BSS126H6327XTSA2 - 600V N-Ch Depletion MOSFET SOT-23 | Infineon
料号： BSS126H6327XTSA2 ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $0.78 | $0.78 |
| 10 | $0.65 | $6.50 |
| 100 | $0.48 | $48.00 |
| 500 | $0.39 | $195.00 |
| 1,000 | $0.32 | $320.00 |
BSS126H6327XTSA2 概述
A depletion-mode MOSFET is a field-effect transistor whose channel is physically present at fabrication; conduction is maximum when VGS = 0 and the channel is progressively pinched off as VGS is driven more negative (for an N-channel device). This category sits within the broader MOSFET (Metal-Oxide Semiconductor Field-Effect Transistor) family, which in turn belongs to power management and discrete semiconductors. Depletion-mode parts are rare in modern designs but are valued for circuits where the device must conduct before any control voltage is established, such as startup bleeding in offline flyback converters.
Key features of the BSS126H6327XTSA2 include the 600 V drain-source breakdown voltage that gives significant headroom for offline 120/230 VAC-derived rails, a low 21 mA continuous drain rating suitable for low-current auxiliary paths, and Infineon's SIPMOS process which combines vertical DMOS power-device ruggedness with small-signal SOT-23 packaging. The part operates as a constant-current source when biased with an external resistor, and as a high-side or low-side switch when the gate is driven negative relative to the source.
Typical applications include power-supply startup assist (providing initial bias to a controller before the auxiliary winding takes over), over-voltage protection clamps, in-rush current limiters inserted in series with downstream rails, and offline voltage references where the device establishes a defined current into a Zener diode. Its normally-on behavior also makes it useful for fail-safe circuits that must default to a conductive state.
When designing with the BSS126H6327XTSA2, treat the gate as a control input that requires negative bias to turn the device fully off; leaving the gate open is acceptable for many 'normally-on' topologies but ESD handling on the gate node must follow standard SOT-23 precautions. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found on any single manufacturer or distributor page.
直接替换替代料： BSS126H6327XTSA2 ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
本系列中的变体
可与以下型号直接替换的同系列型号： BSS126H6327XTSA2 （相同外形与封装尺寸） ——差异在于 Continuous Drain Current (ID), FET Type, Part Number, Package, RoHS Status.
快速对比工具——选择替代料号进行并排对比：
BSS126H6906XTSA1
✅ 直接替换📋 参考替代料（不在目录中）
BSS119NH6327XTSA1
✅ 直接替换✓ 有现货
$0.12 / 个
查看数据手册 →BSS127H6327XTSA2
✅ 直接替换✓ 有现货
$0.032 / 个
查看数据手册 →BSS123NH6327XTSA1
✅ 直接替换✓ 有现货
$0.085 / 个
查看数据手册 →BSS127S-7
✅ 直接替换📋 参考替代料（不在目录中）
BSS84PH6327XTSA2
✅ 直接替换✓ 有现货
$0.1 / 个
查看数据手册 →BSS126H6327XTSA2 最大额定值与电气特性
| FET Type | N-Channel Depletion Mode |
| Drain-Source Voltage (VDS) Max | 600 V |
| Continuous Drain Current (ID) at Ta | 21 mA |
| Power Dissipation (PD) at Ta | 500 mW |
| On-Resistance (RDS(on)) Max | 500 ohm (typical for depletion-mode) |
| Technology | SIPMOS (DMOS) |
| 封装 | SOT-23-3 (PG-SOT23) |
| 安装类型 | Surface Mount |
| 工作温度范围 | -55C to +150C (junction, typical) |
| 引脚数量 | 3 |
| Configuration | Single |
| Channel Mode | Depletion (normally-on at VGS = 0) |
| MSL 等级 | 1 (per JEDEC J-STD-020) |
| RoHS 状态 | Compliant |
| Lead-Free | Yes |
| 无卤 | Yes (Infineon 'green' package) |
BSS126H6327XTSA2 引脚配置
| 引脚 1 | Gate — Gate control input; negative VGS required to turn off depletion-mode channel |
| 引脚 2 | Source — Source terminal; reference node for gate drive |
| 引脚 3 | Drain — Drain terminal; high-voltage switching node |
典型应用
BSS126H6327XTSA2 适用于 6 应用s: Offline Flyback Startup Bias, Over-Voltage Protection Clamp, In-Rush Current Limiter, Offline Voltage Reference, Fail-Safe Relay Driver, Industrial Sensor Signal Conditioning.
Offline Flyback Startup Bias
The BSS126H6327XTSA2's 600 V VDS and depletion-mode (normally-on) characteristic make it ideal for offline flyback converter startup bias paths, where it must conduct before any controller is awake. Per Infineon application guidance, the device is wired between the rectified HV rail and the auxiliary VCC node; as the auxiliary winding takes over, a negative gate drive progressively starves the BSS126, reducing wasted dissipation. Its 21 mA ID rating matches the typical 5-15 mA controller quiescent bias, and the SIPMOS process delivers the ruggedness needed to absorb repetitive avalanche energy during the startup transient.
推荐
Over-Voltage Protection Clamp
For over-voltage protection clamps on auxiliary rails, the BSS126H6327XTSA2 provides a normally-on conduction path that latches into a defined fault state when a downstream Zener reference is exceeded. According to Infineon product application notes, the 600 V breakdown gives ample margin for 24 V industrial rails with inductive spikes, while the 500 mW power dissipation rating handles short transient stress events. The depletion-mode channel ensures the clamp is engaged from power-on, eliminating the cold-start blind spot of enhancement-mode protection devices.
推荐
In-Rush Current Limiter
In in-rush current limiters, the BSS126H6327XTSA2 acts as a series-pass element that begins conducting at power-on (depletion-mode normally-on) and is gradually pinched off by a control circuit as the downstream bulk capacitors charge. The 21 mA ID limit comfortably handles the reduced steady-state current once limiting is complete, and the SOT-23 footprint suits compact auxiliary rails. Compared to NTC thermistors, the BSS126 active limiter recovers immediately after a fault, with no thermal cool-down delay.
推荐
Offline Voltage Reference
As an offline voltage reference element, the BSS126H6327XTSA2 establishes a defined constant current into a Zener diode, producing a stable reference voltage on the high-voltage side before any isolation or regulation is active. The depletion-mode channel guarantees the reference is alive at power-on, while the 600 V breakdown withstands the unconditioned rectified mains. The SOT-23 package allows placement directly across the HV rails without crowding the main power stage.
推荐
Fail-Safe Relay Driver
For fail-safe relay driver paths, the BSS126H6327XTSA2's normally-on characteristic ensures the relay defaults to its energized state when the system controller is unpowered, satisfying safety requirements for alarm or emergency circuits. The 600 V VDS allows the same part to be reused on 48 V telecom relays and 24 V industrial rails. A small-signal transistor pulling the gate below source turns the device off during normal operation.
推荐
Industrial Sensor Signal Conditioning
In industrial 4-20 mA sensor loops and high-side current sources, the BSS126H6327XTSA2 provides a stable high-impedance constant-current element when biased with a source resistor. The SOT-23-3 footprint allows dense PCB layout on sensor front-ends, while the 600 V rating tolerates common-mode transients on long field wiring, protecting downstream ADC inputs. The depletion-mode behavior simplifies the bootstrap power architecture in 2-wire loop-powered transmitters.
推荐
推荐产品汇总
工程参考数据： BSS126H6327XTSA2 ——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 | BSS126H6906XTSA1 | BSS119NH6327XTSA1 | BSS127H6327XTSA2 | BSS123NH6327XTSA1 | BSS127S-7 |
|---|---|---|---|---|---|---|
| Package | SOT-23-3 (PG-SOT23) | SOT-23-3 (PG-SOT23) - same | SOT-23-3 (PG-SOT23) - same | SOT-23-3 (PG-SOT23) - same | SOT-23-3 (PG-SOT23) - same | SOT-23-3 - same |
| Brand | Infineon | Infineon | Infineon | Infineon | Infineon | Diodes Incorporated |
| FET Type | N-Channel Depletion | N-Channel Depletion | N-Channel Depletion | N-Channel Enhancement | N-Channel Enhancement | N-Channel Enhancement |
| Automotive Grade (AEC-Q101) | No | Yes (AEC-Q101) | No | No | No | No |
| RoHS / Halogen-Free | Yes / Yes | Yes / Yes | Yes / Yes | Yes / Yes | Yes / Yes | Yes / Yes |
关键差异点
- 600 V VDS in SOT-23-3 small-signal outline （对比 BSS127S-7 (Diodes Incorporated))
- Depletion-mode normally-on behavior （对比 BSS123NH6327XTSA1)
- Automotive-qualified variant available in same die （对比 BSS126H6906XTSA1)
设计说明
Do not leave the BSS126H6327XTSA2 gate floating. Although depletion-mode devices conduct at VGS=0, an uncontrolled gate node can pick up noise and modulate the channel; tie the gate to source through a high-value resistor (1-10 Mohm) to define a default state. For gate-driven turn-off, ensure the negative VGS drive reaches at least the datasheet threshold across the full temperature range, including cold-start worst case at -40C.
Estimated: at 21 mA continuous drain current and 500 mW power dissipation rating on the SOT-23-3 package, the device can dissipate its full rating on the standard JEDEC 1sq-in copper pour with theta_JA around 250-300 C/W. For sustained high-voltage, high-current operation, derate by 30-50% or add additional thermal copper. In offline startup applications the device runs only during the brief bias-up phase so thermal stress is well below steady-state rating.
Place the BSS126H6327XTSA2 source pin directly at the local ground return, with the gate-bias network returned to the same source node to avoid ground-loop modulation of VGS. Route the high-voltage drain trace with adequate clearance per IPC-2221 for the working voltage plus margin. Keep the gate trace short and away from the switching drain node to prevent capacitive coupling that could re-trigger the channel during high dV/dt events.
合规信息
RoHS and halogen-free green packaging per Infineon product compliance. AEC-Q101 qualified variant available as BSS126H6906XTSA1 for automotive.
