Electron tunneling infrared sensor module with integrated control circuitry

• US 6,268,604 B1
• Filed: 03/02/1998
• Issued: 07/31/2001
• Est. Priority Date: 03/03/1997
• Status: Expired due to Fees

• Current Assignee: California Institute of Technology
• Original Assignee: California Institute of Technology
• Inventors: Boyadzhyan-Sevak, Vardkes V.
• Primary Examiner(s): Hannaher, Constantine
• Application Number:
  US09/033,353
• Time in Patent Office: 1,247 Days
• Field of Search: 250/338.1, 250/341.1, 600/316, 359/181
• US Class Current: 250/338.1
• CPC Class Codes: G01P 15/0894 by non-contact electron transfer, i.e. electron tunneling

Abstract

In an integrated electron tunneling sensor, an automatic tunneling control circuit varies a high voltage bias applied to the sensor deflection electrode in response to changes in sensor output to maintain the proper gap between the sensor tip and membrane. The control circuit ensures stable tunneling activity in the presence of large signals and other disturbances to the sensor. Output signals from the module may be derived from the amplified sensor output. The integrated sensor module is particularly well adapted for use in blood glucose measurement and monitoring system.

Claims

1. A sensor module comprising:

an electron tunneling sensor having a bias input and an output, the sensor producing an output signal in response to a proper bias condition in the sensor;

a control circuit having an input connected to receive said output signal and an output connected to provide a bias signal to said bias input;

the control circuit further comprising a feedback circuit which dynamically adjusts said bias signal in response to changes in said signal to re-balance said sensor to said proper bias condition;

a first amplifier having an input connected to said sensor and an output;

said control circuit further comprises an integrating amplifier having an input connected to said output of said first amplifier and an output connected to said bias input; and

an output buffer having an input connected to said output of said first amplifier and having a clamp for limiting to within a preselected range the magnitude of the output.