Power supply redundancy circuit

A power routing circuit having first and second input nodes VIN1, VIN2 for connection to respective first and second power supplies and an output node VOUT1 for connection to a load, the power routing circuit comprising:

• a first main switching circuit connected between the first input node VIN1 and the output node VOUT1 and configured to conductively connect the first input node VIN1 to the output node VOUT1 if a voltage at the first input node VIN1 is higher than a voltage at the output node VOUT1, wherein the first main switching circuit includes an electronic switch controlled by a voltage comparator that compares the voltages at VIN1 and VOUT1;
• and
• a first auxiliary switching circuit connected between the second input node VIN2 and the output node VOUT1 and configured to conductively connect the second input node VIN2 to the output node VOUT1 if a voltage at the second input node VIN2 is higher than the voltage at the output node VOUT1 and the voltage at the first input node VIN1 is at least a threshold amount lower than the voltage at the second input node VIN2.