Abstract: An apparatus and method for determining the concentration of alcohol present in a gaseous mixture wherein an electronic device employing a fuel cell determines the concentration of alcohol present in the gaseous mixture is disclosed. In particular, the device may be used to determine a person's sobriety by determining the alcohol concentration in a breath sample. To determine the alcohol concentration, the device must be able to accurately determine the volume of breath in the breath sample. The device controls the volume of the breath sample by measuring the pressure of the breath flow through the device and, in response to the pressure, electronically controlling a valve diverting a portion of the breath flow into the fuel cell. One application of the invention is a sobriety interlock for a machine where the machine remains disabled unless the operator is first determined to have an alcohol concentration below a predetermined level.

Abstract: An apparatus and method for determining the concentration of alcohol present in a gaseous mixture wherein an electronic device employing a fuel cell determines the concentration of alcohol present in the gaseous mixture is disclosed. In particular, the device may be used to determine a person's sobriety by determining the alcohol concentration in a breath sample. To determine the alcohol concentration, the device must be able to accurately determine the volume of breath in the breath sample. The device controls the volume of the breath sample by measuring the pressure of the breath flow through the device and, in response to the pressure, electronically controlling a valve diverting a portion of the breath flow into the fuel cell thereby indicating and ensuring that a predefined requisite amount of breath flow has passed thru the fuel cell.

Abstract: A data bus controller is provided. The data bus controller comprises an ingress interface that receives single data streams of encoded data. A multiplexer is connected to the ingress interface and combines the single data streams into a broadcast data stream of encoded data. An egress interface connected to the multiplexer transmits the broadcast data stream. An arbiter is connected to the multiplexer. The arbiter generates control data for controlling the multiplexing of the single data streams and transmits control data to the multiplexer.