Novel regulation makes dual DC/DCs more flexible

Edited by the Electronicstalk editorial team May 10, 2001

Datel's new BWR-5/3.3, 33W Series mixed-voltage, dual-output (3.3 and 5V) DC/DC convertors feature a novel output structure that does not limit output current in the traditional manner.

Datel's new BWR-5/3.3, 33W Series mixed-voltage, dual-output (3.3 and 5V) DC/DC convertors feature a novel output structure that does not limit output current in the traditional manner.

The 3.3V output can source any current from 0 to 7A, and the 5V output can source any current from 0 to 6A, as long as the total load does not exceed the 33W limitation of the of the device package.

Among other advantages, this power-sharing feature gives designers a "load polygon" within which to work.

It also enables fast moving designers to migrate a single proven power supply as they conceive newer systems with decreasing legacy 5V requirements and increasing 3.3V requirements.

Most dual-output DC/DC's employ a single control loop to regulate their primary output (usually the 3.3V output) as their auxiliary output "trails" along.

BWR-5/3.3, 33W duals employ a unique shared regulation architecture that fully regulates the 3.3V output while simultaneously regulating approximately 66% (3.3 divided by 5) of the 5V output.

This distinctive scheme enables devices to guarantee, for their 3.3 and 5V outputs, respectively, +/- 0.5 and +/- 1% line regulation and +/- 1 and +/- 1.5% load regulation.

Both 3.3 and 5V output stages exploit full synchronous rectification enabling these power converters to deliver an industry leading 88% efficiency.

High efficiency enables Datel to pack the full 33W of deliverable power into the industry-standard, 2 x 2 x 0.45in, five-sided shielded, metal case traditionally reserved for 20W units.

The 33W BWRs operate at full rated power over the -40 to +65C ambient temperature range and require no supplemental airflow.

Synchronous rectification also enables stable no-load operation, an important consideration for power-conscious applications in which selected partitions go into "sleep mode".

BWR-5/3.3, 33W duals include input pi filters, input overvoltage and undervoltage shutdown, output overvoltage protection, output current limiting, continuous short circuit protection, and thermal shutdown.

The functionality set includes Vout trim, remote on/off control and an optional sync function.