3.9.17.4 SSMFBR – SSM Filter Bandwidth Register

Several options can be selected to control and optimize the settling wait times depending on the filter bandwidth chosen.

Name:	SSMFBR
Offset:	0x0E4
Reset:	0x00


Bit	7	6	5	4	3	2	1	0
			SSMPLDT	SSMHADT	SSMDFDT	SSMFID[2:0]
Access	R	R	R/W	R/W	R/W	R/W	R/W	R/W
Reset	0	0	0	0	0	0	0	0

Bit 7 – Reserved Bit

This bit is reserved and read as ‘0’.

Bit 6 – Reserved Bit

This bit is reserved and read as ‘0’.

Bit 5 – SSMPLDT Sequencer State Machine PLL Lock Delay Time

0 = 13 μs delay time in the PLL lock state machine

1 = 63 μs delay time in the PLL lock state machine The longer setting (SSMPLDT = 1) has to be used if the filter bandwidth is less than 125 kHz.

Bit 4 – SSMHADT Sequencer State Machine Half Antenna Damping Delay Time

Writing a ‘1’ to this bit halves the channel filter delay time in the antenna damping sequence of the get telegram state machine.

Bit 3 – SSMDFDT Sequencer State Machine Double Filter Delay Time

Writing a ‘1’ to this bit doubles the channel filter delay time in the RX DSP enable state machine and in the antenna damping sequence of the get telegram state machine.

Bits 2:0 – SSMFID[2:0] Sequencer State Machine Filter Delay

This value defines the general channel filter delay times for the SSM after enabling the channel filter or switching the antenna damping. If the used bandwidth is not in the table, the next smaller bandwidth value (longer delay time) must be used. The following table shows the resulting delay times in the RX DSP enable and the get telegram state machine depending on the three SSMFID, SSMDFDT and SSMHADT settings.

Table 3-62. SSMFIB Filter Bandwidth Settings
SSMFID	Delay Time in RX DSP Enable		Delay Time in Antenna Damping			Bandwidth of Channel Filter
	SSMDFDT = 0	SSMDFDT = 1	SSMDFDT = SSMHADT	SSMDFDT = 0 SSMHADT = 1	SSMDFDT = 1 SSMHADT = 0
0x0	380 µs	760 µs	380 µs	190 µs	760 µs	25 kHz
0x1	202.µs	405 µs	202.5 µs	101.25 µs	405 µs	50 kHz
0x2	135 µs	270 µs	135 µs	62.5 µs	270 µs	80 kHz
0x3	75 µs	150 µs	75 µs	37.5 µs	150 µs	165 kHz
0x4	58.5 µs	117 µs	58.5 µs	29.25 µs	117 µs	235 kHz
0x5	45 µs	90 µs	45 µs	22.5 µs	90 µs	360 kHz
0x6	380 µs	760 µs	380 µs	190 µs	760 µs	25 kHz
0x7	380 µs	760 µs	380 µs	190 µs	760 µs	25 kHz