The device has many supported features
and flexible options that can be used in the system to seamlessly connect the
PCMD3140 and any other audio device by sharing a single common I2C
control bus and an audio serial interface bus. This architecture enables multiple
applications to be applied to a system that require a microphone array for
beam-forming operations, audio conferencing, noise cancellation, and so forth. Figure 7-13 shows a diagram of the PCMD3140 and PCMD3180 devices in a
configuration where the control and audio data buses are shared.
The PCMD3140 consists of the following
features to enable seamless connection and interaction of multiple devices using a
shared bus:
- I2C broadcast
simultaneously writes to (or triggers) the PCMD3140 and PCMD3180
devices
- Supports up to 64
configuration output channel slots for the audio serial interface
- Tri-state feature (with
enable and disable) for the unused audio data slots of the device
- Supports a bus-holder feature
(with enable and disable) to keep the last driven value on the audio
bus
- The GPIO1 or PDMCLK_GPO1 pin
can be configured as a secondary output data lane for the audio serial
interface
- The GPIO1 or PDMDINx_GPIx pin
can be used in a daisy-chain configuration of multiple devices
- Supports one BCLK cycle data
latching timing to relax the timing requirement for the high-speed
interface
- Programmable master and slave
options for the audio serial interface
- Ability to synchronize the
multiple devices for the simultaneous sampling requirement across
devices
The system can also connect multiple PCMD3140 devices in combination with
TLV320ADCx140 devices by sharing a single common I
2C control bus and an
audio serial interface bus. See the
Multiple TLV320ADCx140 &
TLV320ADCx120 Devices With Shared TDM and I2C Bus application
report for further details.