Power Management Board

Electronics
1

Hello, I am ordering the power mangement board. But there is a component, R5 which has no value.
It says value 0. Can anyone tell me what the resistor has to be?

2

Hi,

This resistor R5 is 0 Ohm (short circuit). It is in series with the mosfet gate. It is common practice in prototype phase to have 0ohm to later take measurement, or insert a small current limiting resistor.

Please note that this board is still not considered totally validated. Mainly, we have had problem with non stm32f103 chip that are out of stock from official reseller. With the fake STM32, the problem was with SPI in slave mode. I won’t advise assembling a board without being sure to get a genuine stm32.

The situation is so bad with STM32 that I’m considering redesigning the board with a ESP32, but I can not give a timeline for now.

1 Like
3

thank you for your reply.

4

Hello,
maybe you can also tell me which diode I need for D3. the comment says Diode_SMD:D_0402_1005Metric
There are a lot of possibilities.
thanks

5

Any signal diode will work. It will be working with low voltage and low current.
You just need to find one that fit to 0402 footprints.

You can share your choice here if you manage to find something in stock. I can validate it for you.

1 Like
6

Hello, thanks. Is this a good one?
NSR05F40NXT5G

7

Hi,

Yes, this one will work just fine.

In the later revision, I might use a more standard footprint to have more option.

1 Like
8

thank you, the only problem is to find:

U2 INA239 VSSOP-10_3x3mm_P0.5mm
U3 MAX17501BxTB TDFN-10-1EP_2x3mm_P0.5mm_EP0.9x2mm

They cannot be delivered until begin 2023.
Is there anyone who knows how to get hold of these components?