CHAPTER 2

Architecture

The internal modem is a separate module that contains the data pump IC and the interface to the telephone line (DAA). For more information about the modem, see “Internal Modem” (page 30).

Sound Circuitry

The sound circuitry, called Snapper, is connected to the Intrepid IC by a standard IIS (inter-IC sound) bus. The Intrepid IC provides DB-DMA (descriptor-based direct memory access) support for the IIS port.

Note: In the device tree, the sound circuitry is named “sound”.

The Snapper circuitry includes a signal processing IC that handles the equalization and volume control functions, a codec IC that performs A-to-D and D-to-A conversion, and a power amplifier that drives the headphone jack.

All audio is handled digitally inside the computer. The Snapper circuitry performs digital-to-analog conversion for the audio signals to the internal speakers and the headphone jack.

For a description of the features of the sound system, see “Sound System” (page 49).

Power Controller

The PowerBook G4 17-inch computer can operate from a 15 volt power outlet on an airline, but for safety reasons, the computer will not allow battery charging. In order for the computer to detect the connection to airline power, the airline power cable should have a sense resistor of 24.3 K ohms +/-1% connected between the power plug's shell and ground.

The PowerBook G4 17-inch computer has a variable speed fan control circuit and a thermal circuit that will force the unit into reduce-processor mode at 72 degrees Celsius and into sleep mode if the processor temperature exceeds 79 degrees Celsius.

The power management controller in the PowerBook G4 17-inch computer is a custom IC called the PMU99. It supports several power-saving modes of operation, including idle, doze, and sleep.

Note: In the device tree, the power controller is named “via-pmu”.

A device’s ID voltage limits determines how the PMU identifies the power adapter. The PowerBook G4 17-inch computer is designed to use the 65-Watt Apple Portable Power Adapter which ships with it. Although you can use a 45-Watt Apple portable power adapter with a 17-inch PowerBook G4 computer, it may not provide sufficient power during some activities and power may be drawn temporarily from the battery. Should the battery become discharged, you may need to plug in the 65-Watt Apple Portable Power Adapter that came with the computer in order to start it up.

AirPort Extreme Interface

AirPort Extreme contains a media access controller (MAC), a digital signal processor (DSP), and a radio-frequency (RF) section.

I/O Controller

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Legacy Document 2003-03-01 © 2003 Apple Computer, Inc. All Rights Reserved.

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Apple 17-INCH manual Sound Circuitry, Power Controller, AirPort Extreme Interface

17-INCH specifications

The Apple 17-inch model has garnered attention for its impressive balance of performance and portability, making it a popular choice among professionals and creative users alike. Boasting a sleek design, it combines cutting-edge technologies with user-friendly features that enhance productivity and entertainment experiences.

At the heart of the 17-inch display is Apple's Retina technology, which provides stunning visual clarity and vibrant colors. With a resolution that surpasses traditional screens, users can expect crisp text and detailed images, making it an ideal choice for graphic designers, video editors, and anyone who values high-quality visuals. The large screen size creates an immersive experience, especially useful for multitasking, viewing spreadsheets side by side, or editing documents side by side.

Powered by Appleā€™s latest custom silicon, the 17-inch model delivers remarkable performance. The optimizations in the chip architecture enhance not only processing speeds but also energy efficiency, allowing users to accomplish more without compromising battery life. These advancements in chip technology together with integrated graphics offer smooth performance during intensive tasks such as rendering high-definition graphics or playing demanding games.

The laptop also comes equipped with a robust battery system designed to keep users productive for extended periods. Users can expect several hours of usage on a single charge, ensuring that they can work or enjoy media without the constant need to recharge. Furthermore, fast-charging capabilities minimize downtime, making it convenient for on-the-go professionals.

In terms of connectivity, the 17-inch model offers multiple Thunderbolt and USB-C ports, allowing for quick data transfer and connecting a variety of external devices. This versatility is essential for professionals who may need to hook up to external monitors or utilize peripherals for enhanced functionality.

The built-in audio system features high-fidelity speakers, delivering an outstanding audio experience for music, movies, and video conferencing. The integration of advanced microphones further enhances clarity during calls, making communication seamless.

Overall, the Apple 17-inch laptop stands out as a powerful tool designed for those who demand performance, quality, and flexibility in their devices. With its blend of stunning visuals, powerful processing capabilities, and user-centric features, it remains a strong contender in the market for those seeking a reliable and stylish computing solution.