SCDS487A October   2025  – December 2025 TMUX4819 , TMUX4821

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Absolute Maximum Ratings
  7. 6 ESD Ratings
  8. 7 Thermal Information
  9. 8 Recommended Operating Conditions
  10. 9 Source or Drain Continuous Current
  11. 10Source or Drain RMS Current
  12. 11Electrical Characteristics 
  13. 12Switching Characteristics 
  14. 13Typical Characteristics
  15. 14Parameter Measurement Information
    1. 14.1  On-Resistance
    2. 14.2  On-Leakage Current
    3. 14.3  Off-Leakage Current
    4. 14.4  Power-Off Leakage Current
    5. 14.5  Propagation Delay
    6. 14.6  tON (VDD) and tOFF (VDD) Time
    7. 14.7  Transition Time
    8. 14.8  Break-Before-Make
    9. 14.9  THD + Noise
    10. 14.10 Power Supply Rejection Ratio (PSRR)
    11. 14.11 Charge Injection
    12. 14.12 Bandwidth
    13. 14.13 Off Isolation
    14. 14.14 Crosstalk
  16. 15Detailed Description
    1. 15.1 Functional Block Diagram
    2. 15.2 Device Functional Modes
    3. 15.3 Feature Description
      1. 15.3.1 Beyond the Supply
      2. 15.3.2 Bidirectional Operation
      3. 15.3.3 Power-Off Protection
      4. 15.3.4 1.2V and 1.8V Logic Compatible Inputs
      5. 15.3.5 Integrated Pull-Down Resistor on Logic Pins
      6. 15.3.6 Fail-Safe Logic
  17. 16Application and Implementation
    1. 16.1 Application Information
    2. 16.2 Typical Applications
      1. 16.2.1 Audio Amplifier Switching
        1. 16.2.1.1 Design Requirements
        2. 16.2.1.2 Detailed Design Procedure
        3. 16.2.1.3 Application Curves
      2. 16.2.2 Smart Drug Delivery Flow Meters
        1. 16.2.2.1 Design Requirements
        2. 16.2.2.2 Detailed Design Procedure
        3. 16.2.2.3 Application Curve
    3. 16.3 Power Supply Recommendations
    4. 16.4 Layout
      1. 16.4.1 Layout Guidelines
      2. 16.4.2 Layout Example
  18. 17Device and Documentation Support
    1. 17.1 Documentation Support
      1. 17.1.1 Related Documentation
    2. 17.2 Receiving Notification of Documentation Updates
    3. 17.3 Support Resources
    4. 17.4 Trademarks
    5. 17.5 Electrostatic Discharge Caution
    6. 17.6 Glossary
  19. 18Revision History
  20. 19Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

16.2.2 Smart Drug Delivery Flow Meters

For smart drug delivery applications, a precise measurement of the dosage must be monitored. One very accurate architecture that is used is differential time of flight (TOF) using transducers. Many liquid flow sensor systems are higher attenuation compared to gas applications. In these high attenuation scenarios, a higher excitation voltage is used to significantly increase the signal to noise ratio (SNR). A bidirectional 2:1 multiplexer is used to switch the transmission and reception signals from the MCU to the transceivers without distortion.

Because the TMUX48xx can support signals beyond the supply, it is an excellent choice for handling this higher excitation voltage. The TMUX48xx can be used to switch up to -15V to 15V with a supply voltage from 1.8V to 5.5V, with an ultra-low on-resistance to minimize the impact on the signal quality. The supply can also be driven directly with a GPIO, allowing the user to put the device into ultra-low power mode. In this mode the TMUX48xx operates with powered-off protection, so any high voltage present on the inputs will not propagate to the outputs. This allows correct power up cycling and increases system robustness. Additionally, the TMUX48xx features excellent THD+N performance, so there is minimal impact to the signal quality through the switch.

TMUX4821 TMUX4819 Smart Drug Delivery Flow Meters Figure 16-4 Smart Drug Delivery Flow Meters