7.3.1.3 Using Multiple Devices With Shared Buses
The device has many supported features and flexible options that can be used in the system to seamlessly connect multiple PCMD3180 devices 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 operation, audio conferencing, noise cancellation, and so forth. Figure 29 shows a diagram of multiple PCMD3180 devices in a configuration where the control and audio data buses are shared.
The PCMD3180 consists of the following features to enable seamless connection and interaction of multiple devices using a shared bus:
- Supports up to four pin-programmable I2C slave addresses
- I2C broadcast simultaneously writes to (or triggers) all 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 GPOx pin can be configured as a secondary output data lane for the audio serial interface
- The GPIO1 or GPIx pin can be used in a daisy-chain configuration of multiple PCMD3180 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 PCMD3180 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 Devices With Shared TDM and I2C Bus application report for further details.