SNVAA47 May   2022 LP8732-Q1 , LP87521-Q1 , LP87524-Q1 , LP87561-Q1 , LP87562-Q1

 

  1. 1Abstract
    1.     Trademarks
  2. 1Design Parameters
  3. 2Power Solution
  4. 3Sequencing
    1. 3.1 Startup, Application Processor
    2. 3.2 Shutdown, Application Processor
    3. 3.3 Startup, Safety
    4. 3.4 Shutdown, Safety
    5. 3.5 Startup, RTC
    6. 3.6 Shutdown, RTC
  5. 4Schematic
  6. 5Software Drivers
  7. 6Recommended External Components
  8. 7Measurements
  9. 8Summary
  10. 9References

Abstract

This document details the design considerations of a power solution for the Semidrive X9P/X9U SoC (system-on-chip) power rails using the LP8756x-Q1, LP8752x-Q1, and LP8732-Q1 family power management ICs. Additional TPS74501-Q1 LDOs are used for the peripheral rails. This power solution assumes an input voltage of 5 V (±5%). If the system input voltage is higher, for example a car battery, a buck converter as a pre-regulator with high enough current capability should be used to generate a supply voltage of 5 V. Automotive qualified components are used for the power solution.

The LP875610B-Q1 has four buck converters configured to work as single 4-phase converter with maximum 16A load current for the core rail. LP87562R-Q1 is configured to work as 3-phase converter for the CPU rail and then additional single phase rail for the peripherals. LP87521S-Q1 has four buck converters configured to work as single 4-phase converter with maximum 10A load current for the GPU rail. LP875241J-Q1 is configured to work as four single phase converter for the peripheral rails. LP873248-Q1 is used for the safety power rails. These devices are OTP programmable, meaning default register values are set in TI production line to desired values for this platform without further need for customer to change settings through I2C bus. Full orderable part numbers for these OTP spins are LP875610BRNFRQ1, LP87562RRNFRQ1, LP87521SRNFRQ1, LP875241JRNFRQ1, and LP873248RHDRQ1. See the Technical Reference Manuals for the specific part numbers for more details on the OTP settings.

This power solution is an example how Semidrive X9P/U required rails can be powered with TI PMICs. Sequencing is handled through programmable startup and or shutdown delays of the PMICs and GPIOs and it only requires a single Enable signal from the system to initiate the sequencing. This power solution is possible to customize and optimize based on the actual use case regarding current requirements and used peripherals.