Telecom Full-Bridge Quarter Brick DC/DC Converter
Created: May 17, 2016
No description available.
In the field of telecommunication supply industry, what became popular these days in terms of power supply are the Intermediate Bus Converters (IBCs) and most of the telecom and data communication systems uses ASIC, FPGAs and integrated high-end processors. These types of system require tight load regulations while having higher current at multiple of low-level voltages. The conventional Distributed Power Architecture (DPA) supply generates 24V/48V with individual isolated brick converter can support the required low system voltage yet this becomes inefficient and costly. On the other hand, IBCs can generate 12V/5V where these voltages are stepped down to the necessary load voltages by (PoLs) hence, the high-density power converters which are lower in costs pertains too much more improved performance. This features the digitally controlled power supply with two sides of control option, the primary and secondary.
This telecommunication supply circuit is comprised of several parts that are broken into four groups. The group A of the design illustrates the secondary side control that is comprised of high-speed MOSFET drivers with isolation requirement. It requires 2500Vdc isolation between primary to secondary side controller because the gate drive is derived from the secondary side controller that is also based on the gate drivers used. It has temperature-sensing device that is used to monitor the temperature and shuts down the converter when the quarter brick converter exceeds the maximum operating temperature. The group B is the primary side control that is comprised of several power MOSFETs compared to the secondary side control. The galvanic isolation is done by using optocouplers but it degrades over time and temperature. The transfer of signals from the primary to the secondary or the secondary to the primary is dependent on the features demanded by the application. The group C is the main controller of this design that is comprised of DSPIC33FJ16GS502-E/MX a Digital Signal Controller (DSC) IC and some passive components. The DSC provides the control digital signals as feedback to the signals that is received from the full bridge DC/DC converter circuit. It allows active load balancing in the parallel-connected systems and real time algorithms for the regulation of power converters. The group D is comprised of PWM controller that helps the generation of high operating frequencies with good resolution in which these PWM and some digital compensator will produce the desired control signal.
This design is fully suitable for telecommunication application that requires a compact DC/DC converter with capability of 200W with 12Vdc output. It is also applicable to some electrical line monitoring that requires a reliable digital system of monitoring, assuming that this design circuit is modified for monitoring. It is also applicable to instrumentation since it deals control systems and some switching operating.