Global Sources
EE Times-Asia
Stay in touch with EE Times Asia
 
EE Times-Asia > Power/Alternative Energy
 
 
Power/Alternative Energy  

PWM controller integrates programmable volt-second clamp

Posted: 09 May 2014  Print Version  Bookmark and Share

Keywords:Linear  converter  active clamp  PWM 

Linear Technology Corporation has launched a current-mode PWM controller for use in a synchronous forward converter with active clamp reset, allowing up to 100V input operation for power levels up to 400W.

The LT3753 has a programmable volt-second clamp, which enables primary switch duty cycles above 50 per cent for high switch, transformer, and rectifier utilisation. When the volt-second clamp is set above the natural duty cycle of the converter, it provides a duty cycle guardrail to limit primary switch reset voltage and prevent transformer saturation during load transients.

Linear LT3753

The LT3753 is an active clamp synchronous forward controller with a volt-second clamp and input voltage range of 8.5V to 100V.

The volt-second clamp also limits maximum VOUT if the opto path breaks open or, alternatively, defines VOUT in no-opto applications. For non-isolated high step-down ratio applications, the cevice contains a voltage error amplifier, allowing a very simple non-isolated fully regulated synchronous forward converter.

Additional features include programmable over-current protection, adjustable input under-voltage, and over-voltage lockout along with built-in thermal shutdown. The device has a programmable 100kHz to 500kHz operating switching frequency and can be synchronised to an external clock, allowing the use of a wide range of output inductor values and transformer sizes.

The controller is available in a TSSOP-38 package with several pins removed for high voltage spacing.





Article Comments - PWM controller integrates programmab...
Comments:  
*  You can enter [0] more charecters.
*Verify code:
 
 
Webinars

Seminars

Visit Asia Webinars to learn about the latest in technology and get practical design tips.

 
 
Back to Top