Related
Recommended
Alex Bhandari-Young
Other Parts Discussed in Post: TPS274C65, TPS2HCS10-Q1

Covers the SPI communication layer on smart eFuse and other digitally-controlled HSS devices.

Device Type

Question

Answer

HSS eFuse

How do I calculate the CRC for SPI frames on smart eFuse HSS devices?

Both TPS2HCS10-Q1 and TPS274C65, use CRC-4-ITU: polynomial x⁴+x+1 (0x03), starting value 1111 (0x0F).

For data sent TO the device: run the standard algorithm. For data received FROM TPS2HCS10-Q1: additionally XOR the result by 0x02 (or run a second pass on '1111'). TPS274C65 does not need this extra step.

Verified C code implementations are provided in the linked E2E FAQ posts. The CRC is optional but strongly recommended for functional safety applications.

Sources:
E2E FAQ: CRC - TPS274C65
E2E FAQ: CRC - TPS2HCS10-Q1

HSS eFuse

When should I choose SPI interface over GPIO, and what extra capability do I get?

Below are some common examples where SPI devices provide a significant advantage over GPIO devices:

  • Quantitative data is needed (current, voltage, and/or temperature) as ADC readings rather than just a fault flag.
  • The design requires many channels and it is helpful to reduce MCU pin count via SPI daisy-chain configuration.
  • Programmability of I²T curves and other configuration settings through software is required.

The referenced app note, Enabling SPI Communication, covers SPI initialization, register map, and daisy-chain wiring.

Sources: 
SLVAEX4A: Enabling SPI Communication
SLVAFN1: Software Configurable HSS for Zone Controllers