Analyte monitoring device and methods

An apparatus for determining analyte concentration, comprising:

• an analyte sensor configured to have a portion in fluid contact with an interstitial fluid under a skin layer, the analyte sensor including a working electrode and a counter electrode;
• and
• an on-body electronics unit electrically coupled to the analyte sensor and comprising a housing with a plurality of electrical contacts, a first resistor-capacitor (RC) pair coupled between a first node and a second node, and a second RC pair coupled in series with the first RC pair between the second node and a third node,
• wherein:
• a first electrical contact of the plurality of electrical contacts of the on-body electronics unit is coupled to the first node, a second electrical contact of the plurality of electrical contacts of the on-body electronics unit is coupled to the second node, and a third electrical contact of the plurality of electrical contacts of the on-body electronics unit is coupled to the third node, and
• the first node is coupled to the working electrode and the third node is coupled to the counter electrode such that a first voltage between the first electrical contact and the second electrical contact of the on-body electronics unit represents a real-time current analyte concentration level, a second voltage between the second electrical contact and the third electrical contact of the on-body electronics unit represents an average analyte concentration level over a period of time, and a difference between the first voltage and the second voltage represents a real-time trending of the analyte concentration level.

A method of determining analyte concentration, comprising:

• generating a first voltage between a working electrode and a counter electrode of an analyte sensor, the analyte sensor being configured to have a portion in fluid contact with an interstitial fluid under a skin layer;
• and
• dividing the generated first voltage in an on-body electronics unit electrically coupled to the analyte sensor, the first voltage being divided between a first node, a second node, and a third node of the on-body electronics unit, the on-body electronics unit comprising a housing with a plurality of electrical contacts, a first resistor-capacitor (RC) pair coupled between the first node and the second node, and a second RC pair coupled in series with the first RC pair between the second node and the third node, the plurality of electrical contacts including a first electrical contact, a second electrical contact, and a third electrical contact;
• providing a second voltage between the first electrical contact and the second electrical contact, the first electrical contact being coupled to the first node, the second electrical contact being coupled to the second node;
• providing a third voltage between the second electrical contact and the third electrical contact, the third electrical contact being coupled to the third node,
• wherein the first node is coupled to the working electrode and the third node is coupled to the counter electrode such that the second voltage between the first electrical contact and the second electrical contact of the on-body electronics unit represents a real-time current analyte concentration level, the third voltage between the second electrical contact and the third electrical contact of the on-body electronics unit represents an average analyte concentration level over a period of time, and a difference between the second voltage and the third voltage represents a real-time trending of the analyte concentration level.