B3843 Datasheet, PDF (1/10 Pages) List of Unclassifed Manufacturers – Current Mode PWM Controller

Bay Linear
Inspire the Linear Power
Current Mode PWM Controller
B3842/43/44/45A&A1
Description
The Bay Linear B3842/43/44/45 are fixed frequency current-
mode PWM controller. These devices are designed for Off-
Line and DC-to-DC converter applications with minimum
external components. The B3842 family Feature a trimmed
oscillator for precise duty cycle control, a temperature
compensated reference, high gain error amplifier, current
sensing comparator, and a high current totempole output.
Ideally suited for driving a power N-Channel MOSFET’s. It is
low when is on off stage. Protection circuitry includes built in
under-voltage lockout and current limiting.
Major differences between members of these series are the
UVLO thresholds and maximum duty-cycle ranges. Typical
UVLO thresholds of 16V (on) and 10V (off) on the B3842 and
B3844 devices make them ideally suited to off-line
applications. These corresponding typical thresholds for the
B3842 and B3845 devcies are 8.4V (on) and 7.6V (off). The
B3842 and B3843 devcies can operate to duty cycles
approaching 100%. A duty-Cycle range of 0 to 50% is
obtained by the B3844 and B3845 by the addition of an
internal toggle flip-flop, which blanks the output off every
other clock cycle. It id available in 8 pin DIP and SOIC
packages.
Features
• Low Start-Up and Operating Current
• Maximum Duty Cycle
• Operating Frequency Up to 500KHz
• Under voltage Lockout with Hysteresis
• Available in 8 pin SOIC
• Similar to industry Standard UC3842
Applications
• Switching Power Supply
• Monitor
Pin Connection
8-Pin Surface Mount
COMP
1
8
REF
NC
2
7
VCC
ISENSE
RT/CT
3
6
4
5
Top View
OUTPUT
GND
Ordering Information
Devices
B384X(Z)M
B384X(Z)P
Z=A ON Semi
Package
Temp.
SO-8
0 °C to 70 °C
8-DIP
0 °C to 70 °C
Z=A1 Fairchild & Samsung
Bay Linear, Inc 2418 Armstrong Street, Livermore, CA 94550 Tel: [phone], Fax: [phone]
www.baylinear.com