Zilog, Inc.

Ixys Ch Gmbh

Maxim Integrated Products, Inc.

Ixys Intl Limited

David R Staab

David D Eaton

Ruben C Zeta

Murray C Baker

A replaceable fluorescent lamp starter unit of a fluorescent light fixture has a built-in RF transceiver, and communicates wirelessly with a motion-detecting master unit. The starter unit can be controlled to turn off and turn on the fluorescent lamp of the fixture. The starter unit is registered to the master unit so that the starter unit will not respond to wireless communications from other sources. During registration, registration information is loaded into the starter unit and stored in non-volatile memory. The stored registration information is later usable to determine whether subsequently received wireless communications are for the starter unit. Systems of existing light fixtures are retrofitted with such wireless starter units, and thereby made controllable by a master unit so that the master unit can turn off the lights to conserve energy if room occupancy is not detected. The master unit can control lamp fixtures individually or as a group.

Registering a replaceable RF-enabled fluorescent lamp starter unit to a master unit

A lighting system includes a master that controls a plurality of light fixtures via wireless RF communications. An ambient light sensor in the master is used to monitor total ambient light and to prevent excessive illumination. In an auto-calibration process, the master makes ambient light measurements A, B and C when the light fixtures are illuminating an area at a minimum setting, at a maximum setting, and at an intermediate setting, respectively. A first threshold is set to be approximately (B&#x2212;A). A second threshold is set to be slightly larger than (B&#x2212;A)+(B&#x2212;C). In normal system operation, total ambient light measurements are taken and compared to the two thresholds. In one example, if detected brightness is lower than the first threshold then the system is set at its maximum illumination setting, whereas if detected brightness is greater than the second threshold then the system is set at its intermediate illumination setting.

Ambient light sensor auto-calibration in a lighting control system

A microcontroller integrated circuit includes an open-loop transimpedance amplifier (OLTA). An input lead of the OLTA is a terminal of the microcontroller. The cathode of a photodiode is connected to VDD and the anode is connected to the terminal. The OLTA maintains the photodiode in a strongly reverse-biased condition, thereby keeping diode capacitance low and facilitating rapid circuit response. The input of the OLTA involves a diode-connected field effect transistor that provides a low impedance. This low impedance decreases as the diode current increases, thus providing effective clamping of the voltage on the terminal. By this clamping, the amount of photodiode capacitance discharging necessary when transitioning from a high input current condition to a low input current condition is reduced, thereby further improving amplifier response time. The OLTA is small and consumes less than thirty microamperes and functions to mirror photodiode current and compare to a predetermined level.

Open-loop transimpedance amplifier for infrared diodes

A package-on-package (POP) secure module includes a BGA mesh cap, a first BGA package, and a second BGA package. The first BGA package includes a first integrated circuit (for example, a microcontroller that includes tamper detect logic). The second BGA package includes a second integrated circuit (for example, a memory). The second BGA package is piggy-back mounted to the first BGA package and the BGA mesh cap is piggy-back mounted to the second BGA package. A printed circuit board substrate member of the BGA mesh cap includes an embedded anti-tamper mesh. This mesh is connected in a protected manner within the module to the first integrated circuit. When the module is in use, a mesh embedded in an underlying printed circuit board is coupled to the BGA cap mesh so that both anti-tamper meshes are controlled by the tamper detect logic.

Package on-package secure module having BGA mesh cap

A microcontroller receives a supply voltage (VCC) from one or more batteries. Rather than automatically resetting the microcontroller if VCC drops below a VBO voltage, a latent VBO reset circuit does not reset the processor if VCC drops below a second voltage (VBO) as long as VCC does not fall so low that a power on reset (POR) circuit of the latent VBO reset circuit is tripped. The processor continues to operate as long as it can below VBO, thereby maximizing battery usage. When VCC rises to a third voltage (for example, due to battery replacement), then the latent VBO reset circuit automatically resets the processor to remove potential ill-effects of having operated below VBO. User data stored in volatile memory is not lost during battery replacement. A special VBO bit in a processor-readable status register indicates that the microcontroller operated below VBO.

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Los Gatos, CA, United States of America

David R Staab