SLVA528D September   2012  – August 2021 TPS65381-Q1 , TPS65381A-Q1

 

  1.   Trademarks
  2. 1Introduction
  3. 2Product Overview
    1. 2.1 Safety Functions and Diagnostics Overview
    2. 2.2 Target Applications
    3. 2.3 Product Safety Constraints
  4. 3Development Process for Management of Systematic Faults
    1. 3.1 TI New-Product Development Process
  5. 4TPS65381x-Q1 Product Architecture for Management of Random Faults
    1. 4.1 Device Operating States
    2.     Device Operating States (continued)
    3. 4.2 NRES (MCU Reset) Driver and ENDRV (SAFING Path Enable) Driver
  6. 5TPS65381x-Q1 Architecture Safety Mechanisms and Assumptions of Use
    1. 5.1 Power Supply
    2. 5.2 Regulated Supplies
      1. 5.2.1 VDD6 Buck Switch-Mode Supply
      2. 5.2.2 VDD5 Linear Supply
      3. 5.2.3 VDD3/5 Linear Supply
      4. 5.2.4 VDD1 Linear Supply
      5. 5.2.5 VSOUT1 Linear Supply
      6. 5.2.6 Charge Pump
    3. 5.3 Diagnostic, Monitoring, and Protection Functions
      1. 5.3.1 External MCU Fault Detection and Management
        1. 5.3.1.1 External MCU Error Signal Monitor (MCU ESM)
        2. 5.3.1.2 Watchdog Timer
      2. 5.3.2 Voltage Monitor (VMON)
      3. 5.3.3 Loss-of-Clock Monitor (LCMON)
      4. 5.3.4 Junction Temperature Monitoring and Current Limiting
      5. 5.3.5 Analog and Digital MUX (AMUX and DMUX) and Diagnostic Output Pin (DIAG_OUT)
      6. 5.3.6 Analog Built-In Self-Test (ABIST)
      7. 5.3.7 Logic Built-In Self-Test (LBIST)
      8. 5.3.8 Device Configuration Register Protection
  7. 6Application Diagrams
    1. 6.1 TPS65381x-Q1 With TMS570
    2. 6.2 TPS65381x-Q1 With C2000
    3. 6.3 TPS65381x-Q1 With TMS470
  8. 7TPS65381x-Q1 as Safety Element out of Context (SEooC)
    1. 7.1 TPS65381x-Q1 Used in an EV/HEV Inverter System
    2. 7.2 SPI Note
  9. 8Revision History

5.3.5 Analog and Digital MUX (AMUX and DMUX) and Diagnostic Output Pin (DIAG_OUT)

A multiplexer switches critical analog and digital signals to the DIAG_OUT pin for monitoring by the MCU. The DIAG_CFG_CTRL and DIAG_MUX_SEL registers program the multiplexer.

Connecting the DIAG_OUT output pin to the MCU ADC input provides redundant monitoring of safety-critical supply voltages.

The analog MUX (AMUX) and digital MUX (DMUX) facilitates external pin interconnect tests by feeding back the input pin state, internal module self-test status, or safety-critical comparator output.

Refer to the data sheet for details on using the DIAG_OUT pin for AMUX and DMUX.

GUID-474CB081-B4F3-4ECA-A65C-D24EEE132027-low.gif
Marked analog signals put out with divider ratio.
If the application must measure analog signals with an MCU ADC and monitor digital signals with an MCU GPIO, the application design must assure the GPIO input stage does not affect the ADC measurements. If isolating the MCU GPIO is not possible within the MCU, the application design must achieve the necessary isolation externally
Figure 5-9 Diagnostic Output Pin, DIAG_OUT
Note:

When enabling the DIAG_OUT MUX while using SPI communication: the SDO is not in the high-impedance state while the NCS pin is HIGH and the DIAG_OUT MUX is enabled. Software or hardware modification may be required. For hardware modifications, check the SDO threshold level and drive capability if resistors are used to adjust the voltage level of the SDO pin on the SPI bus.