Power and Clocking

Table 8-6. PXA250 and PXA210 VCCN vs. VCCQ (Sheet 6 of 6)

Pin

Pin

Alt_fn

Alt_fn

Alt_fn

Alt_fn

Signal Description and

Power

Count

1-(in)

2-(in)

1-(out)

2-(out)

Comments

Supply

 

 

 

 

 

 

 

 

 

GP73

1

 

 

 

LDD[15]

LCD data pin 15

VCCQ

 

 

 

 

 

 

 

MBGNT

 

memory controller grant

 

 

 

 

 

 

 

 

 

 

 

 

 

 

GP74

1

 

 

 

LCD_FCL

LCD Frame clock

VCCQ

 

 

 

 

 

K

 

 

 

 

 

 

 

 

 

 

GP75

1

 

 

 

LCD_LCL

LCD line clock

VCCQ

 

 

 

 

 

K

 

 

 

 

 

 

 

 

 

 

GP76

1

 

 

 

LCD_PCL

LCD Pixel clock

VCCQ

 

 

 

 

 

K

 

 

 

 

 

 

 

 

 

 

GP77

1

 

 

 

LCD_AC

LCD AC Bias

VCCQ

 

 

 

BIAS

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

PXTAL

1

 

 

 

 

3.6Mhz Crystal input

0.8 * VCC

 

 

 

 

 

 

 

 

PEXTAL

1

 

 

 

 

3.6Mhz Crystal output

0.8 * VCC

 

 

 

 

 

 

 

 

TXTAL

1

 

 

 

 

32khz Crystal input

0.8 * VCC

 

 

 

 

 

 

 

 

TEXTAL

1

 

 

 

 

32khz Crystal output

0.8 * VCC

 

 

 

 

 

 

 

 

8.5.2Power On Timing

The External Voltage Regulator and other power-on devices must provide the applications processor with a specific sequence of power and resets to ensure proper operation. This sequence is shown in Figure 8-1,“Power-On Reset Timing” on page 8-12and detailed in Table 8-7, “Power- On Timing Specifications” on page 8-12.

It is important that the applications processor power supplies be powered-up in a certain order to avoid high current situations. The required order is:

1.VCCQ

2.VCCN

3.VCC and PLL_VCC

VCCN may be powered at the same time as VCCQ, however do not apply power to VCCN before powering VCCQ.

PXA250 and PXA210 Applications Processors Design Guide

8-11

Page 79
Image 79
Intel manual Power On Timing, PXA250 and PXA210 Vccn vs. Vccq Sheet 6

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.