xe1205 Semtech Corporation, xe1205 Datasheet - Page 36

• Manufacturer Part Number: xe1205
• Description: Low-power, High Link Budget Integrated Uhf Transceiver
• Manufacturer: Semtech Corporation

The XE1205 has four main operating modes illustrated in Table 26 below. These modes are defined by register
MCParam_Chip_mode(1:0) when bit MCParam_Select_mode is low and defined by SW(1:0) pins when
MCParam_Select_mode is high. Please note that in both cases the changes will be applied to the transceiver upon the
rising edge of the NSS_CONFIG signal (ie NSS_CONFIG must be set low even when using SW(1:0) as inputs).
MCParam_Select_mode
0
0
0
0
1
1
1
1
7.3.1
The transceiver is able to switch between modes by using the SPI_CONFIG interface.(MCParam_Chip_mode(1:0)) or by
using the pin SW(1:0). This section describes the switching sequence of the transceiver when register
MCParam_Select_mode is low i.e. the configuration is done via the SPI_CONFIG and SW(1:0) is an output.
The sequence from sleep mode to receive mode via stand-by mode is shown in Figure 19Error! Reference source not
found. TS_SRE is the receiver wake-up time when the oscillator is enabled, defined as the initialization time for the
frequency synthesizer and the base band filter. The base band filter initialization and calibration processes occur when
the transceiver switches from stand-by to receive.
The sequence from sleep to transmit mode via stand-by mode is displayed in Figure 20. TS_STR is the initialization
time of the frequency synthesizer and the power amplifier.
© Semtech 2007
7.3
Programmed mode
NSS_CONFIG
Actual mode
XE1205 switching time using SPI_CONFIG interface.
OPERATING MODES
Figure 19 Sequence from sleep mode to receive mode via standby mode.
MCParam_Chip_mode(1:0)
00
01
10
11
00
01
10
11
Sleep
Sleep
Table 26: Operating modes
TS_OS
SW(1:0)
mode
Output
Output
Output
Output
Input
Input
Input
Input
36
Stand-by
Stand-by
SW(1:0)
value
00
01
10
11
00
01
10
11
Operating
Mode
Sleep
Receive
Transmit
Standby
Sleep
Receive
Transmit
Standby
TS_SRE
Receive
Receive
Enabled blocks of the
transceiver
-
Quartz oscillator, Frequency
synthesizer, Receiver
Quartz oscillator, Frequency
synthesizer, Transmitter
Quartz oscillator
-
Quartz oscillator, Frequency
synthesizer, Receiver
Quartz oscillator, Frequency
synthesizer, Transmitter
Quartz oscillator
XE1205
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