Apple Inc.

Noah M Price

Duane M Takahashi

R Stephen Polzin

David C Buuck

Laurence Alan Thompson

David H Titzler

Gary L Baker

A sensor is provided for automatically detecting the presence or absence of an electronic device which interfaces with other devices via an information signal. The sensor comprises a receiving connector which receives a mating connector associated with the electronic device to electrically and physically connect the device to the sensor and to another device. The receiving connector includes a terminal to which the information signal is applied. The sensor also comprises a sensing circuit connected to the terminal of the receiving connector for detecting whether the information signal is present at the terminal. The sensing circuit generates an output signal which indicates when a mating connector is received within the receiving connector, and thus whether the electronic device is present, in dependence upon whether the information signal is detected at the terminal. In one embodiment, the sensing circuit comprises a low-pass analog filter connected to a switching transistor for generating a signal at two logic levels. The two logic levels respectively indicate whether or not a mating connector is received within the receiving connector, and thus whether or not the electronic device is present.

Sensor for detecting the presence of a peripheral device

The clock configuration of a printed circuit board (PCB) processor card is described. A processor card including a processor, its associated processor card system bus, a clock generator, and its associated processor card system clock bus is optimized by providing various clock configurations and distributions. In one configuration, multiple clock signals are coupled to a system clock bus for distributing to a host card having system devices. In another configuration, multiple clock signals having various clock rates are coupled to the processor device on the processor card.

Clock distribution for processor and host cards

The present invention is a printed circuit board having conductive layers split into electrically isolated voltage supply plane regions each plane region being connectable to an external supply voltage. The voltage supply plane regions are split to reduce the total number of PCB conductive layers. Voltage supply plane regions are configured to match the device voltage requirements and their placement on the PCB. In the case in which a circuit includes a device having two voltage supply requirements, a first set of the device's power supply pins are fixedly coupled to a first voltage supply plane region and a second set of the device's power supply pins are fixedly coupled to a second voltage supply plane region. In this instance, each of the first and second voltage supply plane regions are fixedly connectable to external voltage supplies or to a voltage regulator according to the voltage supply requirements of the device.

Printed circuit board having split voltage planes

A computer system connector panel including EMI filtering on the computer system housing connector panel instead of on the system motherboard so that I/O signals are filtered just before being transmitted out of the computer system housing thereby reducing EMI affects on external A/V devices.

Connector interface including EMI filtering

A printed circuit board (PCB) processor card is described. The processor card includes a processor, its associated processor card system bus, a clock generator, and its associated processor card system clock bus. The processor card is designed to include the elements that are most likely to be upgraded, i.e. the processor and the clock. As such it is particularly useful when employed for system upgrades.

Printed circuit board processor card for upgrading a processor-based

A relatively inexpensive static random access memory is utilized to store persistent data in a computer. To provide the SRAM with this capability, it is connected to a source of power within the computer that includes a battery. The source of power is connected to the SRAM in a manner such that the SRAM is in an enabled state whenever any power is available to it, from either a battery or a power supply connected to a regulated voltage source. When the computer is turned off, to prevent devices connected to the SRAM from draining current being provided by the battery, a chip select terminal of the SRAM is isolated from other circuits on the computer, to prevent leakage.

Persistent data storage which utilizes a shared power supply

The present invention is a printed circuit board design having a configurable voltage supply and a method for implementing a configurable voltage supply PCB with a family of circuit designs. The printed circuit board is designed such that voltage supply planes can be configured to match the device requirements for different ICs inserted into the PCB. The PCB comprises electrically isolated conductive layers that are split into a plurality of electrically isolated fixed and undefined voltage planes. The fixed voltage planes are each coupled to a different supply voltage provided by an external power supply. Undefined voltage planes are coupled to fixed voltage planes with insertable conductive jumpers to obtain the desired voltage supply for each voltage plane. The voltage plane configuration of a particular PCB can be changed depending on where jumpers are inserted to accommodate device voltage requirements over a family of devices.

Growing community of inventors

Campbell, CA, United States of America

Noah M Price