Patent ID: 8450936

Claim:
A power supply for use with first and second input voltage ranges to provide power to first and second loads, each of said voltage ranges having a minimum voltage and a maximum voltage, the minimum voltage of said second input voltage range being greater than the maximum voltage of said first voltage range, said power supply comprising: a power input where an input voltage is applied; a threshold voltage detector responsive to the input voltage applied to said power input, said threshold voltage detector configured to detect a threshold voltage greater than said first voltage range maximum voltage and generate a threshold signal when exposed to said threshold voltage; a latch circuit responsive to a latch voltage less than said threshold voltage but greater than said first voltage range maximum voltage to maintain said threshold signal so long as said latch voltage is present; first and second current sources; and first and second electrical connections that change from a first state to a second state in response to said threshold signal, said first electrical contact connecting the first load and said first current source in said first state and connecting said first load in series with said second load in said second state, said second electrical contact connecting said input voltage to said second load in said first state and said input voltage to said latch circuit in said second state, wherein said first and second loads are connected between said input voltage and said first and second current sources, respectively, when said input voltage is less than said threshold voltage and said first and second loads are connected in series between said input voltage and said second current source when said input voltage is greater than said threshold voltage and said threshold signal is maintained and said first and second electrical connections remain in said second states so long as said input voltage is greater than said latch voltage.