AD1953YSTRL7 Analog Devices Inc, AD1953YSTRL7 Datasheet - Page 33

• Manufacturer Part Number: AD1953YSTRL7
• Description: IC DSP DAC AUDIO3CH/26BIT 48LQFP
• Manufacturer: Analog Devices Inc
• Series: SigmaDSP®r

Specifications of AD1953YSTRL7

• Rohs Status: RoHS non-compliant
• Number Of Bits: 26
• Data Interface: Serial
• Number Of Converters: 3
• Voltage Supply Source: Analog and Digital
• Power Dissipation (max): 540mW
• Operating Temperature: -40°C ~ 105°C
• Mounting Type: Surface Mount
• Package / Case: 48-LQFP
• For Use With: EVAL-AD1953EBZ - BOARD EVAL FOR AD1953 3CH 24BIT
• Settling Time: -

APPENDIX
Cookbook Formulae for Audio EQ Biquad Coefficients
(adapted from Robert Bristow-Johnson’s Internet posting)
For designing a Parametric EQ, follow the steps below.
1. Given:
2. Compute Intermediate Variables
3. Compute Coefficients
4. The transfer function implemented by the AD1953 is given by:
Note the inversion in sign of a1 and a2 relative to the more standard form. This form is used in this document because the AD1953
implements the difference equation using the formula below.
REV. 0
Y(n) = a1
Frequency
Q
dB_Gain
sample_rate
A = 10^(dB_Gain/40)
omega = 2
sn = sin(omega)
cs = cos(omega)
alpha = sn/(2
b0 = (1 + A
b1 = –2
b2 = (1 – (alpha/A))/(1 + (alpha/A))
a1 = 2
a2 = –(1 – (alpha/A))/(1 + (alpha/A))
H(Z) = (b0 + b1
×
×
×
cs/(1 + (alpha/A)) = –b1
y(n – 1) + a2
cs/(1 + (alpha/A))
×
×
π
×
alpha)/(1 + (alpha/A))
×
Q)
Frequency/Sample_Rate
×
Z
–1
+ b2
×
y(n – 2) + b0
×
Z
–2
)/(1 – a1
×
x(n) + b1
×
Z
–1
– a2
×
×
x(n – 1) + b2
Z
–2
)
–33–
×
x(n – 2)
AD1953