High Performance Current Mode Controllers

 

 

 

The UC3844B, UC3845B series are high performance fixed frequency

current mode controllers. They are specifically designed for Off−Line

and dc−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 (SOIC−8) plastic package as well as the 14−pin plastic surface

mount (SOIC−14). The SOIC−14 package has separate power and

ground pins for the totem pole output stage.

The UCX844B has UVLO thresholds of 16V (on) and 10V (off), ideally

suited for off−line converters. The UCX845B is tailored for lower voltage

applications having UVLO thresholds of 8.5V (on) and 7.6V (off).

 

 

 

Features

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

These Devices are Pb−Free and are RoHS Compliant

NCV Prefix for Automotive and Other Applications Requiring

Unique Site and Control Change Requirements; AEC−Q100

Qualified and PPAP Capable

 

 

 

Because of wholesale price is different from sample price, our website ca not state Please send your required part number via emai to Sales@hkmjd com or add our skype id mjdccm898 for online talking  As we as welcome you ca us : 0755-83957301 We wi send offer for you;  Sometimes manufacturer's price is unstable,so we don't adjust price i time  if you fee price is a little high for you,just fee free to contact us for consultatio  Thank you for your support ！

 

 

 

批發(fā)與零售價位不同,無法一一明示,詳情請通過郵件或客服咨詢(國內(nèi)銷售部電話:0755-83957301,企業(yè)QQ: 2850151585), 由于電子元器件價格不穩(wěn)定,時常有稍許變動,本公司未能及時調(diào)整,如您覺得售價不適，請與我們說明并適當議價,謝謝支持。