SA-1110/Applications Processor Migration

A.1.3 Power Delivery

Although both products are tolerant to 3.3 V inputs and outputs, there is a difference in the supply voltage that drives the transistors of the microprocessor megacell. The PXA250 applications processor takes advantage of lower supply voltages to offer substantial power consumption savings. A design using SA-1110 has a supply voltage of 1.55 V to 1.75 V. The PXA250 applications processor is rated to 1.4 V maximum.

Drive the PXA250 applications processor core voltage pins at a lower voltage than the SA-1110 to reduce overall power consumption. The choice of voltage impacts the maximum upper frequency of operation so check the PXA250 documentation for the correct voltages as they are application dependent.

Also notice that the PXA250 applications processor supports independent power sources for Core, IO, Memory Bus, phase lock loops (PLLs), and a backup battery. It is recommended that these be independent power sources.

A.1.4 Package

The SA-1110 and the PXA250 applications processors are similar but not identical. The ball pitch of 1 mm is the same and the body outlines are both 17x17 mm but the heights are different. The PXA250 applications processor contains 4-layers within the package making it fractionally thicker than the SA-1110 2-layer package.

When migrating to the PXA210 applications processor there a few limits to functionality:

The upper 16-bits of the databus are unavailable

Only two of the primary GPIO pins are available

The upper two SDRAM bank strobes are unavailable

UART hardware flow control and external DMA are not accessible

This smaller package than the SA-1110 accommodates a lower overall power envelope that may restrict upper voltage operation and maximum frequency for power consumption reasons. The ball pitch is reduced to 0.8 mm and the package is much thinner than the mBGA.

A.1.5 Clocks

The crystal inputs for the PXA250 applications processor are at the same frequency as those for the SA-1110:

High frequency input of 3.6864 MHz

Slow real-time clock source of 32.768 KHz.

The input frequency requirements are relatively low, such that any crystal that is an AT-cut style with a certain amount of shunt capacitance will work for both products.

The actual PLL design and process technology is different between the two products, such that a marginal SA-1110 design may not work with the PXA250 applications processor. Please refer to the product specifications of each device for further details.

A-4

PXA250 and PXA210 Applications Processors Design Guide

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Intel PXA250 and PXA210 manual Power Delivery, Package, Clocks

PXA250 and PXA210 specifications

The Intel PXA250 and PXA210 processors, part of the Intel XScale architecture, were introduced in the early 2000s, targeting mobile and embedded applications. They are known for their low power consumption, high performance, and advanced multimedia capabilities, making them suitable for a wide range of devices, including PDAs, smartphones, and other portable computing devices.

The PXA250, which operates at clock speeds ranging from 400 MHz to 624 MHz, features a superscalar architecture that allows it to issue multiple instructions per clock cycle. This enhances the overall performance for demanding applications while maintaining low power usage. It supports a variety of peripheral interfaces, including USB, Ethernet, and various memory types, which contributes to its versatility in different product designs.

One of the key technologies in the PXA250 is the integrated Intel Smart Repeat Technology, which optimizes data processing, thereby reducing the amount of power consumed during operation. This feature is particularly important for battery-powered devices, as it extends the overall battery life, allowing for longer usage times in mobile environments. Additionally, the PXA250 includes a dedicated graphics acceleration unit, which enables enhanced graphics and multimedia performance suited to modern applications at the time.

In contrast, the PXA210 is a more entry-level processor, aimed at cost-sensitive applications. Operating at lower clock speeds, typically around 200 MHz to 400 MHz, it forgoes some of the advanced performance features of the PXA250 while still offering a good balance of performance and power efficiency. The PXA210 is less complex, making it suitable for simpler devices that do not require the extensive capabilities of the PXA250.

Both processors utilize the Intel XScale architecture, which is based on the ARM instruction set. They are built on a 0.13-micron process technology, enabling higher density and lower power consumption compared to their predecessors. With integrated memory controllers and bus interfaces, they facilitate efficient data handling and connectivity options.

In summary, both the Intel PXA250 and PXA210 processors played a crucial role in the evolution of mobile computing by providing powerful processing capabilities with energy efficiency. Their features and technologies enabled device manufacturers to create innovative products that catered to the growing demand for portable devices during that era.