Implantable medical pump with multi-layer back-up memory
In a medical treatment device implanted within the body of a patient, a system and method using volatile and non-volatile memory devices within an implanted drug infusion pump to provide a safe and robust programmable system, able to back-up and restore the device's hardware and software operating parameters in the event of RAM corruption and as an alternative to hardware trim techniques. The pump includes a processor, a ROM, a RAM, and an EEPROM. The RAM serves as a main memory and the EEPROM serves a back-up memory in the event of RAM corruption. The ROM serves as an additional layer of back-up memory in the event of RAM and EEPROM corruption.
1. A method of updating trim parameter values for an integrated circuit within an implantable pump, comprising the steps of:
(a) receiving from an external programmer an updated trim parameter value corresponding to a trim parameter;
(b) validating the updated trim parameter value;
(c) copying the updated trim parameter value to a memory; and
(d) updating a hardware component associated with the trim parameter in accordance with the trim parameter value.
2. The method of updating trim parameter values of claim 1 , wherein the step of copying includes the step of copying the trim parameter value to a first memory and to a second memory.
3. The method of updating trim parameter values of claim 1 , further comprising the step of:
(e) if the trim parameter value is not valid, then issuing an error message to the external programmer.
4. A computer-readable medium having computer-executable instructions for performing the steps recited in claim 1 .
5. The method of updating trim parameter values of claim 1 , wherein the receiving of a parameter value in (a) comprises receiving a value for a parameter selected from the list consisting of a resistance value, a voltage reference and a bias current.
6. A method of updating trim parameter values for an integrated circuit within an implantable pump, comprising the steps of:
(a) receiving from an external programmer an updated trim parameter value corresponding to a trim parameter;
(b) validating the updated trim parameter value;
(c) copying the updated trim parameter value to a non-volatile programmable memory; and
(d) updating a hardware component associated with the trim parameter in accordance with the trim parameter value.
7. The method of claim 5 , wherein the copying to the non-volatile programmable memory in (c) comprises storing the parameter value in flash EEPROM.
8. The method of claim 5 , wherein the receiving of a parameter value in (a) comprises receiving a value for a parameter selected from the list consisting of a resistance value, a voltage reference and a bias current.