AHF28XX

· 16 to 40 VDC Input Range (28 VDC Nominal)
· Single and Dual Outputs
· 12 Watts Output Power
· 22.8 W/in3 Power Density
· Low Input / Output Noise (50mA/60mVp-p max. respectively)
· Indefinite Short Circuit and Overload Protection
· Wideband Control Loop for Superior Transient Characterstics
· No Derating for -55°C to +125°C Opertation
· Constant Switching Frequency (550KHz Nominal)

The AHF Series of DC/DC converters feature single or dual outputs over the full military temperature range.No derating in output power is required, making them suitable for use in rugged military applications. The low profile, small outline package is ideally suited to the tight board space requirements of many industrial and aerospace applications. Designed for nominal 28Vdc inputs, this AHF Series of converters will meet the requirements of MIL-STD-704D. The basic circuit utilizes a pulse width modulated, feed-forward topology at a nominal switching frequency of 550KHz. Input to output isolation is achieved through the use of transformers in the forward and feedback circuits.

The proprietary magnetic feedback circuit provides for an extremely wide bandwidth control loop with a high phase margin. The closed loop frequency response of this converter family extends to approximately 50KHz,resulting in superior line and load transient characteristics.This feedback method is also inherently temperature and radiation insensitive. This gives the AHF Series an important advantage over converters that incorporate opto-couplers in their design.

These AHF Series converters are manufactured in a facility certified to MIL-PRF-38534. All processes used to manufacture these converters have been qualified to enable Advanced Analog to deliver compliant devices. Four screening grades are available to satisfy a wide range of requirements. The CH grade converters are fully compliant to MIL-PRF-38534 class H. The HB grade converters are processed to full MIL-PRF-38534 screening but do not have class H element evaluation as required by MIL-PRF-38534. Two grades are fully tested and operate the full military temperature range without derating of output power. Industrial and commercial grades are also available. Variations are electrical,mechanical and screening can be accommodated.

Extensive computer simulation using complex modeling enables rapid design modification to be provided. Contact Advanced Analog with specific requirements in AHF Series.