CDB3318 Cirrus Logic Inc, CDB3318 Datasheet - Page 19

• Manufacturer Part Number: CDB3318
• Description: Eval Bd - 8-channel Digital Vol Cntrl
• Manufacturer: Cirrus Logic Inc

Specifications of CDB3318

• Main Purpose: Audio, Volume Control
• Embedded: No
• Utilized Ic / Part: CS3318
• Primary Attributes: 8 Single-Ended Analog Inputs and Outputs, USB or RS232 Interface
• Secondary Attributes: Graphical User Interface
• Description/function: Audio DSPs
• Operating Supply Voltage: 8 V to 9 V
• Product: Audio Modules
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• For Use With/related Products: CS3310
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant, Contains lead / RoHS non-compliant
• Other names: 598-1497

DS693F1
5.5
5.5.1
5.5.2
Volume Controls
The CS3318 provides comprehensive volume control functionality, allowing each channel’s volume to be
changed on an individual or master basis. Refer to the
page 17
The CS3318 incorporates zero-crossing detection capabilities, and all volume changes are implemented as
dictated by the zero-crossing detection settings (see
Individual Channel Volume Controls
The CS3318 provides 8 individual channel volume controls. These controls can be used to independently
gain and/or attenuate each of the input/output channels over a range of +22 dB to -96 dB in ¼ dB steps.
Each channel has a corresponding Ch. X Volume register used to gain or attenuate the channel from
+22 dB to -96 dB in ½ dB steps. The ¼ dB Control register contains one bit per channel used to add an
additional ¼ dB gain to the channel’s volume as set by its Ch. X Volume register.
Master Volume Controls
The CS3318 master volume controls allow the user to simultaneously gain or attenuate a user defined set
of channels from +22 dB to -96 dB in ¼ dB increments. A total of 3 master volume controls, Master 1,
Master 2, and Master 3, are provided for comprehensive and flexible control.
Each master volume control has a corresponding Master X Volume register which is used to gain or at-
tenuate the control’s respective unmasked channels from +22 dB to -96 dB in ½ dB steps. The LSB of the
corresponding Master X Control register contains one bit used to add an additional ¼ dB gain to the mas-
ter volume control’s value as set by its Master X Volume register.
As discussed in the
trol has a corresponding Master X Mask register which allows the user to select which channels are af-
fected by the control. By default, each master control is configured to affect all channels within the device.
The effective volume setting of an individual channel is determined by the following equation:
EffVol
In this equation, EffVol
“N” as determined by the its constituent volume settings within the CS3318. The effective volume is limited
to the range of +22 dB to -96 dB; see “Volume Limits” on page 20.
Individual
trol register and ¼ dB bit (see
Master X is the Master X volume setting in dB as set by the master volume control registers and their re-
spective ¼ dB bits.
Mask X
This volume control architecture in combination with the multiple group addressing capabilities of the
CS3318 (as detailed in
multiple devices in a system while eliminating the system controller overhead typically associated digitally
driven analog volume control devices.
Referenced Control
Ch. X Volume ......................
¼ dB Control .......................
ChN
for complete details about the configuration of the CS3318’s individual and master controls.
ChN
ChN
= Individual
is the channel N mask bit associated with the Master X volume control setting.
is the individual channel volume setting in dB as set by the channel’s individual volume con-
“Volume & Muting Control Architecture” section on page
ChN
ChN
Register Location
“Ch 1-8 Volume - Addresses 01h - 08h” on page 31
“¼ dB Control - Address 09h” on page 32
section 5.8.2 on page
+ (Master 1 & Mask 1
represents the actual gain or attenuation level, in dB, of the individual channel
“Individual Channel Volume Controls” on page
Equation 1. Effective Volume Setting
24) allows easy volume control of multiple channels across
ChN
) + (Master 2 & Mask 2
“Zero-Crossing Detection” on page
“Volume & Muting Control Architecture” section on
ChN
17, each master volume con-
) + (Master 3 & Mask 3
19).
22).
CS3318
ChN
19
)