ATA5811-PLQX Atmel, ATA5811-PLQX Datasheet - Page 22

• Manufacturer Part Number: ATA5811-PLQX
• Manufacturer: Atmel

Specifications of ATA5811-PLQX

• Operating Temperature (min): -40C
• Operating Temperature (max): 105C
• Operating Temperature Classification: Industrial
• Product Depth (mm): 7mm
• Product Height (mm): 0.9mm
• Product Length (mm): 7mm
• Lead Free Status / Rohs Status: Compliant

XTO
22
ATA5811/ATA5812 [Preliminary]
.
Table 11. Impedance RF_OUT Pin in RX Mode
Note that if matching to 50 , like in Figure 5 on page 7, a high Q wire wound inductor
with a Q > 70 should be used for L
otherwise be dominant. The RX and TX losses will be in the range of 1.0 dB there.
The XTO is an amplitude regulated Pierce oscillator type with integrated load capaci-
tances (2
The XTO oscillation frequency f
synthesizer. When designing the system in terms of receiving and transmitting fre-
quency offset the accuracy of the crystal and XTO have to be considered.
The synthesizer can adjust the local oscillator frequency for more than ±150 ppm at
433.92 MHz/315 MHz and up to ±118 ppm at 868.3 MHz of initial frequency error in
f
and 3 (see Table 20 on page 35 and Table 23 on page 36). The remaining local oscilla-
tor tolerance at nominal supply voltage and temperature is then < ±0.5 ppm. A XTO
frequency error of ±150 ppm/±118 ppm can hence be tolerated due to the crystal toler-
ance at 25°C and the tolerances of C
less than ±2 ppm on the frequency at nominal supply voltage and temperature.
Over temperature and supply voltage, the XTO's additional pulling is only ±2 ppm if
C
quency error in the local oscillator.
The XTO frequency depends on XTAL properties and the load capacitances C
XTAL1 and XTAL2. The pulling of f
lowing formula:
C
XTAL found in its data sheet. C
circuit and consists of C
Figure 18. XTAL with Load Capacitance
P
XTO
m
m
=
is the crystal's motional, C
. This is done at nominal supply voltage and temperature with the control registers 2
7 fF. The XTAL versus temperature and its aging is then the main source of fre-
C
------- -
2
m
433.92
868.3
Frequency
315
-------------------------------------------------------------
C
18 pF with a tolerance of ±17%) hence C
0
MHz
MHz
+
MHz
C
C
L1
C
LN
LN
XTAL
–
C
C
L1
L
0
and C
+
C
L
0
L
XTO
the shunt and C
L2
C
is the total actual load capacitance of the crystal in the
10
L2
in series connection.
Z(RF_OUT)RX
XTO
2
is the reference frequency FREF for the fractional-N
36
19
2.8
6
to minimize its contribution to RX losses which will
L1
ppm.
from the nominal f
and C
j 502
j 366
j 141
L2
. The XTO’s gm has very low influence of
C
L
LN
Crystal equivalent circuit
= C
the nominal load capacitance of the
L
L1
m
Lmin
C
XTAL
L2
= 7.4 pF and C
C
C
/(C
m
0
L1
is calculated using the fol-
+ (C
R
7 k
7 k
7 k
m
L2
)
R
P
//C
1.0 pF
1.0 pF
1.3 pF
Lmax
P
4689B–RKE–04/04
= 10.6 pF.
L1, 2
at pin