Battery Mini-Breaker for Smartphone Battery Protection

Question

Problem: Battery Mini-Breaker for Smartphone Battery Protection. Solve this hands-on electronics task on EWskills.

Accepted Answer

1. Component Purpose

Smartphones are held against the user’s body. A lower trip temperature (77°C) provides early protection — cutting off the cell well before temperatures that could cause burns or trigger thermal runaway.

The single cell (4.2V max) requires relatively low voltage rating (≥9V provides large margin). Current rating of 6A–12A covers the 4A peak with derating while keeping the device compact.

Required: Breaker · 77°C trip · ≥9VDC · 6A–12A · Active · Littelfuse · RoHS

Battery-Mini-Breaker-for-Smartphone-Battery-Protection

2. How to Find It on DigiKey

Same category. Apply these filters:

Type → Breaker
Rated Functioning Temperature → 77°C
Current Rating (Amps) → 6A to 12A
Manufacturer → Littelfuse Inc.
Part Status → Active

Tip: Lower current rating (6A) provides better overcurrent sensitivity for a small 4A cell. Higher rating (12A) still provides overtemperature protection at 77°C but offers less overcurrent protection.

3. Key Specifications & What They Mean

Specification	Required	Why
Type	Breaker	Resettable thermal cutoff.
Trip Temperature	77°C	Early protection for body-contact device.
Voltage Rating	≥9VDC	Single cell max 4.2V; large margin.
Current Rating	6A to 12A	4A peak + margin; compact.
Part Status	Active	Currently manufactured.
Manufacturer	Littelfuse	Company AVL.
RoHS	Yes	Compliance required.

4. Selecting a Safe, Production-Ready Part

The filtered list will show matching parts. Before you pick one, check: Is it Active? Is stock available? Is the manufacturer reputable? Is a datasheet available?

Full checklist: How to Select a Safe, Production-Ready Component — EWskills Guide

5. Filtered DigiKey Link

➡ View Matching Parts — Littelfuse, Breaker, 77°C, 6–12A, ≥9VDC

39. Battery Mini-Breaker for Smartphone Battery Protection