NXP Semiconductors MKW01Z128, Reference Manual, Page: 82 / 884

Transceiver Operating Modes
MKW01xxRM Reference Manual, Rev. 3, 04/2016
Freescale Semiconductor, Inc. 6-3
• In Packet mode - the transmitter will automatically modulate the RF signal with preamble bytes as
soon as
TxReady or ModeReady happen. The actual packet transmission (starting with the number
of preambles specified in PreambleSize ) will start when the TxStartCondition is fulfilled.
6.2.3 Receiver Startup Time
It is highly recommended to use the built-in sequencer of the transceiver to optimize the delays when
setting the chip in receive mode. It guarantees the shortest startup times, hence the lowest possible energy
usage, for battery operated systems.
The startup times of the receiver can be calculated from the following:
Figure 6-2. RX Startup - No AGC, no AFC
Figure 6-3. RX Startup - AGC, no AFC
Figure 6-4. RX Startup - AGC and AFC
The different timings shown above are as follows:
• Group delay of the analog front end - Tana = 20 us
• Channel filter’s group delay in FSK mode - Tcf = 21 / (4 * RxBw)
• Channel filter’s group delay in OOK mode - Tcf = 34 / (4 * RxBw)
Analog FE’s
group delay
Channel Filter’s
group delay
DC Cutoff’s
group delay
RSSI
sampling
XO Started and PLL is locked
Tana
RSSI
sampling
Tcf Tdcc Trssi Trssi
Reception of Packet
ModeReady
RxReady
TS_RE
Rx startup request
( sequencer or user )
Analog FE’s
group delay
Channel Filter’s
group delay
DC Cutoff’s
group delay RSSI
sampling
XO Started and PLL is locked
Tana
RSSI
sampling
Tcf Tdcc Trssi Trssi
Reception of Packet
ModeReady
RxReady
Channel Filter’s
group delay
DC Cutoff’s
group delay RSSI
sampling
Tcf Tdcc Trssi
The LNA gain is adjusted by
the AGC, according to the
RSSI result
TS_RE_ AGC
Rx startup request
( sequencer or user )
Analog FE’s
group delay
Channel Filter’s
group delay
DC Cutoff’s
group delay RSSI
sampling
XO Started and
PLL is locked
Tana
RSSI
sampling
Tcf Tdcc Trssi Trssi
Reception of Packet
ModeReady
RxReady
Channel Filter’s
group delay
DC Cutoff’s
group delay RSSI
sampling
Tcf Tdcc Trssi
AFC
Tafc
PLL
lock
Tpllafc
Channel Filter’s
group delay
Tcf
DC Cutoff’s
group delay
Tdcc
TS_RE_ AGC& AFC
Rx startup request
( sequencer or user )
The LNA gain is adjusted by
the AGC, according to the
RSSI result
Carrier Frequency is adjusted
by the AFC