RFM69W Datasheet, PDF (37/78 Pages) List of Unclassifed Manufacturers – ISM TRANSCEIVER MODULE

RFM69W
Rx startup request
(sequencer or user)
TS_RE
XO Started and PLL is locked
ModeReady
RxReady
Analog FE’s
group delay
Tana
Channel Filter’s
group delay
Tcf
DC Cutoff’s RSSI
RSSI
group delay sampling sampling
Tdcc
Trssi
Trssi
Reception of Packet
Received Packet Preamble may start
Figure 18. Rx Startup - No AGC, no AFC
Rx startup request
(sequencer or user)
TS_RE_AGC
The LNA gain is adjusted by
the AGC, according to the
RSSI result
XO Started and PLL is locked
ModeReady
Analog FE’s
group delay
Tana
Channel Filter’s
group delay
Tcf
DC Cutoff’s RSSI
RSSI
group delay sampling sampling
Channel Filter’s
group delay
Tdcc
Trssi
Trssi
Tcf
DC Cutoff’s RSSI
group delay sampling
Reception of Packet
Tdcc
Trssi
RxReady
Received Packet Preamble may start
Figure 19. Rx Startup - AGC, no AFC
Rx startup request
(sequencer or user)
TS_RE_AGC&AFC
The LNA gain is adjusted by
the AGC, according to the
RSSI result
Carrier Frequency is adjusted
by the AFC
XO Started and Analog FE’s Channel Filter’s DC Cutoff’s RSSI
RSSI Channel Filter’s DC Cutoff’s RSSI
PLL is locked group delay group delay group delay sampling sampling group delay group delay sampling
AFC
PLL
lock
Channel Filter’s
group delay
DC Cutoff’s
group delay
Reception of Packet
ModeReady
Tana
Tcf
Tdcc
Trssi
Trssi
Tcf
Tdcc
Trssi Tafc Tpllafc
Tcf
Tdcc
RxReady
Received Packet Preamble may start
Figure 20. 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)
‹ DC Cutoff’s group delay:
Tdcc = max(8 , 2^(round(log2(8.RxBw.Tbit)+1)) / (4.RxBw)
‹ PLL lock time after AFC adjustment:
Tpllafc = 5 / PLLBW (PLLBW = 300 kHz)
‹ AFC sample time:
Tafc = 4 x Tbit
(also denoted TS_AFC in the general specification)
‹ RSSI sample time:
Trssi = 2 x int(4.RxBw.Tbit)/(4.RxBw) (aka TS_RSSI)
Note The above timings represent maximum settling times, and shorter settling times may be observed in real cases
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