ATA8202-EK Atmel, ATA8202-EK Datasheet - Page 16

• Manufacturer Part Number: ATA8202-EK
• Description: BOARD RF RCVR FLEXIBLE 433MHZ
• Manufacturer: Atmel
• Type: Receiver, ASK/FSKr

Specifications of ATA8202-EK

• Frequency: 433MHz ~ 435MHz
• For Use With/related Products: ATA8202
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

16
ATA8201/ATA8202
With C
P ±1 ppm.
The C
not enter the steep region of pulling versus load capacitance where there is risk of an unstable
oscillation.
To ensure proper start-up behavior, the small signal gain and the negative resistance provided
by this XTO at start is very large. For example, oscillation starts up even in the worst case with a
crystal series resistance of 1.5 k at C
approximately given by
with Z
Z
Z
Z
XTAL2, with typically 20 mS at 25°C.
With f
tance of about 2 k . The worst case for technology, supply voltage, and temperature variations
is then always higher than 1.4 k for C
Due to the large gain at start, the XTO is able to meet a very low start-up time. The oscillation
start-up time can be estimated with the time constant .
After 10 to 20
High if the amplitude is large enough; this activates the CLK_OUT output if it is enabled via the
pins CLK_OUT_CTRL0 and CLK_OUT_CTRL1. Note that the necessary conditions of the
DVCC voltage also have to be fulfilled.
It is recommended to use a crystal with C
C
Lower values of C
higher values of C
Re Zxtocore
1
3
3
0
=
= –j / (2
consists of crystal C
= –j / (2
= 1.0 pF to 2.2 pF.
------------------------------------------------------------------------------------------------------------------ -
4
XTO
1
0
and Z
m
of the XTAL has to be lower than C
2
= 13.5 MHz, gm = 20 mS, C
10 fF, C
f
=
2
p
XTAL
p
as complex impedances at pins XTAL1 and XTAL2, hence
Re
2
f
f
XTO
XTO
m
an amplitude detector detects the oscillation amplitude and sets XTO_OK to
m
Z
---------------------------------------------------------------------------------------- -
0
(up to 15 fF) can also be used, with only little influence on pulling.
1
C
can be used, slightly increasing the start-up time. Lower values of C
Z
m
1
0
2
Z
1.0 pF, C
+
C
C
in parallel with an internal 110-k resistor, hence
3
Z
L1
0
+
) / 110 k , gm is the internal transconductance between XTAL1 and
Re Z
2
) + 5 and Z
Z
+
2
Z
3
xtocore
Z
+
LN
3
Z
+
1
= 9 pF and C
Z
L
+
1
0
Z
= 9 pF, and C
R
2
2
0
m
= –j / (2
Z
2.2 pF.
Lmin
3
gm
2.2 pF with this XTO. The negative resistance is
m
gm
/ 2 = 7.9 pF for a Pierce oscillator type in order to
= 3.0 fF to 10 fF, C
L1,2
p
0
= 2.2 pF, this results in a negative resis-
= 16 pF ±1%, the pulling amounts to
f
XTO
C
L2
) + 5 .
LN
= 9 pF, R
4971C–INDCO–04/09
m
< 120
and
0
or