ata5756-6dqy ATMEL Corporation, ata5756-6dqy Datasheet - Page 8

• Manufacturer Part Number: ata5756-6dqy
• Description: Ata5756 Uhf Ask/fsk Transmitter
• Manufacturer: ATMEL Corporation

4.3
8
Accuracy of Frequency Deviation
ATA5756/ATA5757
Figure 4-4.
The accuracy of the frequency deviation using the XTAL pulling method is about 20% if the fol-
lowing tolerances are considered. One important aspect is that the values of C
crystals are strongly correlated which reduces the tolerance of the frequency deviation.
Figure 4-5.
Using a crystal with a motional capacitance of C
C
C
internal FSK switch with C
the resulting C
deviation of ±19.3 kHz with worst case tolerances of ±15.8 kHz to ±23.2 kHz.
0
LNOM
= 297
ENABLE
= 18 pF and a parallel capacitance of C
FSK
ASK
CLK
C
M
4
Timing ASK Mode with ENABLE Connected to the Microcontroller
Tolerances of Frequency Modulation
and C
the correlation has a tolerance of 10%, so C
XTAL
Power-down
V
S
5
~
values are C
Switch
= 0.9 pF ±20% and estimated parasites of C
T
XTO
4
Power-up,
= 10 pF ±1% and C
PA off
Crystal equivalent circuit
C
> 250 µs
M
L
M
C
M
0
= 4.37 fF ±15%, a nominal load capacitance of
Power-up,
0
= 1.30 pF correlated with C
PA on
(High)
R
S
5
= 15 pF ±1% for a nominal frequency
0
Power-up,
= 267 to 326
PA off
(Low)
C
Stray
C
5
C
Switch
C
Stray
4
Power-down
0
and C
C
= 0.7 pF ±10%,
M
). If using the
4702I–RKE–11/05
M
M
results in
of typical