SBAS906 March 2018 TLV320ADC3100
PRODUCTION DATA.
The TLV320ADC3100 also has a digital volume-control block with a range from –12 dB to 20 dB (as shown in Table 2) in steps of 0.5 dB. This block is set by programming page 0, registers 83 and 84 for the left and right channels, respectively.
DESIRED GAIN
(dB) |
LEFT, RIGHT CHANNEL
PAGE 0, REGISTERS 83 AND 84, BITS 6:0 |
---|---|
–12 | 110 1000 |
–11.5 | 110 1001 |
–11 | 110 1010 |
... | ... |
–0.5 | 111 1111 |
0 | 000 0000 (default) |
0.5 | 000 0001 |
... | ... |
19.5 | 010 0111 |
20 | 010 1000 |
During volume control changes, the soft-stepping feature is used to avoid audible artifacts. The soft-stepping rate can be set to either 1 or 2 gain steps per sample. Soft-stepping can also be entirely disabled. This soft-stepping is configured via page 0, register 81, bits 1:0, and is common to soft-stepping control for the analog PGA. During power-down of an ADC channel, this volume control soft-steps down to –12 dB before powering down. Resulting from the soft-stepping control, soon after changing the volume control setting or powering down the ADC channel, the actual applied gain may be different from the one programmed through the control register. The TLV320ADC3100 provides feedback through the read-only flags in page 0, register 36, bit 7 for the left channel and page 0, register 36, bit 3 for the right channel.