UC3845BN ,High performance current mode PWM controllerThermal CharacteristicsD Suffix, Plastic Package, SO–14 Case 751AMaximum Power Dissipation @ T = 25 ..
UC3845BVD ,High performance current mode controllerAND8039/DThe One-TransistorForward ConverterPrepared by: Marty Brown
UC3845BVN ,High Performance Current Mode ControllerOrder this document by UC3844B/D** ** * ** * * **The UC3844B, UC3845B series are high performance ..
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UC3845D1 ,SMPS ControllerBlock Diagram* NORMALLY 8DIP/8SOP PIN NO.* ( ) IS 14SOP PINNO.* TOGGLE FLIP FLOP USED ONLY IN UC384 ..
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UC2844BD-UC2845BN-UC3844BD-UC3845BD1-UC3845BN-UC3845BVN
High performance current mode controller
Order this document by UC3844B/D
ORDERING INFORMATION -
The UC3844B, UC3845B series are high performance fixed frequency
current mode controllers. They are specifically designed for Off–Line and
dc–to–dc converter applications offering the designer a cost–effective
solution with minimal external components. These integrated circuits feature
an oscillator, a temperature compensated reference, high gain error
amplifier, current sensing comparator, and a high current totem pole output
ideally suited for driving a power MOSFET.
Also included are protective features consisting of input and reference
undervoltage lockouts each with hysteresis, cycle–by–cycle current limiting,
a latch for single pulse metering, and a flip–flop which blanks the output off
every other oscillator cycle, allowing output deadtimes to be programmed
from 50% to 70%.
These devices are available in an 8–pin dual–in–line and surface mount
(SO–8) plastic package as well as the 14–pin plastic surface mount (SO–14).
The SO–14 package has separate power and ground pins for the totem pole
output stage.
The UCX844B has UVLO thresholds of 16 V (on) and 10 V (off), ideally
suited for off–line converters. The UCX845B is tailored for lower voltage
applications having UVLO thresholds of 8.5 V (on) and 7.6 V (off). Trimmed Oscillator for Precise Frequency Control Oscillator Frequency Guaranteed at 250 kHz Current Mode Operation to 500 kHz Output Switching Frequency Output Deadtime Adjustable from 50% to 70% Automatic Feed Forward Compensation Latching PWM for Cycle–By–Cycle Current Limiting Internally Trimmed Reference with Undervoltage Lockout High Current Totem Pole Output Undervoltage Lockout with Hysteresis Low Startup and Operating Current
