My current device design is using a 1W-6V solar panel to provide power input to a power management IC. I would like to to have the ability to utilize USB power OR the solar panel, not both. So if the USB source is providing power, the solar panel will stop providing power. Below is a screenshot of the circuit. Will this be sufficient or does the design need modified. Thanks.

 

So if the USB source is providing power, the solar panel will stop providing power.

No.take a look at the truth table for two input diode OR gate cuz that's what you have there.




Discrete OR gates may be realized by using diodes or transistors. The inputs represented as X and Y may be either 0V or +5V correspondingly. The output is represented by Z . In the diode of OR gate, when both the inputs are of same value, X=0V and Y= 0V, then both the diodes are in OFF condition. As a result, no current flows through the resistor and there will not be any voltage drop across the resistor. Here the output will be Z=0V. Similarly, when both the inputs or either the inputs such as X and Y are equal to +5V, then the corresponding diodes either D1 or D2 or both the diodes are at ON state and act as short circuits. Here the output will be Z corresponds to +5V. In practical cases the output Z corresponds to +5V-diode drop = +5V – 0.7V = +4.3V, which is regarded as Logic 1 state.