SNIS241 September   2025 TMP461-EP

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Information
  6. 5 Pin Configuration and Functions
  7. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Two-Wire Timing Requirements
    7. 6.7 Timing Diagrams
    8. 6.8 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Temperature Measurement Data
        1. 7.3.1.1 Decoding Temperature Data
      2. 7.3.2 Series Resistance Cancellation
      3. 7.3.3 Differential Input Capacitance
      4. 7.3.4 Filtering
      5. 7.3.5 Sensor Fault
      6. 7.3.6 ALERT and THERM Functions
    4. 7.4 Device Functional Modes
      1. 7.4.1 Shutdown Mode (SD)
    5. 7.5 Programming
      1. 7.5.1 Serial Interface
        1. 7.5.1.1 Bus Overview
        2. 7.5.1.2 Bus Definitions
        3. 7.5.1.3 Serial Bus Address
        4. 7.5.1.4 Read and Write Operations
        5. 7.5.1.5 Timeout Function
        6. 7.5.1.6 High-Speed Mode
      2. 7.5.2 General-Call Reset
  9. 8 Register Map
    1. 8.1 Register Information
      1. 8.1.1  Pointer Register
      2. 8.1.2  Local and Remote Temperature Registers
      3. 8.1.3  Status Register
      4. 8.1.4  Configuration Register
      5. 8.1.5  Conversion Rate Register
      6. 8.1.6  One-Shot Start Register
      7. 8.1.7  Channel Enable Register
      8. 8.1.8  Consecutive ALERT Register
      9. 8.1.9  η-Factor Correction Register
      10. 8.1.10 Remote Temperature Offset Register
      11. 8.1.11 Manufacturer Identification Register
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curve
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Receiving Notification of Documentation Updates
    2. 10.2 Related Documentation
    3. 10.3 Support Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

Package Options

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

9.4.1 Layout Guidelines

Remote temperature sensing on the TMP461-EP device measures very small voltages using very low currents; therefore, noise at the device inputs must be minimized. Most applications using the TMP461-EP have high digital content, with several clocks and logic-level transitions that create a noisy environment. Layout must adhere to the following guidelines:

  1. Place the TMP461-EP device as close to the remote junction sensor as possible.
  2. Route the D+ and D– traces next to each other and shield them from adjacent signals through the use of ground guard traces, as shown in Figure 9-5. If a multilayer PCB is used, bury these traces between the ground or V+ planes to shield them from extrinsic noise sources. 5mil (0.127mm) PCB traces are recommended.
  3. Minimize additional thermocouple junctions caused by copper-to-solder connections. If these junctions are used, make the same number and approximate locations of copper-to-solder connections in both the D+ and D– connections to cancel any thermocouple effects.
  4. Use a 0.1μF local bypass capacitor directly between the V+ and GND of the TMP461-EP device. For optimum measurement performance, minimize filter capacitance between D+ and D– to 1000pF or less. This capacitance includes any cable capacitance between the remote temperature sensor and the TMP461-EP device.
  5. If the connection between the remote temperature sensor and the TMP461-EP device is less than 8in (20.32cm) long, use a twisted-wire pair connection. For lengths greater than 8 in, use a twisted, shielded pair with the shield grounded as close to the TMP461-EP device as possible. Leave the remote sensor connection end of the shield wire open to avoid ground loops and 60Hz pickup.
  6. Thoroughly clean and remove all flux residue in and around the pins of the TMP461-EP device to avoid temperature offset readings as a result of leakage paths between D+ and GND, or between D+ and V+.
TMP461-EP Suggested PCB Layer Cross-Section
NOTE: Use a minimum of 5mil (0.127mm) traces with 5mil spacing.
Figure 9-5 Suggested PCB Layer Cross-Section