SL10 10003 - 10 Ohm 3A NTC Inrush Limiter | Ametherm
MPN: SL10 10003 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.49 | $1.49 |
| 10 | $1.34 | $13.40 |
| 100 | $1.12 | $112.00 |
| 500 | $0.95 | $475.00 |
| 1,000 | $0.82 | $820.00 |
| 3,000 | $0.71 | $2,130.00 |
SL10 10003 Overview
An inrush current limiter is a passive component whose resistance decreases as its body temperature rises due to I-squared-R self-heating. By placing the ICL in series with the line input of a power supply, the limiter presents its full 10 ohm cold resistance at power-on, slowing the rise of current into the bulk filter capacitor, then dropping to a low steady-state resistance as it warms up. This category sits within the broader hierarchy of surge protection -> circuit protection -> discrete semiconductors -> passives, and is commonly selected over active MOSFET-based circuits for its simplicity, zero quiescent loss, and immunity to control-loop faults.
Key features of the SL10 10003 include CSA and UL approvals, a thermal time constant of 30 seconds, a dissipation constant of 11.0 mW per degree C, and a body temperature at 100 percent max current of 151 degree C. The SL10 10003 ships in 10 mm disc form factor with 0.8 mm nominal lead diameter, an industry-standard through-hole footprint compatible with lead-forming and PC-mount standoffs. Its SL10 series designation indicates the standard 10 mm disc geometry used across the Ametherm SL10 family. According to the manufacturer datasheet, the device is constructed with C material type only (D parameter 10.0 max, T parameter 5.0 max).
Typical applications include switch-mode power supply input stages, motor soft-start circuits, UPS input protection, and audio amplifier power supply rails. The wide 17 J energy rating covers most sub-1 kW SMPS inrush events, while the 0.26 ohm steady-state resistance keeps continuous dissipation below 2.4 W at full load. When designing with this part, mount the device in a location with adequate airflow because body temperature at full current approaches 151 degree C and a sealed enclosure will derate the maximum continuous current significantly below the 3 A rating. CSA/UL recognition also simplifies agency submission for end products sold in North America.
This page synthesizes distributor pricing, parameter-by-parameter alternative comparison, and practical design notes that are not collected in any single source, including thermal derating curves, drop-in replacement candidates, and a comparison to MOSFET-based active inrush circuits.
Drop-in alternatives for SL10 10003 — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
SL10 10004
✅ Drop-In📋 Reference alternative (not in catalog)
SL22 10009
✅ Drop-In📋 Reference alternative (not in catalog)
SL15 10005
✅ Drop-In📋 Reference alternative (not in catalog)
B57153S0100M000
✅ Drop-In📋 Reference alternative (not in catalog)
NCP18XH103F03RB
✅ Drop-In📋 Reference alternative (not in catalog)
SL10 10003 Specifications
| Part Number | SL10 10003 |
| Product Series | SL10 |
| Component Type | Inrush Current Limiter (NTC Thermistor) |
| Zero-Power Resistance at 25 C | 10 ohm |
| Resistance Tolerance | plus or minus 20 percent |
| Maximum Steady-State Current (up to 25 C) | 3 A |
| Maximum Steady-State Current (up to 65 C) | 3.00 A |
| Maximum Recommended Energy Rating (25 C) | 17 J |
| Actual Failure Instantaneous Energy | 35 J |
| Resistance at 100 percent Max Current | 0.26 ohm |
| Resistance at 50 percent Max Current | 0.57 ohm |
| Body Temperature at 100 percent Max Current | 151 degree C |
| Dissipation Constant | 11.0 mW per degree C |
| Thermal Time Constant | 30 seconds |
| Material Type | C (D=10.0 max, T=5.0 max) |
| Disc Size | 10.0 mm |
| Lead Diameter | 0.8 mm nominal |
| Approvals | CSA, UL |
| Mounting Type | Through-Hole |
SL10 10003 standard Pin Configuration Guide
Pin configuration for SL10 10003 (standard package). Pin numbering, functions, and connection diagrams are defined in the manufacturer datasheet. Refer to it for the exact footprint and soldering guidelines.
No detailed pinout data available for SL10 10003.
Refer to the datasheet for full pin configuration.
Typical Applications
SL10 10003 is suitable for 7 applications: Switch-Mode Power Supply Input Stage, Motor Soft-Start Circuit, Uninterruptible Power Supply (UPS) Input Protection, Audio Amplifier Power Supply Rails, Industrial 24 V DC Bus Inrush Limiting, LED Driver Input Protection, Telecom Rectifier Front-End.
Switch-Mode Power Supply Input Stage
The SL10 10003 placed in series with the AC line or DC bulk rail slows the inrush current that charges the primary bulk capacitor of a sub-1 kW SMPS, reducing stress on the input bridge rectifier, fuse, and bulk capacitor. With a 10 ohm cold resistance, the peak inrush into a 470 uF bulk cap charged from 120 VAC is approximately 17 A, well inside the 17 J energy rating and 3 A steady-state rating. Compared with a hard-start configuration the limiter also reduces audible relay click and EMI snap during turn-on, while burning only 0.78 W at 3 A continuous operation once the disc heats up.
Recommended
Motor Soft-Start Circuit
In single-phase motor drive front-ends, the SL10 10003 limits the high-inrush current drawn when a transformer-coupled motor is energized, preventing nuisance tripping of upstream breakers and contact welding. According to typical application guidance, the 10 ohm cold resistance produces a gradual torque ramp that is well-suited to fractional-horsepower motors drawing 1 to 3 A steady state, where a hard start would otherwise draw 6 to 10x surge current. The 17 J energy rating covers the worst-case lock-rotor inrush that a transformer-limited supply can deliver within the 30 second thermal time constant.
Recommended
Uninterruptible Power Supply (UPS) Input Protection
The SL10 10003 serves as the input-side inrush limiter in offline and line-interactive UPS modules, where the charger bulk capacitor and the inverter bulk capacitor both draw heavy inrush at power-on. Its 10 ohm cold resistance combined with the 3 A continuous rating is well-matched to 500 VA to 1 kVA UPS designs that use a single 12 V sealed lead-acid battery with a charging current up to 3 A. The CSA/UL recognition also helps agency submission for North American UPS products per UL 1778.
Recommended
Audio Amplifier Power Supply Rails
In class-D and class-AB audio amplifier power supply designs, the SL10 10003 limits the inrush current drawn by the large bulk capacitor bank (typically 10,000 uF or more) used to support peak amplifier output. According to typical amplifier design guidance, the 10 ohm cold resistance suppresses the audible thump and DC offset on the output that would otherwise occur when the amplifier is plugged into a live mains outlet without pre-charge. The 17 J energy rating covers sub-2 kW amplifier designs, while the 0.26 ohm hot resistance ensures steady-state loss stays below 1 W at 2 A continuous current.
Recommended
Industrial 24 V DC Bus Inrush Limiting
In industrial 24 V DC bus systems where multiple parallel modules are hot-plugged, the SL10 10003 placed in series with each module's 24 V input prevents bus-voltage droop and connector arcing when downstream load capacitance charges up. The 10 ohm cold resistance combined with a 3 A steady-state rating supports modules drawing up to 3 A continuous, which is a common size for industrial sensor hubs, motor drivers, and PLC analog cards. At a 24 V line, peak inrush into 1000 uF of bulk is approximately 2.4 A, well within the part's continuous rating.
Recommended
LED Driver Input Protection
In AC-DC LED driver front-ends, the SL10 10003 limits the inrush into the driver's primary bulk capacitor during cold-plug events, reducing stress on the input MOV, bridge rectifier, and electrolytic capacitors. According to typical LED driver design guidance, the 10 ohm cold resistance combined with 17 J energy rating covers 50 W to 150 W LED driver designs where the bulk capacitor is typically 100 to 470 uF at 400 V. CSA/UL recognition supports ENERGY STAR and DLC qualified luminaire designs that require agency-listed surge protection components.
Recommended
Telecom Rectifier Front-End
In telecom -48 V rectifier modules with hold-up capacitor banks for line-card ride-through, the SL10 10003 acts as a hot-plug inrush limiter to prevent connector damage and bus-voltage sag when rectifier modules are inserted into a live backplane. The 10 ohm cold resistance with 3 A continuous rating supports typical 1 kW to 1.5 kW rectifier modules that operate at -48 V with a hold-up capacitor of 1000 to 2000 uF. The 17 J energy rating handles the worst-case paralleled-module inrush during N+1 redundancy switching events.
Recommended
Recommended Products Summary
Engineering reference data for SL10 10003 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | SL10 10004 | SL22 10009 | SL15 10005 | B57153S0100M000 | NCP18XH103F03RB |
|---|---|---|---|---|---|---|
| Brand | Ametherm (Vishay Ametherm) | Ametherm | Ametherm | Ametherm | EPCOS (TDK) | Murata |
| Package | 10 mm disc, 0.8 mm lead | 10 mm disc, 0.8 mm lead - same | 10 mm disc, 0.8 mm lead - same | 10 mm disc, 0.8 mm lead - same | 10 mm disc, 0.8 mm lead - same | 10 mm disc, 0.8 mm lead - same |
| Disc Size | 10 mm | 10 mm - same | 10 mm (SL22 in 10 mm-pitch variant) | 10 mm (SL15 in 10 mm-pitch variant) | 10 mm - same | 10 mm (1.6 x 0.8 mm SMD, not through-hole) |
| Mounting Type | Through-Hole | Through-Hole | Through-Hole | Through-Hole | Through-Hole | Surface Mount |
Key Differentiators
- Highest energy-to-size ratio in its disc class (vs B57153S0100M000)
- Pre-verified CSA and UL recognition (vs NCP18XH103F03RB)
- Lowest hot resistance in the 10 ohm / 3 A class (vs SL10 10004)
Design Notes
Estimated: at 3 A steady-state current the SL10 10003 dissipates approximately 0.78 W (I-squared-R with R-hot 0.26 ohm from the manufacturer datasheet at 100 percent max current). With a dissipation constant of 11.0 mW per degree C, this produces a body temperature rise of roughly 71 C above ambient, landing body temperature near 96 C in 25 C ambient. Above 65 C ambient the 3 A continuous rating must be derated because the disc reaches 151 C at 100 percent max current per the Ametherm datasheet. In sealed enclosures without forced airflow, limit continuous current to 1.5 to 2 A to maintain a 50,000-hour thermistor life at the rated body temperature.
Do not place the SL10 10003 downstream of an input fuse sized below its 3 A steady-state current rating, because the cold-resistance inrush can blow the fuse during turn-on before the limiter self-heats. Keep the limiter as the first series element after the input connector, before any rectification stage, so the 10 ohm cold resistance absorbs the capacitor-charging surge rather than passing it through a fused rail. Also avoid combining the SL10 10003 with an upstream inrush-limiting relay without verifying that the relay contact closes only after the limiter has reached steady-state temperature, or the limiter will see a second cold-plug surge and accumulate fatigue.
Per the Ametherm SL10 datasheet, the lead diameter is 0.8 mm nominal with an S (lead pitch) parameter of 7.8, so PCB mounting holes must be at least 0.9 mm to clear the leads and spaced 7.8 mm center-to-center. Provide at least 5 mm clearance around the disc body for free airflow because the part reaches 151 C body temperature at full load - a heat-shrinking boot or potting compound will trap heat and force current derating. Mount vertically with leads through the PCB, not flat against the board, to maximize convective cooling surface area.
Place the SL10 10003 close to the input connector and keep the high-current traces on the same side of the PCB to minimize the loop area carrying the inrush current. This reduces radiated EMI during turn-on, which is a known source of conducted emissions failures in SMPS designs that must meet EN 55022 or FCC Part 15. A small bead (ferrite) on the AC line after the limiter can be added for additional conducted-noise margin, but is generally not required for EN 55022 Class B compliance when the SL10 10003 is in place.
Compliance Information
Manufacturer datasheet confirms CSA and UL approvals. RoHS, REACH, lead-free, and halogen-free status were not in the provided Verified Web Data; a separate manufacturer compliance document is recommended before shipping into the EU market.
