TAS5713 datasheet(34/72 Pages) TI2

34 / 72 page

Bit

–23

S_xx.xxxx_xxxx_xxxx_xxxx_xxxx_xxx

Bit

–5

Bit

–1

2 Bit

SignBit

2 Bit

M0125-01

TAS5713

SLOS637A – DECEMBER 2009 – REVISED AUGUST 2010

www.ti.com

BANK SWITCHING

The TAS5713 uses an approach called bank switching together with automatic sample-rate detection. All

processing features that must be changed for different sample rates are stored internally in three banks. The

user can program which sample rates map to each bank. By default, bank 1 is used in the 32-kHz mode, bank 2

is used in the 44.1/48-kHz mode, and bank 3 is used for all other rates. Combined with the clock-rate

autodetection feature, bank switching allows the TAS5713 to detect automatically a change in the input sample

rate and switch to the appropriate bank without any MCU intervention.

An external controller configures bankable locations (0x29–0x36, 0x3A–0x3F, and 0x58–0x5F) for all three banks

during the initialization sequence.

If automatic bank switching is enabled (register 0x50, bits 2:0) , then the TAS5713 automatically swaps the

coefficients for subsequent sample-rate changes, avoiding the need for any external controller intervention for a

sample-rate change.

By default, bits 2:0 have the value 000; indicating that bank switching is disabled. In that state, updates to

bankable locations take immediate effect. A write to register 0x50 with bits 2:0 being 001, 010, or 011 brings the

system into the coefficient-bank-update state update bank1, update bank2, or update bank3, respectively. Any

subsequent write to bankable locations updates the coefficient banks stored outside the DAP. After updating all

the three banks, the system controller should issue a write to register 0x50 with bits 2:0 being 100; this changes

the system state to automatic bank switching mode. In automatic bank switching mode, the TAS5713

automatically swaps banks based on the sample rate.

Command sequences for updating DAP coefficients can be summarized as follows:

Bank switching disabled (default): DAP coefficient writes take immediate effect and are not

influenced by subsequent sample-rate changes.

Bank switching enabled:

(a)

Update bank-1 mode: Write 001 to bits 2:0 of register 0x50. Load the 32-kHz coefficients.

(b)

Update bank-2 mode: Write 010 to bits 2:0 of register 0x50. Load the 48-kHz coefficients.

(c)

Update bank-3 mode: Write 011 to bits 2:0 of register 0x50. Load the other coefficients.

(d)

Enable automatic bank switching by writing 100 to bits 2:0 of reg 0x50.

26-Bit 3.23 Number Format

All mixer gain coefficients are 26-bit coefficients using a 3.23 number format. Numbers formatted as 3.23

numbers means that there are 3 bits to the left of the binary point and 23 bits to the right of the binary point. This

is shown in Figure 48 .

Figure 48. 3.23 Format

Submit Documentation Feedback

Product Folder Link(s): TAS5713

TAS5713 датащи(PDF) 34 Page - Texas Instruments

TAS5713 датащи(HTML) 34 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72

датащи скачать

ссылки URL