[Ronja] Twister2 power problem

[Bruce M Simpson]

Bruce M Simpson wrote:
> I'm only seeing 0.82V on the output from the 2671M-5.0 (double checked 
> at U66 and other test points).
> I am using the National Semiconductor version of this part.
>
> The chip and the schottkys, caps etc appear to be in the correct place.
> What could be the problem? Interestingly I see around 6.3V on pin 5.
>   

I just looked at the LM2671 data sheet and I see that it seems to be 
very, very picky about the inductors which it needs.

I haven't, unfortunately, been able to obtain the exact parts in the 
Twister2 BoM here in the UK. I have mostly been sourcing parts through 
Farnell, however it looks like RS have a number of parts which they don't.

When I drive the 5V line directly from an external regulated supply, the 
Twister2 idle pulse and transmit functions normally (confirmed with the 
scope). So it looks like the silicon is OK. I haven't verified the 
receive path yet.

cheers
BMS