The advantages of using a digital DIP switch instead of a conventional
mechanical one is that the digital offers small size
and better security. The DS3904 is one example that contain
three digitally controlled nonvolatile (NV) variable resistors. It has the
capability to set the variable resistors into high-impedance state.
High impedance mode of DS3904 can be achieved by written the MSB of the selected resistor register to a ’1′. It is used to generate the High value when combined with a pullup resistor (as seen in the circuit diagram). To generate Low value, the resistor register must be set in position 0 to attain the smallest resistance available from the variable resistors (typically 400W).
By connecting a pullup resistor from each of the H terminal pins to a voltage potential, a HIGH state will be created when the corresponding variable resistor is placed in high-impedance mode (source: hqew.net)
and better security. The DS3904 is one example that contain
three digitally controlled nonvolatile (NV) variable resistors. It has the
capability to set the variable resistors into high-impedance state.High impedance mode of DS3904 can be achieved by written the MSB of the selected resistor register to a ’1′. It is used to generate the High value when combined with a pullup resistor (as seen in the circuit diagram). To generate Low value, the resistor register must be set in position 0 to attain the smallest resistance available from the variable resistors (typically 400W).
By connecting a pullup resistor from each of the H terminal pins to a voltage potential, a HIGH state will be created when the corresponding variable resistor is placed in high-impedance mode (source: hqew.net)
No comments:
Post a Comment