Regulator Replacement

Rev 7

The Recom module offered an easy solution to PCB layout and design, but didn't have very good performance at light loads and had an inductor that frequently broke during assembly or testing. To mitigate these, a new regulator design using the LMZM23601 regulator module from TI. This is a much smaller design that can supply up to 1 A of current with good regulation and low voltage ripple at low currents.

Voltage Regulation and Efficiency plots were created using a Rev 7 controller board that's powered by a power supply and is loaded using a BK 8600 E-Load. The voltage drop is mostly caused by the ideal diode IC.

These charts are in HW-189 and HW-190.

Rev 5 & Rev 6

Unfortunately, our previous regulator (AP65200) is out of stock and looking like it's EOL. We plan on switching to a power module/DC-DC to hopefully save space and allow for a 2-layer board.

Our goal is to find a max 16V to 3.3V converter at around 500mA peak. We're assuming that nothing too powerful will be running off of the 3.3V rail, so 500mA gives us a bit of overhead for the CAN transceiver, MCU, and LEDs present on the controller board.

Options

The options below are reasonably priced and have relatively low output ripple at light loads.

Outcome

Based on cost, the Recom power module is the best fit. We were able to fit it onto the Rev5 controller board.

In the case that the controller board is updated in such a way that the module no longer fits, the TI controller is a very interesting alternative that would be more flexible.