Definitions for technical terms and acronyms related to HSS & controllers.
Term
Definition
/FLT, /ST
Active-low fault-flag output pins that signal a fault condition (open load, short circuit, thermal shutdown, etc.) to the MCU.
...
Covers additional application-specific FAQs that don't fit neatly into the categories above, such as bench-test setup pitfalls and multi-board automotive lighting diagnostics.
Topic
Question
Answer
Testing & Bench Behavior
Device T...
Covers the evaluation tools available for HSS devices: the Smart Fuse Configurator GUI/firmware for EVM-based bring-up, and the Excel-based current-limit/junction-temperature calculator for design-time analysis.
Device Type
Question
Answer...
Covers TI's smart eFuse high-side switches, which replicate a melting fuse's I²T (current² × time) response digitally, including how the protection curve is configured.
Device Type
Question
Answer
HSS eFuse
How does I...
Covers how to choose between an integrated-FET high-side switch and an external-FET high-side switch controller based on current level and application.
Device Type
Question
Answer
HSSC
When should I use a high-side switch controller ...
Explains why automotive and chassis-grounded systems generally require high-side rather than low-side switching, covering ground-shift, shared-return interruption, and shock-hazard considerations.
Device Type
Question
Answer
HSS
Why ...
Covers how to estimate junction temperature using the RθJA/RθJB/ΨJT values, and how Rds(on) temperature drift must be fed back into the thermal budget calculation.
Device Type
Question
Answer
HSS
How do I estimate jun...
Clarifies that the ‘extended supply voltage’ rating on HSS datasheets covers transient events only (cold crank, load dump) and is not a nominal continuous-operation rating.
Device Type
Question
Answer
HSS
What does the 'e...
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 sm...
Other Parts Discussed in Post: TPS2HCS08-Q1
Covers how open-load, short-circuit, and short-to-battery faults are detected and reported, and how to distinguish between fault types on devices with a single shared fault pin versus SPI fault registers.
...
Covers how TI high-side switches and controllers respond to short-circuit, loss-of-ground, and overstress conditions, including thermal shutdown, and the interaction between current limit and FET SOA in controller designs.
Device Type
Questi...
Covers the practical frequency limits and thermal considerations for switching a high-side switch as a PWM output, including why very high frequencies require an external low-side switch instead.
Device Type
Question
Answer
HSS
What ...
Covers device behavior driving different load types including resistive, capacitive, and inductive, as well as specifics for each such as the VDS clamp for inductive turn-off, inrush handling for capacitive and bulb loads, and paralleling chann...
Other Parts Discussed in Post: TPS272C45
Covers the inrush-current-limit feature and dV/dt slew control used to survive the current surge from cold filaments and large capacitive loads, and why the current limit alone should not be relied on as the p...
Other Parts Discussed in Post: INA228, TPS272C45
Covers value selection and details relating to the current-sense and current-limit device pins (RILIM, RSNS, SNS/CS) on TI high-side switches, including accuracy, temperature drift, and using the sense...
