Lime AC (Active Cooling) Cases are designed for LimeSDR users who want to better manage heat generated by their devices. The cases also make LimeSDRs more portable - protecting the PCB from damage - while they provide RF shielding for enhanced performance. We designed one case for the LimeSDR Mini and three versions for the LimeSDR USB Type-A.

For LimeSDR Mini

• Compatible with both LimeSDR Mini v1.1 and v1.2
• All major chips are connected to the case by 1 mm thick thermal silica pads
• Active cooling fan included
• LED indicator visible through the top of the case
• Fully-shielded - the vulnerable USB socket is especially protected

Installation note: For the v1.0 cases (manufactured during the campaign): In order to install a LimeSDR Mini in the case, the on-board RF shield must be desoldered. This allows for proper thermal conductivity. An RF shielding sponge replaces the functionality of the on-board shield.

For the v1.1 case (available after Sep 2020): we changed the heat dissipation solution for the LMS7002 chipset by connecting the original RF shield to the case, and connecting the chipset to the RF shield with the thermal pad. Previously, the chipset was directly connected to the case through a custom made RF shield. We made this change so that the heat dissipation solution won’t have any negative effect on the RF performance.

The new solution looks like a sandwich:

| top case | thermal pad | RF Shield | thermal pad | LMS7002 |

For LimeSDR USB Type-A

Lime AC Tetra Case

• All major chips are connected to the case by thermal silica pads
• On-board U.FLs routed to external SMA connectors - appropriate cables included
  • 2 SMAs towards the USB port - intended for CLK signals
  • 10 SMAs towards the rear - intended for RF signals
• LED indicators light-piped to the USB side of the case
• Fully-shielded - the vulnerable USB socket is especially protected
• All on-board RF and CLKs are made externally available
• Radiator fins and active-cooling fan
• 4 M3-5 mm mounting holes

Protect Your Board

The PCB is tightly clamped in the case. The LimeSDR Mini fits snugly in its case, while the LimeSDR-USB Type-A is fixed to the base case with screws. This design will prevent your board from being damaged if it happens to fall while installed in the case.

Active Cooling with Fan

Anyone who uses a LimeSDR Mini for an extended period of time knows that it gets pretty hot. That’s why we added a fan to actively cool your LimeSDR so you can keep using it longer and without fear of heat damage (to the board or your hands). The fan is detachable from the case, if you don’t want to use it all the time.

RF Shielding

The full LimeSDR board is shielded by the aluminum case to isolate external electromagnetic interference.

*The case shown here is the Lime AC Tetra Case.

LED Indicators

LimeSDR boards have indicator LEDs that are quite useful, so we wanted to be sure those are still properly visible in the cases. So those LEDs are sent through light pipes to the outside of the case. Our philosophy is that once the case is assembled, you’ll never have to disassemble it.

Secure Mounting Holes

There are four M3 size mounting holes on the bottom base in 1.1 version (1.1 version cases began being sold in September 2020), so that you can easily mount the case in your product.

Comparison Table

How does the Lime AC Case compare to other available cases?

Aluminum Case Development

Along with thousands of other people, we are big supporters of the LimeSDR and LimeSDR Mini devices. But in our extended daily use, we noticed a few things that could be improved. As the SDR is a naked PCB, it can be damaged easily. Plus, the board generates a lot of heat - so much that you can’t even touch it after long-term use. So we decided to do something to solve these problems. First, we made a passive cooling case which you can see below.

This case worked well, so we took our design even further and added a fan for active cooling.