The reference value that is required for temperature bandwidth compensation is the contents of the
TC_PG_STATUS register. This represents a counter that increments with every pulse generated by the
DW1000 IC’s internal pulse generator. Intuitively, this count value (referred to as PG_COUNT) will vary
inversely with the TC_PGDELAY value – if the delay between pulses increases, the number of pulses within a
given timeframe will decrease, and vice versa. DELAY_CNT represents a counter that increments with every
pulse generated by the DW1000 IC’s internal pulse generator.
The TC_PGDELAY value will not give the same bandwidth for varying temperatures. The PG_COUNT value,
however, will give a stable bandwidth across all temperatures. It is taken as a reference as the DW1000 has a
pulse generator auto-calibration procedure; the procedure takes a PG_COUNT value and calculates the
TC_PGDELAY value from this. This TC_PGDELAY value can then be programmed in to give the desired
bandwidth.
More details on using these registers for bandwidth temperature compensation can be found in the
following application note : APS023 Part 2.
7.2.43.6 Sub-Register 0x2A:0B – TC_PGDELAY
Transmitter Calibration –Pulse Generator Delay
Register file: 0x2A – Transmitter Calibration block, sub-register 0x0B is an 8-bit configuration register for
setting the Pulse Generator Delay value. This effectively sets the width of transmitted pulses effectively
setting the output bandwidth. The value used here depends on the TX channel selected by the TX_CHAN
configuration in Register file: 0x1F – Channel Control. Recommended values are given in Table 40 below;
note however that these values may need to be tuned for spectral regulation compliance depending on
external circuitry.
Table 40: Sub-Register 0x2A:0B – TC_PGDELAY recommended values
8-bit value to program to
Sub-Register 0x2A:0B – TC_PGDELAY
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