B57235S0509M000 - 5Ω NTC Inrush Current Limiter | TDK
部品番号: B57235S0509M000 ✓ 生産中| 数量 | 単価 | 小計 |
|---|---|---|
| 1 | $0.65 | $0.65 |
| 10 | $0.55 | $5.50 |
| 100 | $0.42 | $42.00 |
| 500 | $0.33 | $165.00 |
| 1,000 | $0.27 | $270.00 |
B57235S0509M000 概要
An NTC (Negative Temperature Coefficient) inrush current limiter is a thermistor whose resistance falls as its body temperature rises. At the moment a large bulk capacitor bank or transformer primary is energized, the cold thermistor presents its full 5 Ω to the circuit, charging the capacitors gently and absorbing the worst of the charging spike. As inrush current flows, I²R self-heating drives the resistance down by an order of magnitude or more, leaving the part thermally stable at low ohmic loss during normal steady-state operation. The category sits within thermistors -> passive components -> circuit protection devices, and is one of the simplest and most economical soft-start methods for AC-DC and DC-DC converters.
Key features include a wide operating temperature window of -40 °C to +170 °C suitable for commercial and industrial environments, tinned copper leads with a kinked geometry for through-hole mounting, a flame-retardant coating rated 94 V-0, and an ICL max current rating of 4 A continuous (with 4.2 A as the steady-state maximum). The epoxy-coated disk dissipates inrush energy as heat during the first few line cycles and then settles to a low-resistance steady state so that operating losses are minimized.
Typical applications include input filtering for switch-mode power supplies, soft-start of large aluminum-electrolytic capacitor banks, protection of rectifier bridges and MOSFETs at turn-on, soft-start of motors and transformers, and as a coarse surge suppressor at the AC mains input. The 5 Ω cold resistance is well matched to 100-240 VAC class supplies charging 100 µF to 1000 µF bulk capacitance banks.
When designing with this part, verify that the steady-state RMS current after warm-up remains comfortably below the 4.2 A rating, otherwise the thermistor will not return to its low-R steady state. Place the device on the high-side of the AC line after the fuse so that the fuse clears if the thermistor shorts, and provide at least 10 mm of lead clearance to nearby hot components to avoid derating.
ドロップイン代替品: B57235S0509M000 — 同一パッケージでピン互換。PCBの作り直しが必要な異なるパッケージの部品は除外されています。
クイック比較ツール — 並列比較する代替部品を選択:
B57235S0479M000
✅ ドロップイン ⚠️ 仕様未検証📋 参考代替品（カタログ未掲載）
B57235S0609M000
✅ ドロップイン ⚠️ 仕様未検証📋 参考代替品（カタログ未掲載）
B57235S0500M000
✅ ドロップイン ⚠️ 仕様未検証📋 参考代替品（カタログ未掲載）
B57235S0220M000
✅ ドロップイン ⚠️ 仕様未検証📋 参考代替品（カタログ未掲載）
B57235S0100M000
✅ ドロップイン ⚠️ 仕様未検証📋 参考代替品（カタログ未掲載）
SL32 10015
✅ ドロップイン📋 参考代替品（カタログ未掲載）
NTC 5Ω 4A through-hole
✅ ドロップイン📋 参考代替品（カタログ未掲載）
B57235S0509M000 仕様
| Component Type | NTC Inrush Current Limiter (ICL) |
| Series | S 235 (B57235S) |
| Resistance @ 25 °C (R25) | 5.0 Ω |
| Resistance Tolerance | ±20% |
| Steady-State Max Current (Imax) | 4.2 A |
| ICL Rated Current | 4 A |
| 動作温度範囲 | -40 °C to +170 °C |
| Diameter | 9.50 mm (0.374 in) |
| Thickness | 5.5 mm |
| Lead Spacing | 5.00 mm (0.197 in) |
| Lead Style | Tinned copper wire, kinked, through-hole |
| Coating | Flame retardant 94 V-0 resin |
| 実装タイプ | Through Hole |
| Typical Application | Switch-mode power supplies |
| RoHS ステータス | Compliant (per TDK product page) |
B57235S0509M000 standard ピン配置ガイド
B57235S0509M000 (standard パッケージ) のピン配置。 ピン番号、機能、接続図はメーカーのデータシートで定義されています。正確なフットプリントとはんだ付けのガイドラインについては、データシートを参照してください。
詳細なピン配置データはありません: B57235S0509M000.
詳細は データシート をご参照ください。
主な用途
B57235S0509M000 の用途: 6 件s: Switch-Mode Power Supply Input Stage, AC-DC Converter Soft-Start for Bulk Capacitor Banks, Motor Soft-Start Protection, Rectifier Bridge and MOSFET Surge Protection, Industrial Control Power Input Conditioning, Welding Inverter and High-Power Tool Soft-Start.
Switch-Mode Power Supply Input Stage
The B57235S0509M000 is the standard NTC inrush limiter placed in series with the AC line of 100-500 W switch-mode power supplies. At turn-on, its cold 5 Ω impedance slows the charging of the 1-4 µF X-capacitor and the bulk electrolytic bank, holding the bridge-rectifier and PFC MOSFET within their safe repetitive-pulse ratings. Once steady-state is reached, the device self-heats and drops to a fraction of an ohm, minimizing wasted power - the typical 4.2 A continuous rating comfortably covers SMPS idle-to-full-load currents below ~3 A continuous.
おすすめ
AC-DC Converter Soft-Start for Bulk Capacitor Banks
Large aluminum-electrolytic bulk capacitors in 400 V-class converters draw huge non-repetitive surge currents at turn-on. The B57235S0509M000, with its 5 Ω ±20% cold resistance and 9.5 mm coated-disk body that absorbs the joules, limits that surge to a level that the upstream fuse and bridge rectifier can survive. Per the TDK datasheet, the device is rated for switch-mode power supply environments and integrates cleanly with 100-1000 µF bulk banks on universal-input (100-240 VAC) converters.
おすすめ
Motor Soft-Start Protection
Single-phase induction motors and small universal motors present a near-short at standstill, drawing locked-rotor currents 5-10× running current. The B57235S0509M000 placed in series with the AC mains pre-empts that locked-rotor surge and ramps the motor into running current over 1-3 seconds as its thermistor body warms. The 4 A steady-state rating suits fractional-horsepower motors up to ~300 W, and the 5 mm lead spacing accommodates through-hole motor-control PCB layouts.
おすすめ
Rectifier Bridge and MOSFET Surge Protection
The leading-edge current spike at converter turn-on can exceed 100 A for tens of microseconds, enough to damage rectifier bridges and the drain of main switching MOSFETs. The B57235S0509M000, mounted between the AC line and the bridge, attenuates that spike into a slow ramp that the semiconductor junctions can absorb. The 4.2 A steady-state rating ensures the thermistor runs cool during normal operation and does not introduce significant losses at full load.
おすすめ
Industrial Control Power Input Conditioning
Industrial PLCs, motor drives and process controllers running off 24 VDC or 48 VDC rails still see inrush when downstream bulk capacitance charges. The B57235S0509M000 can be inserted on the DC bus (despite its AC-rated marketing) to limit turn-on current and protect DC-side hot-swap controllers. The -40 °C to +170 °C operating window tolerates unheated cabinets and hot enclosure interiors, while the flame-retardant 94 V-0 coating satisfies industrial safety requirements.
おすすめ
Welding Inverter and High-Power Tool Soft-Start
Welding inverters and high-power corded tools (impact wrenches, chainsaws, circular saws) switch large capacitor banks and motor windings that draw huge inrush pulses. The B57235S0509M000 used as the AC-side pre-charge element ramps the system into running state over 1-2 seconds, protecting the trigger switch, brush holders, and PFC stage. Its 4 A steady-state limit suits tools in the 800-1500 W class when paired with downstream soft-start electronics.
おすすめ
おすすめ製品の概要
エンジニアリング参考データ: B57235S0509M000 — 比較、設計ガイダンス、コンプライアンス情報。
選定ガイド
代替品との比較
| パラメータ | この製品 | B57235S0479M000 | B57235S0609M000 | B57235S0500M000 | Amwei 5Ω 4A compatible |
|---|---|---|---|---|---|
| Brand | TDK (EPCOS legacy) | TDK | TDK | TDK | Amwei |
| Package / Lead Spacing | 9.5 mm disk / 5 mm lead pitch (through-hole) | 9.5 mm disk / 5 mm pitch - same | 9.5 mm disk / 5 mm pitch - same | 9.5 mm disk / 5 mm pitch - same | 9.5 mm disk / 5 mm pitch - same |
| R25 Cold Resistance | 5.0 Ω ±20% | 4.7 Ω ±20% | 6.0 Ω ±20% | 5.0 Ω ±20% | 5.0 Ω ±20% |
| Steady-State Max Current | 4.2 A | 4 A (typical) | 4 A (typical) | 4.2 A | 4 A |
| Operating Temperature | -40 °C to +170 °C | -40 °C to +170 °C | -40 °C to +170 °C | -40 °C to +170 °C | -40 °C to +170 °C |
| Coating / Flame Rating | Epoxy, 94 V-0 | Epoxy, 94 V-0 | Epoxy, 94 V-0 | Epoxy, 94 V-0 | Resin coated, 94 V-0 |
| Lead Style | Tinned copper, kinked, through-hole | Tinned copper, kinked, through-hole | Tinned copper, kinked, through-hole | Tinned copper, kinked, through-hole | Tinned copper, through-hole |
| RoHS Status | Compliant (with ELV exemption per JEDEC JESD97) | Compliant (with ELV exemption) | Compliant (with ELV exemption) | Compliant (with ELV exemption) | Compliant |
主な差別化要因
- Tighter cold resistance vs higher-Ω family members （vs B57235S0100M000 (10 Ω))
- Smaller disk vs 32 mm-class ICLs （vs Ametherm SL32 10015)
- Stable 5 Ω ±20% tolerance from a tier-one passive manufacturer （vs Amwei compatible 5 Ω 4 A ICL)
設計ノート
The B57235S0509M000 dissipates its 5 Ω cold resistance as I²R heat during the first 0.5-2 seconds of turn-on, then settles to a much lower steady-state resistance once self-heated. Per TDK documentation, the device body can reach 170 °C in extreme fault conditions - keep at least 10 mm clearance to plastic enclosures, wire insulation, and other heat-sensitive components, and provide a copper pour or free-air ventilation around the disk to carry heat away during repeated inrush events.
Place the B57235S0509M000 on the high-side AC line after the input fuse and before the bridge rectifier so that the fuse clears if the thermistor ever fails short. Per the TDK datasheet, the kinked tinned-copper leads fit a 5 mm lead-pitch through-hole pattern; reserve 13 mm × 10 mm of board real estate for the disk plus strain relief. Maintain at least 8 mm of creepage between the thermistor body and any adjacent primary-side traces to satisfy IEC 60950 / IEC 62368 clearance for reinforced insulation.
Estimated: At a steady-state line current of 3 A through a fully-warmed B57235S0509M000 (warm R ≈ 0.2 Ω typical), the device dissipates roughly 1.8 W and the disk temperature rises ~60-80 °C above ambient. If your design pushes the steady-state current close to the 4.2 A maximum, the thermistor will not fully transition to its low-resistance state and you will see unacceptable conduction loss. Always measure worst-case RMS line current at full load and derate by at least 20% to ensure the device thermally stabilizes.
コンプライアンス情報
RoHS compliant per TDK product page. TTI distributor listing notes the Pb content of the termination material exceeds 0.1% by weight, referenced under JEDEC JESD97 paragraph 3.5 and EU Commission Decision 2002/525/EC Annex II (ELV Directive exemption). Confirm with compliance team whether the exemption applies to your end application. AEC-Q100 not applicable (passive component).
