ATSAM2133B ATMEL Corporation, ATSAM2133B Datasheet - Page 12

• Manufacturer Part Number: ATSAM2133B
• Description: Low-power Synthesizer
• Manufacturer: ATMEL Corporation

Timings
Crystal Frequency
Selection
12
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ATSAM2133B
All timing conditions: V
load capacitance = 30 pF.
All timings refer to t
The internal master clock frequency is four times the frequency at pin X1. Therefore t
= t
The sampling rate is given by 1/(t
quency at X1 is 12.288 MHz (48 kHz sampling rate).
There is a trade-off between the crystal frequency and the support of widely-available
external ROM/Flash components. Table 8 gives information on selecting the best fit for
a given application.
Table 8. Crystal Frequency Selection Parameters
Using 11.2896 MHz crystal frequency allows the use of widely-available ROMs with 100
ns access time while providing state-of-the-art 44.1 kHz sampling rate.
Sample Rate (KHz)
XTAL
/4.
31.25
44.1
37.5
48
CK
, the internal master clock period.
11.2896
Crystal
12.288
C2
(MHz)
9.60
8.00
= 2.5V, V
20.35
22.14
26.04
31.25
(ns)
CK
t
CK
C3
x 1024). The maximum crystal frequency/clock fre-
= 3.3V, t
ROM t
(ns)
101
120
146
92
A
A
= 25°C, all outputs except X2 and LFT
Comments
Maximum frequency
Recommended for current designs
2694A–DRMSD–05/03
CK