SCDT002A april   2023  – june 2023 SN3257-Q1 , TS3A27518E-Q1


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I2S (Inter-IC Sound Bus) is a serial bus interface used for connecting audio devices together. Typically, a three-line protocol consisting of a Serial Clock (SCK), Word Select (WS) and Serial Data (SD) lines is used for these applications, though the need for a Word Select line is not always needed. A multiplexer can be used to help support multiple audio peripherals using a single I2S bus. Since these are passive, bidirectional parts they give the user the ability to either multiplex (MUX) or demultiplex (DEMUX) the respective signals.

GUID-20230323-SS0I-P5F0-186L-HVW3NBWFHFQX-low.svg Figure 1 2-Channel Implementation of I2S Using SN3257-Q1
GUID-20230323-SS0I-0VRG-SK2T-4RK6HQJSS5P1-low.svg Figure 2 3-Channel Implementation of I2S Using TS5A23157-Q1

Design Considerations

  • Select multiplexers with enough bandwidth and the appropriate channel count to support the needs of the application.
  • Powered-off protection can help protect against voltages present on the inputs when the multiplexer is not powered.
  • For battery powered systems, select multiplexers with low supply current to maximize battery life.
  • Learn about multiplexer parameters with TI Precision Labs Videos.
  • Ask a question on our TI E2E™ Design Support Forum.
Table 1 Recommended Parts
Part Number VCC Range (V) Configuration Bandwidth RON (Ω) Supply Current (μA) Features
SN3257-Q1 1.5 to 5.5 2:1 4-channel 2.0 GHz 5 40 1.8-V compatible control inputs, break-before-make, fail-safe logic, powered-off protection
TS3A27518E-Q1 1.65 to 3.6 2:1 6-channel 240 MHz 4.4 0.04 1.8-V compatible control inputs, break-before-make, powered-off protection
TMUX1574 1.5 to 5.5 2:1 4-channel 2.0 GHz 2 40 1.8-V compatible control inputs, fail-safe logic, Integrated pulldown resistor on logic pin, powered-off protection, supports input voltage beyond supply
TS5A23157-Q1 1.65 to 5.5 2:1 2-channel 220 MHz 15 0.01 Break-before-make, low charge injection, functional safety capable