Joining PCBs for Power Applications

[gmr1981]

Hi,

I'm designing a product that uses a buck/boost converter that can handle about 10A, input voltages range from 10V to 60V and output voltages are nominal 24V.

I want to structure the system so that several 10A buck/boost boards can be mounted on to a motherboard and their power connections connect to that - but the boards need to be detachable. The buck/boost board is entirely surface mount. I was thinking some kind of conductive pillars and copper screws? Anyone got any suggestions for connection hardware like this?

Thanks,
Greg

[uer166]

10A is not much. You can easily use 3-5 pins of a standard 100mil header for this, or choose from other SMT connectors. If the board is top single-side SMT, you can get through-board female headers and let the male side (which is soldered to motherboard) poke through your converter PCB.

[Siwastaja]

Classic card edge connectors (think ISA bus), or 0.100" pitch pin headers. Such solutions are typically rated for about 2A/contact, check the datasheet. Parallel enough pins + a few extra and you are done.

[tooki]

Hi,

I'm designing a product that uses a buck/boost converter that can handle about 10A, input voltages range from 10V to 60V and output voltages are nominal 24V.

I want to structure the system so that several 10A buck/boost boards can be mounted on to a motherboard and their power connections connect to that - but the boards need to be detachable. The buck/boost board is entirely surface mount. I was thinking some kind of conductive pillars and copper screws? Anyone got any suggestions for connection hardware like this?

Würth has a bunch of solder-in standoffs and the like that lend themselves to being used for this. Fundamentally, even ordinary brass standoffs, screwed to PCB pads, will work, though you definitely want to have generous pads to ensure plenty of contact surface, and possibly lots of vias in the pad to provide current carrying capacity.

But don’t discount the suggestion above to use normal headers (which you can also get in larger versions, and in versions with latching connectors). For example, Molex KK uses a friction latch and has both male and female PCB headers that would give you a substantial amount of retention force.

Are you under any particular space constraints?

[thermistor-guy]

10A is not much. You can easily use 3-5 pins of a standard 100mil header for this, or choose from other SMT connectors. If the board is top single-side SMT, you can get through-board female headers and let the male side (which is soldered to motherboard) poke through your converter PCB.

I use Amphenol D-sub connectors on my test jigs. Contacts are rated at 3A each, so a high-density 15-way connector can handle a lot of current, in principle.

For some prototyping and one-off applications, I drill out the connector shells at the screwlock holes. The shells then separate, making the contacts (through-hole
male and female) available as loose parts. The loose parts are useful when you want to make low pin count, board-to-board connections, and don't
have room for the full connector shell.

OP is designing a product, though (in quantity?). So if there is room for the shell, and a through-hole style connector is ok, I'd at least consider a HD
15-way D-sub. Cheap and effective.