hi guys im want to switch a relay FRS1B-S, its a 5 volt relay
to swicht the relay i use a bc 550 npn transistor.
and i use the minibreakout board
my design is the same like this one
, except i changed the bc 547 to the bc 550
but if i set gpio 40 (J19 pin 10) to high it does not switch, although I mesure 1.8 volt on it.
root@ubilinux:/sys/class/gpio# echo 40 > export
root@ubilinux:/sys/class/gpio# cd gpio40
root@ubilinux:/sys/class/gpio/gpio40# echo out > direction
root@ubilinux:/sys/class/gpio/gpio40# echo 1 > value
if plug the cable from gpio 40 to J19 pin 2 which is also 1.8 volt and the transistor switch the relay. i have a drain from 500uA
on gpio40 is only a drain of 22 uA
can someone give me advice
bye stefan