ATR28XXT

The ATR28XXT Series of DC/DC converters provide 30 watts of output power over the full military tempera-ture range with no derating.  These devices are pin compatible with the Advanced Analog ATO series con-verters but offer twice the maximum output power in a lower profile package.  A custom CMOS ASIC pulse width modulator operating at a nominal switching fre-quency of 550KHz combined with a unique magnetic feedback reduces circuit complexity for enhanced reli-ability.  These converters provide 500 volt input to out-put isolation and operate in highly efficient single for-ward mode.

The ATR28XXT advanced feedback design and high operating fre-quency provide an extremely wide bandwidth control loop with high gain and phase margin.  This results in fast dynamic line and load response as well as supe-rior audio rejection.  The control loop is compensated to provide optimum performance over the full military temperature range and over the 16 to 40 volt input voltage range.

These ATR28XXT converters are protected against both continu-ous output short circuits and output overload.  Either load fault condition will result in operating in a low power dissipation foldback mode.  The converters will shut down for approximately 15 milliseconds, then attempt to restart.  This cycle will continue indefinitely unless the load fault is corrected.  Recovery to normal opera-tion is automatic upon removal of the load fault.

Manufactured in a facility full qualified to MIL-PRF-38534, these converters ATR28XXT are available in four screen-ing grades to satisfy a wide range of requirements.  The CH grade is fully compliant to the requirements of MIL-PRF-38534 for class H.  The HB grade is processed and screened to the class H requirement, but element evaluation and Periodic Inspections (PI) are not re- quired.  Both grades are tested to meet the complete group "A" test specification over the full military tem-perature range without output power deration.

Two grades with more limited screening are also available by ATR28XXT for use in less demanding applications. Variations in electrical, mechanical and screen-ing can be limited accomodated. Contact Advanced Analog with specific requirements.