Matrix Orbital LCD0821 Legacy - Manual (Page 13)

LCD0821 rev 2 13
Note: The GPOs do not have any over current or over/under voltage protection so care must be taken when
using them. For instance if the external device is a relay it must be fully clamped (using a diode and
capacitor – see Figure 2-11) to absorb any generated back electro-motive force (EMF).
10 - 100 uF
1N400 1
Relay
coil
GPO
+ -
Figure 2-11 Clamping a Relay