I’ll research the 0805L110WR manufacturer data, verify practical integration guidance and alternatives, and save the cited application guide in the project files.
I found the manufacturer ratings and two alternative candidates; neither should be treated as an unconditional drop-in replacement. The citation-backed datasheet lookup is still processing, so I’m resolving that before finalizing the guide.
The Littelfuse and Bourns PDF lookups did not finish verification, so I’ll clearly mark those gaps rather than present the guide as fully verified. I have verified the Bel alternative’s datasheet and checked sourcing links; the guide will distinguish replacement candidates from confirmed drop-ins.
The Littelfuse 0805L110WR is an 0805 surface-mount polymeric positive-temperature-coefficient (PPTC) resettable fuse, listed by the manufacturer with a 1.1 A hold current and 6 V maximum voltage. Its common use is series overcurrent protection for low-voltage peripheral power, including USB peripherals and battery-powered electronics, where resettable protection is preferred over replacing a one-time fuse. Manufacturer product page
It remains a research draft: Littelfuse and Bourns PDF verification could not be completed, and those gaps are explicitly flagged. Before publication, the remaining priorities are confirming datasheet revisions, land patterns, and purchasing terms; no unconditional drop-in replacement is claimed.
The Littelfuse 0805L110WR is an 0805 surface-mount polymeric positive-temperature-coefficient (PPTC) resettable fuse, listed by the manufacturer with a 1.1 A hold current and 6 V maximum voltage. Its common use is series overcurrent protection for low-voltage peripheral power, including USB peripherals and battery-powered electronics, where resettable protection is preferred over replacing a one-time fuse. Manufacturer product page
Verification status — research draft, October 7, 2026: The manufacturer product page was retrieved, but the Littelfuse PDF evidence lookup returned insufficient evidence and its distributor-hosted copy remained pending after retry. Values below identified as PDF-unverified are manufacturer-page listings or preliminary search leads, not completed datasheet verification. The Bourns PDF lookup also remained pending; the Bel alternative's cited electrical and selected mechanical data were verified. This guide is not a production substitution approval.
1. Quick Specifications
The product page does not organize these specifications into an IC-style “Absolute Maximum Ratings” versus “Recommended Operating Conditions” table. The classifications below distinguish maximum withstand limits, conditional operating specifications, and reference values without relabeling everything as a continuous operating rating.
Table
Parameter
Listed value
Classification and practical interpretation
Verification
Maximum voltage, Vmax
6 V
Maximum device withstand rating; not a regulated output or overvoltage clamp. Evaluate the voltage across the device during a fault.
Manufacturer page; PDF-unverified
Maximum fault current, Imax
100 A
Maximum fault-current rating, not permissible continuous load current and not a zero-leakage interrupting rating.
Manufacturer page; PDF-unverified
Hold current, Ihold
1.10 A
Conditional no-trip specification. PDF search leads specify 20°C still air; that condition remains PDF-unverified. Do not assume 1.10 A capability at every temperature.
Manufacturer page; condition PDF-unverified
Trip current, Itrip
2.00 A
Trip specification, not a precise electronic current-limit threshold. Its temperature and test conditions require final PDF verification.
Manufacturer page; PDF-unverified
Maximum time to trip
0.10 s at 8.00 A
Conditional fault-response specification. Do not apply 100 ms to a 2 A overload.
Manufacturer page; PDF-unverified
Initial resistance, Rmin
0.050 Ω
Minimum value; not typical or worst-case series resistance.
Manufacturer page; PDF-unverified
Post-trip/reflow resistance, R1max
0.160 Ω
Account for this in voltage-drop analysis; exact measurement/recovery conditions require PDF verification. It is not the hot tripped-state resistance.
Manufacturer page; PDF-unverified
Power, Pd
0.8 W
Manufacturer page labels PDMAX; PDF search leads identify tripped-state dissipation. Do not treat it as a normal-state resistor power rating.
Interpretation PDF-unverified
Operating temperature
−40°C to +85°C
Ambient operating range; hold current must be thermally derated.
Manufacturer page; PDF-unverified
Package
0805 surface mount, two terminals
Use the PPTC's manufacturer land pattern, not an assumed resistor footprint.
Manufacturer series page; PDF-unverified
Body envelope
Search lead: length 2.00–2.20 mm, width 1.20–1.50 mm, thickness 0.80–1.40 mm
Unverified: distributor dimensions conflict; obtain the current mechanical drawing before footprint or enclosure release.
PDF lookup unresolved
Terminal/pad pitch
Not verified
No connector-style pitch is established here. Pad center spacing must come from the recommended land-pattern drawing.
Unverified
Source for the manufacturer-listed values: Littelfuse 0805L110 product page. A separate manufacturer-recommended continuous-current margin was not verified.
Temperature derating: The distributor-hosted Littelfuse PDF search lead lists 0.92 A at 40°C, 0.75 A at 60°C, and 0.52 A at 85°C for 0805L110. These values remain PDF-unverified and must not be used as approved design limits until the temperature table, revision, and notes are checked. The practical implication is to select against the temperature near the fuse inside the enclosure, not room temperature alone.
2. Pinout & Connections
This is a two-terminal series protection element, not an IC with supply, ground, or control pins. The following numbering is a schematic convention; manufacturer physical pin numbering and an explicit polarity statement were not verified.
Table
Pin Number
Pin Name
Description
Best Practice
1, schematic convention
Terminal A / VIN side
One end of the series protection element
Connect to the positive source rail near the power entry point; verify the library's pad-to-pin mapping.
2, schematic convention
Terminal B / protected side
Other end of the series protection element
Connect to the protected load rail. Do not connect directly to GND or place the fuse across the supply.
No enable connection, pull-up, pull-down, or third ground terminal is required by this two-terminal topology. Series placement follows Littelfuse's PPTC application guidance.
3. Standard Application Circuit
Typical engineering topology: low-voltage peripheral power protection
Text
Positive supply ── F1: 0805L110WR ── VPROTECTED ── Load or regulator
Supply return ──────────────────── GND ────────── Load return
│
Load-required decoupling/bulk capacitance
connects from VPROTECTED to GND
Put the PPTC in series with the power path so the protected branch's current passes through it. Littelfuse describes PPTCs as changing from low to high resistance rather than opening completely; resetting generally requires removing power and allowing cooling. Manufacturer PPTC guidance
Required support passives: None for the fuse itself. Select downstream regulator/IC decoupling and bulk capacitance from those devices' datasheets; there is no verified fuse-specific requirement for a 1 µF capacitor. Assess the resulting capacitor-charging inrush against the fuse's time-current response.
Voltage selection: A nominal 3.3 V or 5 V rail is a possible application only when the actual worst-case voltage and fault conditions remain within the listed rating. Do not use this 6 V-listed device on 9 V, 12 V, or higher-voltage USB-PD operation. USB use here concerns the power path only; this fuse does not establish CC negotiation, USB current entitlement, shielding, or data-line protection.
Current selection: Include maximum sustained load, startup pulses, ambient temperature, nearby heat sources, and available short-circuit current. A current-limited supply below the trip region may leave the PPTC conducting indefinitely rather than produce the response expected from an 8 A test.
Voltage-drop estimate: Engineering calculation using the listed, PDF-unverified R1max: at 1.00 A, Vdrop = I × R = 0.160 V and P = I² × R = 0.160 W. At 1.10 A, the same estimate gives 0.176 V and 0.194 W. These are illustrative recovered-resistance estimates, not guarantees of hot operating resistance or full-temperature continuous operation.
Recovery and testing: Test cold start, warm restart, normal load at maximum enclosure temperature, representative overloads, and cooldown/restart. Do not assume that simply removing the short restores operation immediately while power stays applied. Manufacturer PPTC guidance
No LED series-resistor calculation or connector CC-pin pull-down prescription applies to this component.
4. PCB Layout & Routing Guidelines
The following are engineering recommendations, not claimed manufacturer-specific dimensions:
Use the current PPTC land pattern. Confirm terminal geometry, body tolerance, solder mask, and stencil apertures before release. Exact Littelfuse pad dimensions and reflow profile remain unverified; a generic 0805 resistor footprint is not automatically approved.
Place near the power entry or branch origin. Keep the unprotected segment short and ensure every path powering the protected load passes through the PPTC; alternate/backfeed supplies can bypass it.
Size copper for both normal and pre-trip current. Choose trace width and vias from copper thickness, temperature-rise allowance, voltage-drop budget, and fault duration. No universal trace width is appropriate. Avoid narrow pad necks or thermal-relief spokes becoming the unintended fuse.
Control the thermal environment. Keep away from hot regulators and power resistors. Copper pours, thermal relief, airflow, enclosure temperature, and coatings affect heat flow and therefore trip behavior; validate on the actual assembly rather than assuming more copper is always beneficial. Temperature sensitivity and application testing are emphasized in the manufacturer selection guide.
Keep load decoupling at the load. Do not place a PPTC in a USB differential pair or other high-speed signal path. Differential-pair impedance/matching rules apply to the interface traces, not to this two-terminal power-protection device.
5. Common Pitfalls / Things to Watch Out For
Treating “1.1 A” as a precise current limit independent of temperature. The hold and trip specifications serve different purposes; overload response depends on temperature and current duration. Derating and actual-board validation are necessary, and the listed 100 ms response belongs to an 8 A test—not every overload.
Treating a tripped PPTC as an open-circuit safety disconnect. A PPTC limits current but continues to pass leakage current, and reset generally requires power removal and cooling. Use an appropriately rated fuse or disconnect architecture when complete interruption or safety isolation is required. The 0805L110WR's exact tripped leakage, reset time, and repeat-trip lifetime were not verified. Manufacturer PPTC guidance
6. Popular Alternatives & Equivalents
No unconditional drop-in replacement was verified. Both candidates below have a similar two-terminal protection function, but protection behavior and mechanical fit must be reviewed. Exact matches were not found in the Flux library; nearby search results were different MPNs and were deliberately not linked as equivalents.
Recheck higher trip current, slower trip response, larger recovered resistance, and clearance. Bel dimension C is 0.75–1.80 mm. Bel nominal recommended pad dimensions are P = 1.20 mm, S = 1.00 mm, W = 1.50 mm; consult the drawing to interpret the letters.
PDF-unverified candidate: manufacturer PDF search lead lists 0805, Ihold 1.10 A at 23°C, Itrip 2.20 A, Vmax 6 V, Imax 40 A, maximum trip time 0.30 s at 8 A, Rmin 0.060 Ω, R1max 0.210 Ω. Citation-backed lookup remained pending.
Provisional functional alternative only. Pin-number and exact footprint compatibility unverified.
Verify the exact -2 ordering suffix and current datasheet; do not substitute where available fault current exceeds its preliminary 40 A rating. Requalify trip timing, resistance, derating, and solder land pattern.
For JLCPCB-oriented sourcing, the Bel candidate has a JLCPCB listing, C5468859. A listing is not confirmation of current stock, process suitability, or a drop-in replacement.
7. Sourcing & Purchasing Guide
Table
Attribute
Details
Primary Distributors
Exact-part purchase listings were located at DigiKey, Mouser, Arrow, and LCSC, C468889. Availability and purchasing terms must be confirmed at checkout; distributor authorization should be checked against the manufacturer's current channel list.
Packaging Options
Factory tape-and-reel is indicated by the WR ordering code; distributor leads also show cut tape and Digi-Reel. Factory code interpretation and packaging details remain PDF-unverified.
Standard MOQ
Preliminary purchasing leads: 1 piece for DigiKey cut tape; 3,000 pieces for a full factory reel. Not confirmed from a directly retrieved DigiKey product page: verify the selected CT/TR option and order multiple before ordering. Factory reel quantity also remains PDF-unverified.
Sourcing Advice
Prefer franchised/authorized channels and traceable lots over anonymous marketplaces. Match the complete MPN, including WR; do not assume -A, HF, SL, TH, or other suffix variants are identical. Confirm the current datasheet, packing quantity, date/lot traceability, and moisture-handling requirements.
JLCPCB Assembly
LCSC lists the exact MPN as C468889; this does not independently establish JLCPCB assembly inventory or Basic/Extended classification. Confirm assembly-library availability and the submitted footprint before a PCBA order.
Price and Stock
No durable price, stock quantity, or lead-time promise is made. Live purchase listings change and must be checked for the selected quantity and packaging.
Littelfuse 0805L datasheet, LCSC-hosted manufacturer-document copy: preliminary search leads for derating, mechanics, and packaging; citation lookup remained pending. Document revision/date unresolved. The hosting filename's -A text is not proof that -A and unsuffixed parts are identical.
Bourns MF-PSMF Series datasheet: alternative candidate; PDF evidence lookup remained pending, so specifications and revision/date are not fully verified.
Purchasing sources
DigiKey, Mouser, Arrow, and LCSC exact-part listing links in Section 7, located through library distributor data; purchasing terms and current authorization require confirmation.
Before publishing as a fully verified guide: resolve the Littelfuse and Bourns PDF evidence, confirm temperature-table conditions and document revisions, check both land-pattern drawings, and directly confirm purchasing MOQ/packaging. No electrical, schematic, footprint, or layout changes were made to the part project.