TDK-Lambda i6A24008A033V-N00-R DC-DC Converter Inp:+9 to +40Vdc Out:-3,3 to -30Vdc 8Amp
 50 watts 14 A in a 1/16 brick package   Very high efficiency up to 98%   Wide output adjustment from 3.3 to 24V   Minimal external components needed 
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