BSS169H6327XTSA1 - 100V N-Ch Depletion MOSFET 170mA | Infineon
MPN: BSS169H6327XTSA1 ✓ Hoạt độngBSS169H6327XTSA1 Tóm tắt
A depletion-mode MOSFET (also called a depletion-mode or normally-on FET) is a field-effect transistor that conducts at zero gate-source bias. Unlike standard enhancement-mode MOSFETs (such as the ubiquitous 2N7002 or BSS138), which require a positive VGS to turn on, depletion-mode devices are on by default and require a negative gate bias to switch off. This normally-on behavior places depletion-mode MOSFETs in the broader family of field-effect transistors within power semiconductors, sitting alongside JFETs, standard MOSFETs, and IGBTs in the device taxonomy. The hypernym chain runs depletion-mode MOSFET -> field-effect transistor -> transistor -> discrete semiconductor.
Key features of the BSS169 include the always-on characteristic that simplifies startup circuitry, a pinch-off voltage around -3.5 V that allows digital logic drive from a single supply, low leakage at full pinch-off, and a small SOT-23 footprint that fits in any 0402-class board space. The device's 100 V drain rating provides generous headroom for 24 V industrial rails and telecom supply protection circuits. Its depletion-mode nature makes it particularly valuable in power-supply startup, in-rush-current limiting, over-voltage protection, and off-line voltage reference circuits where a normally-on pass element is preferred.
Technically, the BSS169 uses a vertical DMOS structure that gives it a low RDS(on) when fully on and a sharp pinch-off curve for clean switching. Designers exploit the always-on channel to pre-bias downstream stages or build constant-current sources using the saturation characteristic. Compared to enhancement-mode alternatives, the BSS169 simplifies gate-drive networks but requires careful handling because it cannot be turned off by simply pulling the gate to ground.
Typical applications include power-supply startup assistance (where it acts as a soft-start bypass), in-rush current limiters at the input of hot-plug DC rails, over-voltage protection crowbars, off-line voltage references for SMPS controllers, normally-on level shifters, and constant-current source circuits. The wide VDS range also suits it to 48 V telecom and PoE protection.
When designing with the BSS169, plan the gate-bias network first because the device is on at VGS=0. A typical circuit uses a resistor divider or zener clamp to set a defined pinch-off state during normal operation. Confirm that downstream circuits tolerate the always-on condition during power-up, and ensure the gate-source zener clamp does not exceed the +/-20 V VGS absolute maximum.
This page synthesizes distributor pricing from DigiKey and Mouser, drop-in alternatives verified against the SOT-23 footprint, and practical depletion-mode design notes that go beyond the manufacturer's datasheet.
Bộ thay thế dễ dàng lắp đặt cho BSS169H6327XTSA1 — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với BSS169H6327XTSA1 (cùng hình factor và footprint) — khác nhau ở Package, Technology, Continuous Drain Current (ID), Power Dissipation (PD), Drain-Source Voltage (VDS).
BSS139H6327XTSA1
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
BSS169H6327XTSA2
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
BSS169 L6327
✅ Drop-In ⚠️ Thông số chưa được xác minh📋 Tham chiếu thay thế (không có trong danh mục)
BSS83 H6327
✅ Drop-In ⚠️ Thông số chưa được xác minh📋 Tham chiếu thay thế (không có trong danh mục)
BSS84 H6327
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
2N7002L
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →BSS169H6327XTSA1 Tỷ lệ tối đa & tính chất điện
| FET Type | N-Channel Depletion Mode |
| Drain-to-Source Voltage (VDS) | 100 V |
| Continuous Drain Current (ID) | 170 mA (Ta) |
| Power Dissipation (PD) | 360 mW (Ta) |
| RDS(on) Maximum | 6 Ohm at VGS=0 V |
| Gate Threshold Voltage (VGS(th)) | Pinch-off approx. -3.5 V (typical) |
| Hộp | PG-SOT23 (SOT-23-3) |
| Kiểu lắp đặt | Surface Mount |
| Số chân | 3 |
| Cấp MSL | 1 (per JEDEC J-STD-020) |
| Trạng thái RoHS | Compliant |
| Lead-Free | Yes |
| Technology | Depletion-mode vertical DMOS |
| Drain Current at 25C | 170 mA continuous |
Cấu hình chân BSS169H6327XTSA1
| Chân 1 | Gate — Gate input; bias below pinch-off (~-3.5 V) to turn off |
| Chân 2 | Source — Source terminal; typically tied to circuit reference |
| Chân 3 | Drain — Drain terminal; up to 100 V VDS rating |
Khu vực hoạt động an toàn (DC)
Ứng dụng tiêu biểu
BSS169H6327XTSA1 phù hợp cho 6 Áp dụngs: Power Supply Startup Bypass, In-Rush Current Limiter, Over-Voltage Protection Crowbar, Off-Line Voltage Reference, Constant-Current Source, Normally-On Level Shifter.
Power Supply Startup Bypass
The BSS169H6327XTSA1's depletion-mode characteristic makes it ideal as a startup bypass element in switching power supplies, where it conducts at VGS=0 to provide initial power to the SMPS controller before the auxiliary winding takes over. With 100 V VDS headroom and 170 mA continuous drain current, it comfortably handles the housekeeping current of small flyback or buck converters during the first switching cycles. The 6 Ohm RDS(on) at zero gate bias limits inrush, and once the controller is powered it can pull the gate below pinch-off to fully disable the BSS169 for normal operation.
Được đề xuất
In-Rush Current Limiter
The BSS169H6327XTSA1 serves as a self-biased in-rush current limiter at the input of hot-plug DC rails (24 V industrial, 48 V telecom). Its normally-on channel with 6 Ohm RDS(on) limits the initial charging current of bulk output capacitors when a card is plugged into a live backplane. As the rail stabilizes, the controller can bias the gate below pinch-off to fully open the channel for minimum loss. The 100 V VDS rating handles transient spikes common in 24 V industrial environments without avalanche breakdown.
Được đề xuất
Over-Voltage Protection Crowbar
In over-voltage protection circuits, the BSS169H6327XTSA1 acts as a normally-on pass element that conducts during normal operation and is biased off by a sense circuit when an over-voltage event is detected. When paired with a comparator that drives the gate to pinch-off at a defined threshold, the BSS169 disconnects the load within microseconds, protecting downstream components from sustained over-voltage stress. Its 100 V VDS rating makes it suitable for crowbar protection on 24 V and 48 V rails.
Được đề xuất
Off-Line Voltage Reference
The depletion-mode BSS169H6327XTSA1 is well-suited to off-line voltage-reference circuits where a small constant current must flow from a high-voltage rail to a precision shunt reference such as a TL431. The always-on channel with predictable RDS(on) provides a defined current path without requiring a powered controller to bias the gate. This simplifies offline auxiliary supplies and self-powered gate-drive bias networks in SMPS designs.
Được đề xuất
Constant-Current Source
The BSS169H6327XTSA1's depletion-mode characteristic and stable pinch-off curve enable simple two-terminal constant-current source circuits. By tying gate to source through a resistor and operating the device in saturation, a fixed drain current can be set over a wide range of drain voltages. This is useful for LED biasing, loop-powered transducer excitation, and biasing of precision analog stages where a stable current reference is required from a varying supply.
Được đề xuất
Normally-On Level Shifter
In industrial and telecom interfaces, the BSS169H6327XTSA1 functions as a normally-on level shifter between a high-voltage domain (24 V or 48 V) and a low-voltage logic or microcontroller domain. Because the device conducts at VGS=0, a simple resistor divider on the gate is enough to define the OFF state for the low-voltage side, eliminating the need for an additional gate-drive supply. The 100 V VDS rating tolerates transients on the high-voltage rail without failure.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho BSS169H6327XTSA1 — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | BSS139H6327XTSA1 | BSS169H6327XTSA2 | BSS169 L6327 | BSS83 H6327 | 2N7002 |
|---|---|---|---|---|---|---|
| Brand | Infineon Technologies | Infineon Technologies | Infineon Technologies | Infineon Technologies | Infineon Technologies | onsemi |
| Package | PG-SOT23 (SOT-23-3) | PG-SOT23 (SOT-23-3) - same | PG-SOT23 (SOT-23-3) - same | PG-SOT23 (SOT-23-3) - same | PG-SOT23 (SOT-23-3) - same | SOT-23-3 - same |
| FET Type | N-Channel Depletion Mode | N-Channel Depletion Mode | N-Channel Depletion Mode | N-Channel Depletion Mode | N-Channel Depletion Mode | N-Channel Enhancement Mode |
| VDS Max | 100 V | 60 V | 100 V | 100 V | 60 V | 60 V |
| Continuous Drain Current (Ta) | 170 mA | 240 mA | 170 mA | 170 mA | 100 mA | 115 mA |
| RDS(on) Max | 6 Ohm | 10 Ohm | 6 Ohm | 6 Ohm | 10 Ohm | 7.5 Ohm at VGS=10V |
| Power Dissipation | 360 mW | 360 mW | 360 mW | 360 mW | 360 mW | 200 mW |
| VGS(th) / Pinch-Off | -3.5 V (typical pinch-off) | -3.5 V (typical pinch-off) | -3.5 V (typical pinch-off) | -3.5 V (typical pinch-off) | -3.5 V (typical pinch-off) | +1 to +2.5 V (enhancement threshold) |
| Pinout (G/S/D) | 1-G, 2-S, 3-D | 1-G, 2-S, 3-D | 1-G, 2-S, 3-D | 1-G, 2-S, 3-D | 1-G, 2-S, 3-D | 1-G, 2-S, 3-D |
Bảo phân biệt quan trọng
- One of the few depletion-mode small-signal MOSFETs in volume production (vs2N7002)
- Higher 100 V VDS rating than the BSS139 family (vsBSS139H6327XTSA1)
- Pin-compatible with standard SOT-23 small-signal MOSFETs (vsBSS83 H6327)
Ghi chú thiết kế
Because the BSS169H6327XTSA1 is depletion-mode and ON at VGS=0, it cannot be turned off by leaving the gate floating. Always provide a defined gate bias path - either a resistor to a known voltage or a zener clamp - to guarantee the desired OFF state during power-up and fault conditions. A floating gate can pick up noise and create undefined conduction states.
Estimated: at VDS=24 V, ID=170 mA continuous, RDS(on)=6 Ohm, the steady-state dissipation is approximately P = ID^2 * RDS(on) = 0.17^2 * 6 = 0.17 W, well within the 360 mW rating at 25C. However at 100 V VDS with the same current, designers must use pulsed operation or significantly derate for ambient temperature. The SOT-23 package has limited thermal headroom - check the SOA graph before operating at peak VDS and ID simultaneously.
Use a small copper pour under and around the drain pad to spread heat. Keep gate traces short and away from drain/source switching nodes to minimize parasitic coupling. For depletion-mode designs where the gate is biased through a high-impedance divider, add a 100 nF ceramic bypass between gate and source to shunt high-frequency noise that could otherwise modulate the channel.
In level-shifter or startup-bypass applications, the gate-source capacitance (Ciss) of the BSS169H6327XTSA1 can couple drain transients back to the gate through the Miller effect. A gate-source resistor of 100 kOhm to 1 MOhm helps discharge Ciss and stabilizes the OFF state during fast drain edges. Verify gate-bias network bandwidth against the fastest expected drain transition.
Thông tin tuân thủ
RoHS and REACH compliance per Infineon product page. Not AEC-Q100 qualified; this part is intended for industrial and consumer applications, not automotive. Lead-free reflow-compatible per MSL1 rating.
