Power and Clocking

Table 8-4. 32.768 kHz Oscillator Specifications (Sheet 2 of 2)

Symbol

Description

Min

Typical

Max

 

 

 

 

 

tS_XT

Stabilization Time

2 s

10 s

Board Specifications

 

 

 

 

 

 

 

 

RP_XT

Parasitic Resistance, TXTAL/TEXTAL to any node

20 M

CP_XT

Parasitic Capacitance, TXTAL/TEXTAL, total

5 pF

COP_XT

Parasitic Shunt Capacitance, TXTAL to TEXTAL

0.4 pF

To drive the 32.768 kHz crystal pins from an external source:

Drive the TEXTAL pin with a digital signal that has a low level near 0 V and a high level near VCC. Do not exceed VCC or go below VSS by more than 100 mV. The minimum slew rate is 1V per s. The maximum current drawn by the external clock source when the clock is at its maximum positive voltage should be about 1mA.

Float the TXTAL pin or drive it complementary to the TEXTAL pin, using the same voltage level, slew rate, and input current restrictions.

8.4.23.6864 MHz Oscillator Specifications

The 3.6864 MHz Oscillator is connected between the PXTAL (amplifier input) and PEXTAL (amplified output). The 3.6864 MHz specifications are shown in Table 8-5

Table 8-5. 3.6864 MHz Oscillator Specifications

Symbol

Description

Min

Typical

Max

 

 

 

 

 

 

Crystal Specifications - Typical is FOX HC49S

 

 

 

 

 

 

 

 

 

 

FXP

Crystal Frequency, PXTAL/PEXTAL

 

3.6864 MHz

LMP

Motional Inductance, PXTAL/PEXTAL

 

0.50593 H

CMP

Motional Capacitance, PXTAL/PEXTAL

 

3.68488 fF

RMP

Motional Resistance, PXTAL/PEXTAL

50

99.3

200

COP

Shunt Capacitance PXTAL to PEXTAL

 

1.7 pF

CLP

Load Capacitance PXTAL/PEXTAL

 

20 pF

Amplifier Specifications

 

 

 

 

 

 

 

 

 

VIH_X

Input High Voltage, PXTAL

0.8V*VCC

VCC

VIL_X

Input Low Voltage, PXTAL

VSS

0.2 V*VCC

IIN_XP

Input Leakage, PXTAL

 

10 A

CIN_XP

Input Capacitance, PXTAL/PEXTAL

 

40 pF

50 pF

tS_XP

Stabilization Time

17.8 ms

67.8 ms

Board Specifications

 

 

 

 

 

 

 

 

 

RP_XP

Parasitic Resistance, PXTAL/PEXTAL to any node

20 M

CP_XP

Parasitic Capacitance, PXTAL/PEXTAL, total

 

5 pF

COP_XP

Parasitic Shunt Capacitance, PXTAL to PEXTAL

 

0.4 pF

To drive the 3.6864 MHz crystal pins from an external source:

PXA250 and PXA210 Applications Processors Design Guide

8-5

Page 73
Image 73
Intel PXA250 and PXA210 manual 2 3.6864 MHz Oscillator Specifications, kHz Oscillator Specifications Sheet 2

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.