TPS65381-Q1 (ACTIVE)

Multi-Rail Automotive Power Supply for Microcontrollers in Safety-Critical Applications


The TPS65381-Q1 device is a multi-rail power supply designed to supply microcontrollers (MCUs) in safety applications, such as those found in automotive and industrial applications. The device supports Texas Instruments’ TMS570LS series 16- bit or 32-bit RISC flash MCU and other MCUs with dual-core lockstep (LS) or loosely-coupled architectures (LC).

The TPS65381-Q1 device integrates multiple supply rails to power the MCU, CAN, or FlexRay, and an external sensor. An asynchronous-buck switch-mode power-supply converter with an internal FET converts the input battery voltage to a 6-V preregulator output. This 6-V preregulator supplies the other regulators. Furthermore, the device supports wake-up from IGNITION or wake-up from the CAN transceiver.

A fixed 5-V linear regulator with an internal FET is integrated to be used as, for example, a CAN supply. A second linear regulator, also with an internal FET, regulates the 6 V to a selectable 5-V or 3.3-V MCU I/O voltage.

The TPS65381-Q1 device comprises a linear regulator controller with an external FET and resistor divider that regulates the 6 V to an externally adjustable core voltage of between 0.8 V and 3.3 V.

The device comprises a sensor supply with short-to-ground and short-to-battery protection. Therefore this supply can power a sensor outside the electronic-control unit (ECU).

The device has an integrated charge pump to provide overdrive voltage for the internal regulators. Reverse-battery protection is obtained by using the charge-pump output to control an external NMOS transistor. This solution allows for a lower minimum-battery-voltage operation compared to a traditional reverse-battery blocking diode.

The device monitors undervoltage and overvoltage on all regulator outputs, battery voltage, and internal supply rails. A second bandgap reference, independent from the main bandgap reference, is used for the undervoltage and overvoltage monitoring, to avoid any drifts in the main bandgap reference from being undetected. In addition, regulator current-limits and temperature protections are implemented.

The TPS65381-Q1 safety functions feature a question-answer watchdog, MCU error-signal monitor, clock monitoring on internal oscillators, self-check on the clock monitor, CRC on non-volatile memory, a diagnostic output pin allowing the MCU to observe the internal analog and digital signals of the device, a reset circuit for the MCU, and an enable output to disable the safing-path or external power-stages on any detected system-failure. A built-in self-test (BIST) monitors the device functionality at start-up. A dedicated DIAGNOSTIC state allows the MCU to check TPS65381-Q1 safety functions.

The TPS65381-Q1 device is offered in a 32-pin HTSSOP PowerPAD package.


  • Qualified for Automotive Applications
  • AEC-Q100 Qualified With the Following
    • Device Temperature Grade 1: –40°C to +125°C
      Ambient Operating Temperature
    • Device HBM ESD Classification Level H2
    • Device CDM ESD Classification Level C3B
  • Multi-Rail Power Supply Supporting Among
    • Texas Instruments TMS570LS Series 16-Bit or
      32-Bit RISC Flash Microcontroller
  • Supply Rails
    • Input voltage range:
      • 5.8 V to 36 V (CAN, I/O, MCU Core, and
        Sensor-Supply Regulators Functional)
      • 4.5 V to 5.8 V (3.3-V I/O and MCU Core-
        Voltage Functional)
    • 6-V Asynchronous Switch-Mode Preregulator
      With Internal FET, 1.3-A Current-Limit, and
      Temperature Protection
    • 5-V (CAN) Supply Voltage, Linear Regulator
      With Internal FET, 350-mA Current-Limit, and
      Temperature Protection
    • 3.3-V or 5-V MCU I/O Voltage, Linear Regulator
      With Internal FET, 350-mA Current-Limit, and
      Temperature Protection
    • 0.8-V to 3.3-V Adjustable MCU Core Voltage,
      Linear Regulator Controller With External FET
    • Sensor Supply: Linear Tracking Regulator With
      Tracking Input, 100-mA Current-Limit,
      Temperature Protection, and Protection Against
      Short to Battery and Short to Ground
    • Charge Pump: Typ. 12 V Above Battery Voltage
  • Power Supply and System Monitoring
    • Independent Undervoltage and Overvoltage
      Monitoring on All Regulator Outputs, Battery
      Voltage, and Internal Supplies
    • Independent Bandgap Reference for Voltage
    • Independent Voltage References for Regulator
      References and Voltage Monitoring. Voltage-
      Monitoring Circuitry With Separate Battery
      Voltage Input Pin
    • Self-Check on all Voltage Monitoring (During
      Power-Up and After Power-Up Initiated by
      External MCU)
    • Junction Temperature Sensing With Shutdown
  • Microcontroller Interface
    • Open-Close Window or Question-Answer
      Watchdog Function
    • MCU Error-Signal Monitor (Supports TI TMS570
      MCU Mode or Other MCUs with PWM-Like
    • DIAGNOSTIC State for Performing Device Self-
      Tests, Diagnostics, and External Interconnect
    • Safe-State for Device and System Protection on
      Error Event Detection
    • Clock Monitor for Internal Oscillators
    • Self-Tests for Analog- and Digital-Critical
      Circuits Executed With Every Device Power Up
      or Activated by External MCU in DIAGNOSTIC
    • CRC on Non-Volatile Memory, Device, and
      System Configuration Registers
    • Reset circuit for MCU
    • Diagnostic Output Pin Allowing MCU to Observe
      Device Internal Analog and Digital Signals,
      Selectable Through Multiplexer
  • SPI
    • Configuring IC Registers
    • Watchdog Question-Answering
    • Diagnostic Readout
    • Compliant With 3.3-V and 5-V Logic Levels
  • Enable-Drive Output for Disabling Safing-Path
    or External Power-Stages on Any Detected
  • Wake-Up Through IGNITION Pin or CAN
    WAKEUP Pin
  • Package: 32-Pin HTSSOPPowerPAD™ IC

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Parametrics Compare all products in Power Management Multi-Channel IC (PMIC) Solutions

Regulated Outputs (#)
Processor Supplier
Processor Name
Vin (Min) (V)
Vin (Max) (V)
Vout (Max) (V)
Step-Up DC/DC Controller
Step-Down DC/DC Controller
Step-Up DC/DC Converter
Step-Down DC/DC Converter
Iout (Max) (A)
Iq (Typ) (mA)
Special Features
Operating Temperature Range (C)
Approx. Price (US$)
Texas Instruments    
Comm Control
Power Good
Thermal Shutdown
-40 to 125    
2.57 | 1ku    
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