SPRSP79B February   2023  – December 2023 TDA4AH-Q1 , TDA4AP-Q1 , TDA4VH-Q1 , TDA4VP-Q1

PRODUCTION DATA  

  1.   1
  2. Features
  3. Applications
  4. Description
    1. 3.1 Functional Block Diagram
  5. Device Comparison
  6. Terminal Configuration and Functions
    1. 5.1 Pin Diagrams
    2. 5.2 Pin Attributes
      1.      10
      2.      11
    3. 5.3 Signal Descriptions
      1.      13
      2. 5.3.1  ADC
        1. 5.3.1.1 MCU Domain
          1.        16
          2.        17
          3.        18
      3. 5.3.2  DDRSS
        1. 5.3.2.1 MAIN Domain
          1.        21
          2.        22
          3.        23
          4.        24
      4. 5.3.3  GPIO
        1. 5.3.3.1 MAIN Domain
          1.        27
        2. 5.3.3.2 WKUP Domain
          1.        29
      5. 5.3.4  I2C
        1. 5.3.4.1 MAIN Domain
          1.        32
          2.        33
          3.        34
          4.        35
          5.        36
          6.        37
          7.        38
        2. 5.3.4.2 MCU Domain
          1.        40
          2.        41
        3. 5.3.4.3 WKUP Domain
          1.        43
      6. 5.3.5  I3C
        1. 5.3.5.1 MCU Domain
          1.        46
      7. 5.3.6  MCAN
        1. 5.3.6.1 MAIN Domain
          1.        49
          2.        50
          3.        51
          4.        52
          5.        53
          6.        54
          7.        55
          8.        56
          9.        57
          10.        58
          11.        59
          12.        60
          13.        61
          14.        62
          15.        63
          16.        64
          17.        65
          18.        66
        2. 5.3.6.2 MCU Domain
          1.        68
          2.        69
      8. 5.3.7  MCSPI
        1. 5.3.7.1 MAIN Domain
          1.        72
          2.        73
          3.        74
          4.        75
          5.        76
          6.        77
          7.        78
        2. 5.3.7.2 MCU Domain
          1.        80
          2.        81
      9. 5.3.8  UART
        1. 5.3.8.1 MAIN Domain
          1.        84
          2.        85
          3.        86
          4.        87
          5.        88
          6.        89
          7.        90
          8.        91
          9.        92
          10.        93
        2. 5.3.8.2 MCU Domain
          1.        95
        3. 5.3.8.3 WKUP Domain
          1.        97
      10. 5.3.9  MDIO
        1. 5.3.9.1 MAIN Domain
          1.        100
          2.        101
        2. 5.3.9.2 MCU Domain
          1.        103
      11. 5.3.10 UFS
        1. 5.3.10.1 MAIN Domain
          1.        106
      12. 5.3.11 CPSW2G
        1. 5.3.11.1 MAIN Domain
          1.        109
        2. 5.3.11.2 MCU Domain
          1.        111
      13. 5.3.12 SGMII
        1. 5.3.12.1 MAIN Domain
          1.        114
      14. 5.3.13 ECAP
        1. 5.3.13.1 MAIN Domain
          1.        117
          2.        118
          3.        119
      15. 5.3.14 EQEP
        1. 5.3.14.1 MAIN Domain
          1.        122
          2.        123
          3.        124
      16. 5.3.15 EPWM
        1. 5.3.15.1 MAIN Domain
          1.        127
          2.        128
          3.        129
          4.        130
          5.        131
          6.        132
          7.        133
      17. 5.3.16 USB
        1. 5.3.16.1 MAIN Domain
          1.        136
      18. 5.3.17 Display Port
        1. 5.3.17.1 MAIN Domain
          1.        139
      19. 5.3.18 PCIE
        1. 5.3.18.1 MAIN Domain
          1.        142
      20. 5.3.19 SERDES
        1. 5.3.19.1 MAIN Domain
          1.        145
          2.        146
          3.        147
          4.        148
      21. 5.3.20 DSI
        1. 5.3.20.1 MAIN Domain
          1.        151
          2.        152
      22. 5.3.21 CSI
        1. 5.3.21.1 MAIN Domain
          1.        155
          2.        156
          3.        157
      23. 5.3.22 MCASP
        1. 5.3.22.1 MAIN Domain
          1.        160
          2.        161
          3.        162
          4.        163
          5.        164
      24. 5.3.23 DMTIMER
        1. 5.3.23.1 MAIN Domain
          1.        167
        2. 5.3.23.2 MCU Domain
          1.        169
      25. 5.3.24 CPTS
        1. 5.3.24.1 MAIN Domain
          1.        172
        2. 5.3.24.2 MCU Domain
          1.        174
      26. 5.3.25 DSS
        1. 5.3.25.1 MAIN Domain
          1.        177
      27. 5.3.26 GPMC
        1. 5.3.26.1 MAIN Domain
          1.        180
      28. 5.3.27 MMC
        1. 5.3.27.1 MAIN Domain
          1.        183
          2.        184
      29. 5.3.28 OSPI
        1. 5.3.28.1 MCU Domain
          1.        187
          2.        188
      30. 5.3.29 Hyperbus
        1. 5.3.29.1 MCU Domain
          1.        191
      31. 5.3.30 Emulation and Debug
        1. 5.3.30.1 MAIN Domain
          1.        194
          2.        195
      32. 5.3.31 System and Miscellaneous
        1. 5.3.31.1 Boot Mode configuration
          1.        198
        2. 5.3.31.2 Clock
          1.        200
          2.        201
        3. 5.3.31.3 System
          1.        203
          2.        204
        4. 5.3.31.4 EFUSE
          1.        206
        5. 5.3.31.5 VMON
          1.        208
      33. 5.3.32 Power
        1.       210
    4. 5.4 Pin Connectivity Requirements
  7. Specifications
    1. 6.1  Absolute Maximum Ratings
    2. 6.2  ESD Ratings
    3. 6.3  Power-On-Hour (POH) Limits
    4. 6.4  Recommended Operating Conditions
    5. 6.5  Operating Performance Points
    6. 6.6  Electrical Characteristics
      1. 6.6.1  I2C, Open-Drain, Fail-Safe (I2C OD FS) Electrical Characteristics
      2. 6.6.2  Fail-Safe Reset (FS Reset) Electrical Characteristics
      3. 6.6.3  HFOSC/LFOSC Electrical Characteristics
      4. 6.6.4  eMMCPHY Electrical Characteristics
      5. 6.6.5  SDIO Electrical Characteristics
      6. 6.6.6  CSI2/DSI D-PHY Electrical Characteristics
      7. 6.6.7  ADC12B Electrical Characteristics
      8. 6.6.8  LVCMOS Electrical Characteristics
      9. 6.6.9  USB2PHY Electrical Characteristics
      10. 6.6.10 SerDes 2-L-PHY/4-L-PHY Electrical Characteristics
      11. 6.6.11 UFS M-PHY Electrical Characteristics
      12. 6.6.12 eDP/DP AUX-PHY Electrical Characteristics
      13. 6.6.13 DDR0 Electrical Characteristics
    7. 6.7  VPP Specifications for One-Time Programmable (OTP) eFuses
      1. 6.7.1 Recommended Operating Conditions for OTP eFuse Programming
      2. 6.7.2 Hardware Requirements
      3. 6.7.3 Programming Sequence
      4. 6.7.4 Impact to Your Hardware Warranty
    8. 6.8  Thermal Resistance Characteristics
      1. 6.8.1 Thermal Resistance Characteristics for ALY Package
    9. 6.9  Temperature Sensor Characteristics
    10. 6.10 Timing and Switching Characteristics
      1. 6.10.1 Timing Parameters and Information
      2. 6.10.2 Power Supply Sequencing
        1. 6.10.2.1 Power Supply Slew Rate Requirement
        2. 6.10.2.2 Combined MCU and Main Domains Power- Up Sequencing
        3. 6.10.2.3 Combined MCU and Main Domains Power- Down Sequencing
        4. 6.10.2.4 Isolated MCU and Main Domains Power- Up Sequencing
        5. 6.10.2.5 Isolated MCU and Main Domains Power- Down Sequencing
        6. 6.10.2.6 Independent MCU and Main Domains, Entry and Exit of MCU Only Sequencing
        7. 6.10.2.7 Independent MCU and Main Domains, Entry and Exit of DDR Retention State
        8. 6.10.2.8 Independent MCU and Main Domains, Entry and Exit of GPIO Retention Sequencing
      3. 6.10.3 System Timing
        1. 6.10.3.1 Reset Timing
        2. 6.10.3.2 Safety Signal Timing
        3. 6.10.3.3 Clock Timing
      4. 6.10.4 Clock Specifications
        1. 6.10.4.1 Input and Output Clocks / Oscillators
          1. 6.10.4.1.1 WKUP_OSC0 Internal Oscillator Clock Source
            1. 6.10.4.1.1.1 Load Capacitance
            2. 6.10.4.1.1.2 Shunt Capacitance
          2. 6.10.4.1.2 WKUP_OSC0 LVCMOS Digital Clock Source
          3. 6.10.4.1.3 Auxiliary OSC1 Internal Oscillator Clock Source
            1. 6.10.4.1.3.1 Load Capacitance
            2. 6.10.4.1.3.2 Shunt Capacitance
          4. 6.10.4.1.4 Auxiliary OSC1 LVCMOS Digital Clock Source
          5. 6.10.4.1.5 Auxiliary OSC1 Not Used
        2. 6.10.4.2 Output Clocks
        3. 6.10.4.3 PLLs
        4. 6.10.4.4 Module and Peripheral Clocks Frequencies
      5. 6.10.5 Peripherals
        1. 6.10.5.1  ATL
          1. 6.10.5.1.1 ATL_PCLK Timing Requirements
          2. 6.10.5.1.2 ATL_AWS[x] Timing Requirements
          3. 6.10.5.1.3 ATL_BWS[x] Timing Requirements
          4. 6.10.5.1.4 ATCLK[x] Switching Characteristics
        2. 6.10.5.2  CPSW2G
          1. 6.10.5.2.1 CPSW2G MDIO Interface Timings
          2. 6.10.5.2.2 CPSW2G RMII Timings
            1. 6.10.5.2.2.1 CPSW2G RMII[x]_REF_CLK Timing Requirements – RMII Mode
            2. 6.10.5.2.2.2 CPSW2G RMII[x]_RXD[1:0], RMII[x]_CRS_DV, and RMII[x]_RX_ER Timing Requirements – RMII Mode
            3. 6.10.5.2.2.3 CPSW2G RMII[x]_TXD[1:0], and RMII[x]_TX_EN Switching Characteristics – RMII Mode
          3. 6.10.5.2.3 CPSW2G RGMII Timings
            1. 6.10.5.2.3.1 RGMII[x]_RXC Timing Requirements – RGMII Mode
            2. 6.10.5.2.3.2 CPSW2G Timing Requirements for RGMII[x]_RD[3:0], and RGMII[x]_RCTL – RGMII Mode
            3. 6.10.5.2.3.3 CPSW2G RGMII[x]_TXC Switching Characteristics – RGMII Mode
            4. 6.10.5.2.3.4 RGMII[x]_TD[3:0], and RGMII[x]_TX_CTL Switching Characteristics – RGMII Mode
        3. 6.10.5.3  CSI-2
        4. 6.10.5.4  DDRSS
        5. 6.10.5.5  DSS
        6. 6.10.5.6  eCAP
          1. 6.10.5.6.1 Timing Requirements for eCAP
          2. 6.10.5.6.2 Switching Characteristics for eCAP
        7. 6.10.5.7  EPWM
          1. 6.10.5.7.1 Timing Requirements for eHRPWM
          2. 6.10.5.7.2 Switching Characteristics for eHRPWM
        8. 6.10.5.8  eQEP
          1. 6.10.5.8.1 Timing Requirements for eQEP
          2. 6.10.5.8.2 Switching Characteristics for eQEP
        9. 6.10.5.9  GPIO
          1. 6.10.5.9.1 GPIO Timing Requirements
          2. 6.10.5.9.2 GPIO Switching Characteristics
        10. 6.10.5.10 GPMC
          1. 6.10.5.10.1 GPMC and NOR Flash — Synchronous Mode
            1. 6.10.5.10.1.1 GPMC and NOR Flash Timing Requirements — Synchronous Mode
            2. 6.10.5.10.1.2 GPMC and NOR Flash Switching Characteristics – Synchronous Mode
          2. 6.10.5.10.2 GPMC and NOR Flash — Asynchronous Mode
            1. 6.10.5.10.2.1 GPMC and NOR Flash Timing Requirements – Asynchronous Mode
            2. 6.10.5.10.2.2 GPMC and NOR Flash Switching Characteristics – Asynchronous Mode
          3. 6.10.5.10.3 GPMC and NAND Flash — Asynchronous Mode
            1. 6.10.5.10.3.1 GPMC and NAND Flash Timing Requirements – Asynchronous Mode
            2. 6.10.5.10.3.2 GPMC and NAND Flash Switching Characteristics – Asynchronous Mode
          4. 6.10.5.10.4 GPMC0 IOSET
        11. 6.10.5.11 HyperBus
          1. 6.10.5.11.1 Timing Requirements for HyperBus
          2. 6.10.5.11.2 HyperBus 166 MHz Switching Characteristics
          3. 6.10.5.11.3 HyperBus 100 MHz Switching Characteristics
        12. 6.10.5.12 I2C
        13. 6.10.5.13 I3C
        14. 6.10.5.14 MCAN
        15. 6.10.5.15 MCASP
        16. 6.10.5.16 MCSPI
          1. 6.10.5.16.1 MCSPI — Controller Mode
          2. 6.10.5.16.2 MCSPI — Peripheral Mode
        17. 6.10.5.17 MMCSD
          1. 6.10.5.17.1 MMC0 - eMMC Interface
            1. 6.10.5.17.1.1 Legacy SDR Mode
            2. 6.10.5.17.1.2 High Speed SDR Mode
            3. 6.10.5.17.1.3 High Speed DDR Mode
            4. 6.10.5.17.1.4 HS200 Mode
            5. 6.10.5.17.1.5 HS400 Mode
          2. 6.10.5.17.2 MMC1/2 - SD/SDIO Interface
            1. 6.10.5.17.2.1 Default Speed Mode
            2. 6.10.5.17.2.2 High Speed Mode
            3. 6.10.5.17.2.3 UHS–I SDR12 Mode
            4. 6.10.5.17.2.4 UHS–I SDR25 Mode
            5. 6.10.5.17.2.5 UHS–I SDR50 Mode
            6. 6.10.5.17.2.6 UHS–I DDR50 Mode
            7. 6.10.5.17.2.7 UHS–I SDR104 Mode
        18. 6.10.5.18 CPTS
          1. 6.10.5.18.1 CPTS Timing Requirements
          2. 6.10.5.18.2 CPTS Switching Characteristics
        19. 6.10.5.19 OSPI
          1. 6.10.5.19.1 OSPI0 PHY Mode
            1. 6.10.5.19.1.1 OSPI With Data Training
              1. 6.10.5.19.1.1.1 OSPI Switching Characteristics – Data Training
            2. 6.10.5.19.1.2 OSPI Without Data Training
              1. 6.10.5.19.1.2.1 OSPI Timing Requirements – SDR Mode
              2. 6.10.5.19.1.2.2 OSPI Switching Characteristics – SDR Mode
              3. 6.10.5.19.1.2.3 OSPI Timing Requirements – DDR Mode
              4. 6.10.5.19.1.2.4 OSPI Switching Characteristics – DDR Mode
          2. 6.10.5.19.2 OSPI0 Tap Mode
            1. 6.10.5.19.2.1 OSPI0 Tap SDR Timing
            2. 6.10.5.19.2.2 OSPI0 Tap DDR Timing
        20. 6.10.5.20 OLDI
          1. 6.10.5.20.1 OLDI Switching Characteristics
        21. 6.10.5.21 PCIE
        22. 6.10.5.22 Timers
          1. 6.10.5.22.1 Timing Requirements for Timers
          2. 6.10.5.22.2 Switching Characteristics for Timers
        23. 6.10.5.23 UART
          1. 6.10.5.23.1 Timing Requirements for UART
          2. 6.10.5.23.2 UART Switching Characteristics
        24. 6.10.5.24 USB
      6. 6.10.6 Emulation and Debug
        1. 6.10.6.1 Trace
        2. 6.10.6.2 JTAG
          1. 6.10.6.2.1 JTAG Electrical Data and Timing
            1. 6.10.6.2.1.1 JTAG Timing Requirements
            2. 6.10.6.2.1.2 JTAG Switching Characteristics
  8. Detailed Description
    1. 7.1 Overview
    2. 7.2 Processor Subsystems
      1. 7.2.1 Arm Cortex-A72
      2. 7.2.2 Arm Cortex-R5F
      3. 7.2.3 DSP C71x
    3. 7.3 Accelerators and Coprocessors
      1. 7.3.1 GPU
      2. 7.3.2 VPAC
      3. 7.3.3 DMPAC
    4. 7.4 Other Subsystems
      1. 7.4.1 MSMC
      2. 7.4.2 NAVSS
        1. 7.4.2.1 NAVSS0
        2. 7.4.2.2 MCU_NAVSS
      3. 7.4.3 PDMA Controller
      4. 7.4.4 Power Supply
      5. 7.4.5 Peripherals
        1. 7.4.5.1  ADC
        2. 7.4.5.2  ATL
        3. 7.4.5.3  CSI
          1. 7.4.5.3.1 Camera Streaming Interface Receiver (CSI_RX_IF) and MIPI DPHY Receiver (DPHY_RX)
          2. 7.4.5.3.2 Camera Streaming Interface Transmitter (CSI_TX_IF)
        4. 7.4.5.4  CPSW2G
        5. 7.4.5.5  CPSW9G
        6. 7.4.5.6  DCC
        7. 7.4.5.7  DDRSS
        8. 7.4.5.8  DSS
          1. 7.4.5.8.1 DSI
          2. 7.4.5.8.2 eDP
        9. 7.4.5.9  VPFE
        10. 7.4.5.10 eCAP
        11. 7.4.5.11 EPWM
        12. 7.4.5.12 ELM
        13. 7.4.5.13 ESM
        14. 7.4.5.14 eQEP
        15. 7.4.5.15 GPIO
        16. 7.4.5.16 GPMC
        17. 7.4.5.17 Hyperbus
        18. 7.4.5.18 I2C
        19. 7.4.5.19 I3C
        20. 7.4.5.20 MCAN
        21. 7.4.5.21 MCASP
        22. 7.4.5.22 MCRC Controller
        23. 7.4.5.23 MCSPI
        24. 7.4.5.24 MMC/SD
        25. 7.4.5.25 OSPI
        26. 7.4.5.26 PCIE
        27. 7.4.5.27 SerDes
        28. 7.4.5.28 WWDT
        29. 7.4.5.29 Timers
        30. 7.4.5.30 UART
        31. 7.4.5.31 USB
        32. 7.4.5.32 UFS
  9. Applications, Implementation, and Layout
    1. 8.1 Device Connection and Layout Fundamentals
      1. 8.1.1 Power Supply Decoupling and Bulk Capacitors
        1. 8.1.1.1 Power Distribution Network Implementation Guidance
      2. 8.1.2 External Oscillator
      3. 8.1.3 JTAG and EMU
      4. 8.1.4 Reset
      5. 8.1.5 Unused Pins
      6. 8.1.6 Hardware Design Guide for JacintoTM 7 Devices
    2. 8.2 Peripheral- and Interface-Specific Design Information
      1. 8.2.1 LPDDR4 Board Design and Layout Guidelines
      2. 8.2.2 OSPI and QSPI Board Design and Layout Guidelines
        1. 8.2.2.1 No Loopback and Internal Pad Loopback
        2. 8.2.2.2 External Board Loopback
        3. 8.2.2.3 DQS (only available in Octal Flash devices)
      3. 8.2.3 USB VBUS Design Guidelines
      4. 8.2.4 System Power Supply Monitor Design Guidelines using VMON/POK
      5. 8.2.5 High Speed Differential Signal Routing Guidance
      6. 8.2.6 Thermal Solution Guidance
  10. Device and Documentation Support
    1. 9.1 Device Nomenclature
      1. 9.1.1 Standard Package Symbolization
      2. 9.1.2 Device Naming Convention
    2. 9.2 Tools and Software
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information
    1. 11.1 Packaging Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • ALY|1414
Thermal pad, mechanical data (Package|Pins)
Orderable Information

System Power Supply Monitor Design Guidelines using VMON/POK

The VMON1_ER_VSYS pin provides a way to monitor a system power supply. This system power supply is typically a single pre-regulated power source for the entire system. This supply is monitored by comparing the output of an external voltage divider circuit sourced by this supply with an internal voltage reference, with a power fail event being triggered when the voltage applied to VMON1_ER_VSYS drops below the internal reference voltage. The actual system power supply voltage trip point is determined by the system designer when selecting component values used to implement the external resistor voltage divider circuit. When designing the resistor divider circuit it is important to understand various factors which contribute to variability in the system power supply monitor trip point. The first thing to consider is the initial accuracy of the VMON1_ER_VSYS input threshold which has a nominal value of 0.45 V, with a variation of ±3%. Precision 1% resistors with similar thermal coefficient are recommended for implementing the resistor voltage divider. This minimizes variability contributed by resistor value tolerances. Input leakage current associated with VMON1_ER_VSYS must also be considered since any current flowing into the pin creates a loading error on the voltage divider output. The VMON1_ER_VSYS input leakage current may be in the range of 10 nA to 2.5 μA when applying 0.45 V.

Note:

The resistor voltage divider shall be designed such that its output voltage never exceeds the maximum value defined in Recommended Operating Conditions during normal operating conditions.

Figure 8-5 presents an example, where the system power supply is nominally 5 V and the maximum trigger threshold is 5 V - 10%, or 4.5 V.

For this example, it is important to understand which variables effect the maximum trigger threshold when selecting resistor values. It is obvious a device which has a VMON1_ER_VSYS input threshold of 0.45 V + 3% needs to be considered when trying to design a voltage divider that doesn’t trip until the system supply drops 10%. The effect of resistor tolerance and input leakage also needs to be considered, but how these contributions effect the maximum trigger point may not be obvious. When selecting component values which produce a maximum trigger voltage, the system designer must consider a condition where the value of R1 is 1% low and the value of R2 is 1% high combined with a condition where input leakage current for the VMON1_ER_VSYS pin is 2.5 μA. When implementing a resistor divider where R1 = 4.81 KΩ and R2 = 40.2 KΩ, the result is a maximum trigger threshold of 4.523 V.

Once component values have been selected to satisfy the maximum trigger voltage as described above, the system designer can determine the minimum trigger voltage by calculating the applied voltage that produces an output voltage of 0.45 V - 3% when the value of R1 is 1% high and the value of R2 is 1% low, and the input leakage current is 10 nA, or zero. Using an input leakage of zero with the resistor values given above, the result is a minimum trigger threshold of 4.008 V.

This example demonstrates a system power supply voltage trip point that ranges from 4.008 V to 4.523 V. Approximately 250 mV of this range is introduced by VMON1_ER_VSYS input threshold accuracy of ±3%, approximately 150 mV of this range is introduced by resistor tolerance of ±1%, and approximately 100 mV of this range is introduced by loading error when VMON1_ER_VSYS input leakage current is 2.5 μA.

The resistor values selected in this example produces approximately 100 μA of bias current through the resistor divider when the system supply is 4.5 V. The 100 mV of loading error mentioned above could be reduced to about 10 mV by increasing the bias current through the resistor divider to approximately 1 mA. So resistor divider bias current vs loading error is something the system designer needs to consider when selecting component values.

The system designer should also consider implementing a noise filter on the voltage divider output since VMON1_ER_VSYS has minimum hysteresis and a high-bandwidth response to transients. This could be done by installing a capacitor across R1 as shown in Figure 8-5. However, the system designer must determine the response time of this filter based on system supply noise and expected response to transient events.

Figure 8-5 presents an example, when the system power supply voltage is nominally 5 V and the desired trigger threshold is -10% or 4.5 V.

GUID-6769328C-5189-4498-A1C0-B9218DFFD8D6-low.gif Figure 8-5 System Supply Monitor Voltage Divider Circuit

The VMON2_IR_VCPU pin provides a way to monitor VDD_CPU power supply. Must be externally connected as close as possible to VDD_CPU pin on the board. SoCs that have a VMON6_IR_VEXT0P8 can optionally monitor other domains such as VDD_CORE or VDD_MCU. Similarly, those signals should be as close as possible to VDD_CORE or VDD_MCU pin on the board.

The VMON3_IR_VEXT1P8 and VMON4_IR_VEXT1P8 pins provide a way to monitor an external 1.8-V power supply. The VMON5_IR_VEXT3P3 pin provides a way to monitor an external 3.3-V power supply. An internal resistor divider with software control is implemented inside the SoC. Software can program the internal resistor divider to create appropriate under voltage and over voltage interrupts. These pins should not be sourced from an external resistor divider. If the monitored voltage requires adjustment, be sure to buffer the divided voltage prior connecting to monitor pin.