STA326 STMicroelectronics, STA326 Datasheet - Page 50

• Manufacturer Part Number: STA326
• Description: DIG AUDIO SYSTEM, 2-CH, 36POWERSSOP
• Manufacturer: STMicroelectronics

Specifications of STA326

• Svhc: No SVHC (15-Dec-2010)
• No. Of Pins: 36
• Operating Temperature Range: -20°C To +85°C
• Supply Voltage Max: 36V
• Supply Voltage Min: 10V
• Termination T: RoHS Compliant
• Package / Case: PowerSO
• Interface: I2C
• Interface Type: I2C
• Rohs Compliant: Yes

User programmable processing
7.10
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Writing a set of coefficients to RAM
The mechanism for writing a set of coefficients to RAM provides a method of updating the
five coefficients corresponding to a given biquad (filter) simultaneously to avoid possible
unpleasant acoustic side-effects. When using this technique, the 8-bit address would
specify the address of the biquad b1 coefficient (for example 0, 5, 10, 15, …, 45 decimal),
and the STA326 will generate the RAM addresses as offsets from this base value to write
the complete set of coefficient data.
Table 63.
0
1
2
3
4
5
…
19
20
21
…
39
Index (decimal)
write 8 bits of starting address to I
write top 8 bits of coefficient b1 in I
write middle 8 bits of coefficient b1 in I
write bottom 8 bits of coefficient b1 in I
write top 8 bits of coefficient b2 in I
write middle 8 bits of coefficient b2 in I
write bottom 8 bits of coefficient b2 in I
write top 8 bits of coefficient a1 in I
write middle 8 bits of coefficient a1 in I
write bottom 8 bits of coefficient a1 in I
write top 8 bits of coefficient a2 in I
write middle 8 bits of coefficient a2 in I
write bottom 8 bits of coefficient a2 in I
write top 8 bits of coefficient b0 in I
write middle 8 bits of coefficient b0 in I
write bottom 8 bits of coefficient b0 in I
write 1 to WA bit in I
RAM block for biquads, mixing, and scaling
0x00
0x01
0x02
0x03
0x04
0x05
…
0x13
0x14
0x15
…
0x27
Index (Hex)
2
C address 0x26
Doc ID 11531 Rev 3
Channel 1 - Biquad 1
Channel 1 - Biquad 2
…
Channel 1 - Biquad 4
Channel 2 - Biquad 1
…
Channel 2 - Biquad 4
2
2
2
2
2
2
C register 0x16
C address 0x17
C address 0x1A
C address 0x1D
C address 0x20
C address 0x23
Description
2
2
2
2
2
2
2
2
2
2
C address 0x18
C address 0x1B
C address 0x1E
C address 0x21
C address 0x24
C address 0x19
C address 0x1C
C address 0x1F
C address 0x22
C address 0x25
C1H10 (b1/2)
C1H11 (b2)
C1H12 (a1/2)
C1H13 (a2)
C1H14 (b0/2)
C1H20
…
C1H44
C2H10
C2H11
…
C2H44
Coefficient
0x000000
0x000000
0x000000
0x000000
0x400000
0x000000
…
0x400000
0x000000
0x000000
…
0x400000
Default
STA326