BQ55090QTx27 DC-DC Converter

35-55 V

55 V

27 A

240 W

2000 V dc



Transient Input




DC-DC Converter

Product Details

The BusQor® BQ55090QTA27 bus converter is a next- generation, board-mountable, isolated, fixed switching frequencydc/dc converter that uses synchronous rectification to achieve extremely high conversion efficiency. The power dissipated by the converter is so low that a heatsink is not required, which saves cost, weight, height, and application effort. The BusQor series provides an isolated step down voltage from 48V to 12 or 9.6V intermediate bus with no regulation in a standard “quarter-brick” module. BusQor converters are ideal for creating the mid-bus voltage required to drive point-of-load (non-isolated) converters in intermediate bus architectures.

Operational Features

• High efficiency, 96 % at full rated load current at full load
• Delivers full power with minimal derating - no heatsink required
• Operating input voltage range: 36-55 V dc
• Fixed frequency switching provides predictable EMI
• No minimum load requirement

Mechanical Features

• Industry standard quarter-brick pin-out configuration (two or four output pin option)
• Size: 1.45” x 2.3” (36.8x58.4mm)
• Total height: 0.445” (11.3mm)
• Total weight: 1.5 oz (42 g)

Control Features

• On/Off control referenced to input side
• Inherent current share (by droop method) for high current and parallel applications.

Safety Features

• 2000 V input-to-output isolation
• UL 60950-1:2003
• CAN/CSA-C22.2 No. 60950-1:2003
• EN60950-1:2001
• Needle Flame Test (IEC 695-2-2)
• IEC 61000-4-2
• RoHS compliant (see page 14)

Protection Features

• Input under-voltage lockout and over-voltage shutdown protects again abnormal input voltages
• Output current limit and short circuit protection (auto recovery)
• Output over-voltage protection
• Thermal shutdown