Handheld medical device functionality without battery

1. A handheld diabetes management device that is at least partially functional while a battery of the handheld diabetes management device is discharged and power is supplied to the handheld diabetes management device via a universal serial bus (USB) connection, the handheld diabetes management device comprising:

a housing having a blood glucose (bG) test strip port;

a processor module carried in the housing, the processor module including memory having instructions for executing functions of the handheld diabetes management device and a processor configured for executing the instructions;

battery terminals that electrically connected the processor module:

a re-chargeable battery electrically connected to the battery terminals;

a bG measurement engine coupled to the processor and the re-chargeable battery, the bG measurement engine configured to measure a bG level;

a receptacle that is configured in accordance with a universal serial bus (USB) standard;

a plug that is configured in accordance with the USB standard;

at least one component for communicating information from the handheld diabetes management device to one of a user and another device; and

a multiplexer module that receives power via the receptacle from the plug and prevents the measurement of the bG level,

a bus voltage node that selectively received power from the multiplexer module,

wherein the processor module is configured to directly connect to the bus voltage node and the processor module receives power from the bus voltage node based upon the re-chargeable battery being discharged,

wherein the at least one component receives power via the bus voltage node based upon the re-chargeable battery being discharged, and

wherein the processor module is configured to control application of power to the at least one component and operation of the at least one component based upon the re-chargeable battery is discharged.

2. The diabetes management device of claim 1 wherein the multiplexer module includes a switching device that is connected between the receptacle and the bus voltage node, and

wherein the switching device is open circuited when the power output to the bus voltage node is greater than a predetermined value.

3. The handheld diabetes management device of claim 1 further comprising,

a switching device; and

a second voltage node that is connected between the switching device and the bus voltage node, with the at least one component receiving power from the second voltage node.

4. The handheld diabetes management device of claim 3 wherein the processor module closes the switching device based upon determination that the re-chargeable battery is not connected to the battery terminals.

5. The handheld diabetes management device of claim 3 further comprising a diode that is connected between the switching device and the second voltage node, that allows current flow from the switching device to the second voltage node, and that blocks current flow from the second voltage node to the switching device.

6. The handheld diabetes management device of claim 3 further comprising,

a second switching device that is connected between the bus voltage node; and

a third voltage node connected to the second switching device, the bus voltage node, one of the battery terminals, and the processor module.

7. The handheld diabetes management device of claim 6 further comprising:

a blood glucose (bG) test strip port; and

a bG measurement engine that is connected to the third voltage node and that measures a bG level;

a bG test strip,

wherein the at least one component includes a communication module that communicates data from the handheld diabetes management to another device.

8. The handheld diabetes management device of claim 7 wherein:

the re-chargeable battery is connected to the battery terminals and the processor module is configured to open and close the switching device and the second switching device; and

the re-chargeable battery is not connected to the battery terminals and; the processor module is configured to open and close the switching device and the second switching device.

9. The handheld diabetes management device of claim 8 wherein:

the re-chargeable battery is connected to the battery terminals and; the processor module is configured to opens the switching device and closes the second switching device; and

the re-chargeable battery is not connected to the battery terminals and the processor module is configured to close the switching device and opens the second switching device.

10. The handheld diabetes management device of claim 1 further comprising:

a first current path from the re-chargeable battery to the processor module; and

a second current path from the receptacle to the processor module via the multiplexer module and the bus voltage node,

wherein, when the re-chargeable battery is not connected to the battery terminals, the processor module receives power via the second current path.

11. The handheld diabetes management device of claim 1 further comprising:

a first current path from the re-chargeable battery to the at least one component; and

a second current path from the bus voltage node to the at least one component.

12. The handheld diabetes management device of claim 11 wherein:

the processor module is configured to enable current flow through the first current path and disables current flow through the second current path based on a determination that the re-chargeable battery is connected to the battery terminals; and

the processor module is configured to disable current flow through the first current path and enables current flow through the second current path based on a determination that the re-chargeable battery is not connected to the battery terminals.

13. The handheld diabetes management device of claim 1 wherein the at least one component includes a touchscreen display, a backlight of the touchscreen display, a visual indicator, and a vibrator device.