System Considerations And Guidelines - Texas Instruments CC1020 Manual

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Figure 35. Typical PA_EN and LNA_EN pin drive
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System Considerations and Guidelines

SRD regulations
International regulations and national laws
regulate the use of radio receivers and
transmitters. SRDs (Short Range Devices)
for license free operation are allowed to
operate in the 433 and 868 - 870 MHz
bands in most European countries. In the
United States, such devices operate in the
260 - 470 and 902 - 928 MHz bands. A
summary of the most important aspects of
these regulations can
Application Note AN001 SRD regulations
for license free transceiver operation,
available from the TI web site.
Narrowband systems
CC1020
is specifically
narrowband systems complying with ARIB
STD T-67 and EN 300 220. The
meets the strict requirements to ACP
(Adjacent Channel Power) and occupied
bandwidth for a narrowband transmitter.
To meet the ARIB STD T-67 requirements
a 3.0 V regulated voltage supply should be
used.
For the receiver side,
good ACR (Adjacent Channel Rejection),
image frequency suppression and blocking
properties for channel spacings down to
12.5 kHz.
Voltage on PA_EN/LNA_EN pin [V]
source current, 3 V sink current, 3V
sink current, 2.3 V source current, 3.6 V
be found in
designed for
CC1020
CC1020
gives very
SWRS046B
source current, 2.3 V
sink current, 3.6 V
Such narrowband performance normally
requires the use of external ceramic filters.
CC1020
The provides this performance as
a true single-chip solution with integrated
IF filters.
Japan and Korea have allocated several
frequency bands at 424, 426, 429, 447,
449 and 469 MHz for narrowband license
CC1020
free operation.
meet the requirements for operation in all
these bands, including
requirements for narrowband operation
down to 12.5 kHz channel spacing.
Due to on-chip complex filtering, the image
frequency is removed.
calibration circuit is used to get the best
possible image rejection. A narrowband
preselector filter is not necessary to
achieve image rejection.
CC1020
A unique feature in
frequency resolution. This can be used for
temperature compensation of the crystal if
the temperature drift curve is known and a
temperature sensor is included in the
system. Even initial adjustment can be
performed using
programmability. This eliminates the need
for an expensive TCXO and trimming in
some applications. For more details refer
CC1020
is designed to
the strict
An on-chip
is the very fine
the frequency
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