Hewlett-Packard Development Company, L.p.

Ser Chia Koh

Ning Ge

Leong Yap Chia

Wai Mun Wong

Chaw Sing Ho

John Oliver

In an example implementation, a method of operating a fluid sensing device includes enabling a fluid level sensing circuit on a printhead to determine a fluid level by sharing an applied charge between a capacitive sensor and a reference capacitor to determine a capacitance value of the capacitive sensor. The method includes enabling a fluid property sensing circuit on the printhead to determine a fluid property by measuring a transistor voltage that indicates a concentration of ions gathered on the capacitive sensor.

Semiconductor device including capacitive sensor and ion-sensitive transistor for determining level and ion-concentration of fluid

In one example, a printhead having an electrically-functional optical target. The printhead includes a substrate. An optical target having an optically-distinguishable shape and formed from at least one polysilicon strip is deposited on the substrate. An electrical connection to at least one of the polysilicon strips connect the strip into a circuit that is deposited on the substrate.

Electrically-functional optical target

A memory cell includes an input coupled to a read line, an output coupled to a circuit ground, a bi-polar memristor, and at least one address switch coupled to an address line to select the memory cell. A memory includes the bi-polar memristor and a one-way current conducting device, wherein the one-way current conducting device is positioned between the memristor cell output and the circuit ground, or between the read line and the memristor cell input.

Growing community of inventors

Singapore, Singapore

Ser Chia Koh