SS24T3G - 40V 2A SMB Schottky Rectifier | onsemi
料号： SS24T3G ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $0.62 | $0.62 |
| 10 | $0.55 | $5.50 |
| 100 | $0.41 | $41.00 |
| 500 | $0.32 | $160.00 |
| 1,000 | $0.26 | $260.00 |
| 2,500 | $0.22 | $550.00 |
SS24T3G 概述
A Schottky diode is a unipolar semiconductor rectifier formed by a metal-semiconductor junction rather than a PN junction, which eliminates minority-carrier charge storage and enables switching speeds orders of magnitude faster than conventional silicon rectifiers. Within the broader taxonomy, the SS24T3G sits under: Schottky diode -> rectifier diode -> discrete semiconductor -> electronic component. Compared to standard recovery rectifiers (1N400x series) and ultrafast recovery diodes, Schottky rectifiers trade higher reverse leakage for lower forward voltage and negligible reverse-recovery time, making them the preferred choice for low-voltage, high-frequency power conversion.
Key features include a guard ring for transient protection, a low-profile SMB package suitable for automated assembly, and a moisture sensitivity level of MSL 1 (unlimited floor life per JEDEC J-STD-020). The oxide-passivated epitaxial construction provides long-term stability of forward voltage drop and reverse leakage. The metal-overlay contact geometry yields a robust die-to-package interconnect that survives thermal cycling typical of SMPS environments.
Architecturally, the SS24T3G uses a single Schottky barrier die encapsulated in a moulded epoxy SMB body with a copper-lead frame and a matte-tin plated finish for lead-free reflow compatibility. The asymmetric minority-carrier-free conduction mechanism means switching loss is dominated by capacitive charge (Qc) rather than reverse recovery, enabling efficient operation at switching frequencies from tens to hundreds of kHz.
Typical applications include low-voltage, high-frequency switching power supplies as free-wheeling diodes, polarity-protection diodes in DC distribution rails, and OR-ing diodes in redundant power architectures. It is well-suited as the output rectifier on a 12 V or 24 V buck-derived rail.
When designing with this part, observe the SMB power-package land-pattern recommendation and respect the derating curve above 25 C ambient. For high-frequency operation, the capacitive charge Qc dominates switching loss and should be accounted for in efficiency analysis.
This page synthesizes distributor pricing, drop-in alternatives in the same SMB footprint, and practical thermal and layout design notes not found in the manufacturer datasheet alone.
直接替换替代料： SS24T3G ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
快速对比工具——选择替代料号进行并排对比：
NRVBSS24T3G
✅ 直接替换📋 参考替代料（不在目录中）
SS22T3G
✅ 直接替换📋 参考替代料（不在目录中）
SBRSS24T3G
✅ 直接替换📋 参考替代料（不在目录中）
B240-13-F
✅ 直接替换📋 参考替代料（不在目录中）
SS24-E3/52
✅ 直接替换📋 参考替代料（不在目录中）
MBRS240LT3G
✅ 直接替换📋 参考替代料（不在目录中）
SS24T3G 最大额定值与电气特性
| Manufacturer | onsemi |
| Diode Type | Schottky Barrier Rectifier |
| 封装 | SMB (DO-214AA, surface mount) |
| Repetitive Peak Reverse Voltage (VRRM) | 40 V |
| Average Rectified Forward Current (IF(AV)) | 2 A |
| 工作结温范围 | -55 C to +150 C (per onsemi SS24 family datasheet family convention) |
| Storage Temperature Range | -55 C to +150 C |
| 安装类型 | Surface Mount |
| Packaging | Tape & Reel (T3 suffix) |
| Standard Reel Quantity | 2,500 pieces |
| MSL (Moisture Sensitivity Level) | MSL 1 (Unlimited floor life) |
| RoHS 状态 | Compliant (per PartGenie ROHS3 Compliant) |
| REACH Status | Unaffected (per PartGenie) |
| Lead Finish | Matte-Tin (Pb-free) |
| Construction | Epitaxial with oxide passivation and metal overlay contact |
SS24T3G 引脚配置
| 引脚 1 | Cathode — Cathode terminal (marked with polarity band on SMB case) |
| 引脚 2 | Anode — Anode terminal |
典型应用
SS24T3G 适用于 6 应用s: Switching Power Supply Freewheeling Diode, DC Polarity-Protection Diode, OR-ing Diode for Redundant Power, Buck Converter Output Rectifier, Solar Charge Controller Blocking Diode, Automotive 12 V Load-Dump Protection (with TVS).
Switching Power Supply Freewheeling Diode
The SS24T3G's 40 V VRRM and 2 A continuous forward current make it a strong fit as a freewheeling (commutation) diode across the low-side switch or output rectifier of a low-voltage buck, boost, or flyback converter. With Schottky barrier construction, the SS24T3G exhibits negligible reverse-recovery charge (Qrr) compared to ultrafast PN rectifiers, eliminating the switching loss penalty that limits high-frequency SMPS efficiency. Placed in parallel with an inductor or synchronous rectifier body diode, it carries the 100 kHz to 1 MHz switching ripple with low forward drop, holding conduction loss to roughly VF x IF. For 12 V input to 3.3 V/5 V output rails, the SS24T3G is comfortably rated above the worst-case reverse voltage and continuous current. Designers should size the copper pad area to keep the junction temperature below 125 C at full load, using the SMB thermal resistance (typically 30 to 50 C/W on a 1 oz FR-4 board). Compared to a 1N5404 axial diode, the SMB footprint saves board area and enables automated assembly, while the Schottky drop (0.5 V typical) cuts rectifier loss by 30 to 50%.
推荐
DC Polarity-Protection Diode
The SS24T3G is ideal for polarity-protection diodes in series with a DC input rail where reverse-battery or mis-wiring would otherwise damage downstream circuits. At 40 V VRRM, it tolerates 12 V and 24 V automotive or industrial bus transients with margin, while its 2 A continuous rating covers typical point-of-load distribution rails. As a Schottky rectifier, the SS24T3G adds only about 0.5 V of forward drop at full load, which is often acceptable for sub-5 V rails and acceptable when the upstream fuse or hot-swap controller handles the inrush. Compared to a P-channel MOSFET polarity switch, the SS24T3G avoids the gate-drive complexity and offers true passivity, blocking reverse current automatically without software control. Place the SS24T3G near the input connector with a TVS clamp (e.g., SMAJ33CA) in parallel for transient suppression. Designers should verify that the worst-case DC reverse voltage (including load-dump transients) does not exceed 32 V (80% of VRRM) for reliable continuous operation. Compared to an SS34 (3 A, 40 V) Schottky, the SS24T3G is the lower-current sibling in the same family.
推荐
OR-ing Diode for Redundant Power
The SS24T3G serves as an OR-ing diode in redundant power architectures, where two independent DC sources feed a common load and the higher-voltage source dominates. With 40 V VRRM and 2 A rating, it handles 12 V or 24 V redundant rail combinations with adequate margin, and its low forward drop minimizes the loss budget when both sources share current during transitions. Schottky construction prevents the diode from becoming a reverse-charge pump that would destabilize the upstream regulators during power-source switchover. The SMB footprint is identical to the more common SS34 (3 A variant), enabling PCB reuse between 2 A and 3 A designs by simple BOM-tariff. For higher-current OR-ing, designers typically migrate to a P-channel MOSFET OR-ing controller (e.g., LTC435x family); the SS24T3G remains preferred for sub-2 A sub-100 W designs where simplicity wins. Estimate per-diode loss at 1 V worst-case forward drop and 2 A full load equals 2 W continuous, requiring a copper area that holds Tj below 125 C. Compared to a SS220 (20 V variant), the SS24T3G adds 20 V of headroom for inductive kick protection during load switch-off.
推荐
Buck Converter Output Rectifier
The SS24T3G is widely used as the output rectifier in non-synchronous buck converters operating from 12 V or 24 V inputs to 3.3 V, 5 V, or 12 V outputs. At 2 A average current and 40 V reverse voltage, it covers the majority of point-of-load conversion scenarios in industrial and consumer systems. The Schottky barrier yields a forward drop around 0.5 V, and the absence of minority-carrier storage means no reverse-recovery spike on the switch node, simplifying snubber design and reducing EMI compared to ultrafast PN rectifiers. Placed in the classic buck topology (catch diode position), the SS24T3G conducts during the switch-off phase, transferring inductor current to the load with minimal voltage loss. For synchronous-replacement upgrades, a P-channel MOSFET (e.g., SI2333DDS) halves the conduction loss; the SS24T3G remains the cost-effective default. Compared to the 1N5822 (3 A Schottky in axial package), the SS24T3G trades 1 A of current capacity for an order-of-magnitude smaller footprint and better thermal coupling. Designers should verify the peak inverse voltage (VIN + Vripple) does not exceed 32 V continuous, and use the published IF-VF curve to estimate conduction loss at the operating duty cycle.
推荐
Solar Charge Controller Blocking Diode
The SS24T3G is well-suited as a blocking diode between a photovoltaic panel and a battery in small-scale solar charge controllers. Its 40 V VRRM accommodates open-circuit PV voltages up to about 30 V (24 V nominal panel), and its 2 A rating handles sub-50 W charging applications. As a Schottky rectifier, the SS24T3G drops only about 0.5 V, preserving charging efficiency versus a 1N4001 (1 V drop), and its low reverse leakage minimizes nightly battery drain through the panel array. In a series-string topology with multiple panels, place one SS24T3G per string to prevent reverse current from shaded panels. Designers should add a TVS clamp (e.g., SMBJ30A) in parallel for lightning-induced transient protection and a heatsink copper pour for continuous sun conditions. Compared to the MBR1045 (10 A/45 V Schottky), the SS24T3G trades current capacity for a smaller, lower-cost solution appropriate to sub-100 W off-grid solar installations. Estimate the worst-case forward loss at peak charge current and verify that junction temperature stays below 100 C in the controller enclosure.
推荐
Automotive 12 V Load-Dump Protection (with TVS)
The SS24T3G's 40 V VRRM is well above the steady-state 12 V automotive bus voltage (8 to 16 V), and the AEC-Q101-qualified NRVBSS24T3G sibling in the same SMB footprint is the automotive-grade alternative for harsher environments. Used in series with a downstream load as a reverse-polarity blocker, the SS24T3G prevents damage during jump-start and reverse-battery events. A parallel TVS (e.g., SMBJ16A) clamps load-dump transients up to the SS24T3G's 40 V limit. Designers must derate to 32 V continuous for hot automotive environments and use the NRVBSS24T3G variant for underhood applications requiring AEC-Q101. Compared to a P-channel MOSFET reverse-blocker, the SS24T3G is simpler and cheaper but adds the forward-conduction penalty of about 0.5 V at full load. The SMB footprint matches common automotive-grade transient suppressors (SMAJ/SMBJ series), enabling co-location on the same copper pour.
推荐
推荐产品汇总
工程参考数据： SS24T3G ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | NRVBSS24T3G | SS22T3G | SBRSS24T3G | B240-13-F | SS24-E3/52 | MBRS240LT3G |
|---|---|---|---|---|---|---|---|
| Package | SMB (DO-214AA) | SMB (DO-214AA) - same | SMB (DO-214AA) - same | SMB (DO-214AA) - same | SMB (DO-214AA) - same | SMB (DO-214AA) - same | SMB (DO-214AA) - same |
| Brand | onsemi | onsemi (same-brand) | onsemi (same-brand) | onsemi (same-brand) | Diodes Incorporated (cross-brand) | Vishay Intertechnology (cross-brand) | onsemi (same-brand) |
| VRRM (Peak Reverse Voltage) | 40 V | 40 V | 20 V | 40 V | 40 V | 40 V | 40 V |
| IF(AV) (Average Forward Current) | 2 A | 2 A | 2 A | 2 A | 2 A | 2 A | 2 A |
| Diode Technology | Schottky Barrier | Schottky Barrier | Schottky Barrier | SBR (Super Barrier Rectifier) | Schottky Barrier | Schottky Barrier | Schottky Barrier |
| Automotive Qualification | No (commercial) | Yes (AEC-Q101) | No | No | No | No | No |
| Reel Quantity | 2,500 (T3) | 2,500 (T3) | 2,500 (T3) | 2,500 (T3) | 3,000 (13-F) | 850 (E3/52) | 2,500 (T3) |
| RoHS / Lead-Free | Yes / Yes | Yes / Yes | Yes / Yes | Yes / Yes | Yes / Yes | Yes / Yes | Yes / Yes |
| MSL | MSL 1 | MSL 1 | MSL 1 | MSL 1 | MSL 1 | MSL 1 | MSL 1 |
关键差异点
- Schottky barrier construction with metal overlay contact （对比 SBRSS24T3G)
- Commercial-grade qualification (vs automotive sibling) （对比 NRVBSS24T3G)
- 40 V rating vs 20 V sibling （对比 SS22T3G)
设计说明
Estimated: At full 2 A forward current, the SS24T3G dissipates approximately 1 W (0.5 V VF x 2 A). With the SMB package thermal resistance of approximately 30 C/W on a 1 oz FR-4 board with minimal copper, junction temperature rise is approximately 30 C above ambient. Increase copper pour to 1 square inch (per onsemi SS24 family recommendation) to reduce thermal resistance toward 15 C/W and improve current handling above 25 C ambient. Provide adequate copper area or forced-air cooling for continuous operation above 1.5 A in enclosed industrial enclosures.
Use the standard DO-214AA (SMB) land pattern with cathode polarity band matching the PCB silkscreen. Ensure the cathode thermal pad (if present in the recommended footprint) is soldered to a copper pour for heat spreading. Keep the SS24T3G away from sensitive analog traces to minimize conducted and radiated switching noise; route high-current loops tightly. For high-frequency SMPS applications, minimize the loop area between the SS24T3G and the switching node to reduce parasitic inductance and ringing on the switch node.
Do not exceed the 40 V VRRM rating under any operating condition, including inductive kick from a freewheeling inductor or transformer. For reverse-voltage transients above 32 V continuous, add a TVS clamp (e.g., SMBJ33A) in parallel. Verify the polarity orientation (cathode band) against the PCB silkscreen before reflow, since SMB packages are easily reversed during manual assembly. The forward voltage drop increases with temperature (positive temperature coefficient for Schottky), which actually aids parallel-diode current sharing but penalizes hot-spot reliability - derate current at elevated ambient.
合规信息
RoHS3 compliant and REACH unaffected per PartGenie (October 2026). MSL 1 (unlimited floor life) per JEDEC J-STD-020. AEC-Q101 automotive qualification is available on the NRVBSS24T3G sibling in the same SMB package. Matte-tin lead finish supports lead-free reflow profiles up to 260 C peak per JEDEC J-STD-020.
