Bringing out internal Reference to an External pin in PSoC 3/5

Question: How do I route the internal reference to an external pin to bias my external circuit in PSoC 3/5?

 

Answer:

In PSoC 3/5, the user can bring out the internal reference to a pin for external biasing purposes. The 1.024 V reference is a direct connection to the 25mA buffer input. This makes it efficient to bring out the reference to the analog routing trough the buffer. The user could alternatively use a PGA of gain one to buffer the reference.

The internal reference is not strong enough to drive external loads. Hence it is recommended to buffer the reference before it is brought out on the external pin.

In PSoC Creator the internal reference can be accessed through the Vref component (under System Category). This Vref can be routed to the input of the Op-Amp buffer and the output of this Buffer can be further routed to an external pin. The user could alternatively use a PGA of gain one to buffer out the reference.