POWER SUPPLY DESIGN - Last Mile Gear

The Challenge

The first step in ControlTek’s design engineering process is always identifying which problems need to be addressed.

Last Mile Gear came to ControlTek looking to create two different versions (56V & 29V) of an injector (power supply with integrated GPS linked sync pulse injection) for use with communication systems. The power supplies had to accept input from a UGPS antenna, allow for USB control, and provide Gigabit Ethernet connection and 90W per channel of power to 4 radios simultaneously. Overcurrent protection was a must.

In addition, up to 8 of the injectors must be allowed to connect into a single stack via RS485, allowing for 32 total radios per stack. Each injector had to fit in a ½ width 1U rack mount enclosure and dissipate the thermal energy without the aid of a fan.

Our Solution

ControlTek’s design engineering team began with careful selection of the power module that would deliver energy to the system. This power module was the heart of the injector, around which the rest of the design was formed.

To reduce size and weight, ControlTek engineers designed planar transformers into the PCB of the 56V injector for the sync pulse circuits. The 29V version utilized a secondary processor to generate a precise sync pulse, triggered by the UGPS pulse. Our team then worked with Last Mile Gear to complete the design with heatsink and other mechanical components. 

Because ControlTek focuses on code reusability/portability, product development time was minimized. Several functions, including a full functioning bootloader, were dropped in with virtually no additional effort. Firmware development was also started on a development board so code was available for test the day prototype hardware was ready. RS485, USB, and Ethernet communications all operated together seamlessly.

The Results

By integrating ControlTek’s design team with Last Mile Gear and their customer, we were able to ensure the proper requirements for the system were implemented resulting in a robust, industry leading product and another successful design partnership.