 C0073C0110C0115C0116C0114C0117C0109C0101C0110C0116C0115
C0115C0116C0097C0110C0100C0097C0114C0100 C0119C0097C0114C0114C0097C0110C0116C0121C0046 C0080C0114C0111C0100C0117C0099C0116C0105C0111C0110 C0112C0114C0111C0099C0101C0115C0115C0105C0110C0103 C0100C0111C0101C0115 C0110C0111C0116 C0110C0101C0099C0101C0115C0115C0097C0114C0105C0108C0121 C0105C0110C0099C0108C0117C0100C0101
C0116C0101C0115C0116C0105C0110C0103 C0111C0102 C0097C0108C0108 C0112C0097C0114C0097C0109C0101C0116C0101C0114C0115C0046
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