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8-4 PXA250 and PXA210 Applications Processors Design Guide
Power and Clocking
8.4 Oscillator Electrical Specifications
The applications processor contains two oscillators – 32.768 kHz and 3.6864 MHz; each chosen
for a specific crystal. When choosing a crystal, match the crystal parameters as closely as possible.
8.4.1 32.768 kHz Oscillator Specifications
The 32.768 kHz Oscillator is connected between the TXTAL (amplifier input) and TEXTAL
(amplified output). The 32.768 kHz specifications are shown in Table 8-4.
P
VCCN_HB
@2.5V
Power from VCCN Supply, High Range (PXA250 applications
processor)
— 115 mW 250 mW
P
VCCN_HB
@3.3V
Power from VCCN Supply, High Range (PXA250 applications
processor)
— 160 mW 440 mW
PT_IDLE_H
Total Power, IDLE Mode, High Range — 135mW —
Peak Voltage Range (PXA250 applications processor only)
P
T_P
Total Power, Peak Range — 635 mW 950 mW
P
VCC_P
Power from VCC Supply, Peak Range — 470 mW 360 mW
P
VCCN_P
@2.5V
Power from VCCN Supply, Peak Range — 115 mW 255 mW
P
VCCN_P
@3.3V
Power from VCCN Supply, Peak Range — 160 mW 440 mW
PT_IDLE_H Total Power, IDLE Mode, High Range — 185mW —
NOTE: 1. These numbers are pre-silicon estimates, and will be replaced with the correct values when characterization is complete.
Table 8-3. Power Consumption Specifications (Sheet 2 of 2)
Symbol Description Min
1
Typical
1
Max
1
Table 8-4. 32.768 kHz Oscillator Specifications (Sheet 1 of 2)
Symbol Description Min Typical Max
Crystal Specifications - Typical is FOX NC38
F
XT
Crystal Frequency, TXTAL/TEXTAL — 32.768 kHz —
L
MT
Motional Inductance, TXTAL/TEXTAL — 6827.81 H —
C
MT
Motional Capacitance, TXTAL/TEXTAL — 3.455 fF —
R
MT
Motional Resistance, TXTAL/TEXTAL 6kΩ 16 kΩ 35 kΩ
C
OT
Shunt Capacitance TXTAL to TEXTAL — 1.6 pF —
C
LT
Load Capacitance TXTAL/TEXTAL — 12.5 pF —
Amplifier Specifications
V
IH_X
Input High Voltage, TXTAL 0.8 V*VCC — VCC
V
IL_X
Input Low Voltage, TXTAL VSS — 0.2 V*VCC
I
IN_XT
Input Leakage, TXTAL — — 1 µA
C
IN_XT
Input Capacitance, TXTAL/TEXTAL — 18 pF 25 pF