BSP135H6327XTSA1 - 600V N-Ch Depletion-Mode MOSFET | Infineon
MPN: BSP135H6327XTSA1 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.92 | $0.92 |
| 10 | $0.79 | $7.90 |
| 100 | $0.62 | $62.00 |
| 500 | $0.51 | $255.00 |
| 1,000 | $0.43 | $430.00 |
Drop-in alternatives for BSP135H6327XTSA1 — 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:
BSP135H6906XTSA1
✅ Drop-In✓ In Stock
$0.78 / Unit
View Datasheet →BSD214SNH6327XTSA1
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$0.27 / Unit
View Datasheet →BSL308CH6327XTSA1
✅ Drop-In✓ In Stock
$0.21 / Unit
View Datasheet →BSP315PH6327XTSA1
✅ Drop-In✓ In Stock
$0.31 / Unit
View Datasheet →BSP316PH6327XTSA1
✅ Drop-In✓ In Stock
$0.21 / Unit
View Datasheet →BSP135H6327XTSA1 Maximum Ratings & Electrical Characteristics
| Manufacturer | Infineon Technologies |
| Part Number | BSP135H6327XTSA1 |
| FET Type | N-Channel, Depletion Mode |
| Drain-Source Voltage (VDS) | 600 V |
| Continuous Drain Current (ID) | 120 mA |
| Power Dissipation (PD) | 1.8 W |
| On-Resistance RDS(on) max | 45 ohm at VGS = 0 V |
| On-Resistance RDS(on) | 25 ohm (typical, per digchip) |
| Operating Mode | Normally ON (depletion) |
| Package | PG-SOT223-4 (SOT-223-3 plus tab) |
| Mounting Type | Surface Mount |
| Technology | SIPMOS (planar DMOS) |
| Operating Temperature Range | -55C to +150C (junction, typical) |
| RoHS Status | Compliant |
| MSL Level | 1 |
BSP135H6327XTSA1 Pin Configuration
| Pin 1 | Gate — Gate control input; pinches off channel when VGS is sufficiently negative |
| Pin 2 | Drain — Drain terminal; connects to high-voltage load |
| Pin 3 | Source — Source terminal; reference for VGS and gate drive |
| Pin 4 | Drain (Tab) — Thermal tab internally connected to Drain; PCB copper heatsink required |
Safe Operating Area (SOA) & Thermal Characteristics
No official SOA curve available for this component. Always operate within absolute maximum ratings specified in the datasheet. Ensure adequate cooling and derate as needed.
Typical Applications
BSP135H6327XTSA1 is suitable for 6 applications: AC-DC Flyback High-Voltage Startup Circuit, Solar Inverter Active Discharge Circuit, Constant-Current Bias Source, High-Side Analog Switch / High-Voltage Mux, Overvoltage Protection Clamp, Industrial 24V/48V Bus Active Termination.
AC-DC Flyback High-Voltage Startup Circuit
The BSP135H6327XTSA1 is a textbook choice for the high-voltage startup path in isolated AC-DC flyback converters. Its depletion-mode normally-ON behavior allows the part to pass current from the 325 V rectified mains bus to the controller VCC rail at zero gate drive, before any auxiliary winding has produced voltage. Once the controller starts switching and VCC is sustained by the auxiliary winding, a Zener-resistor divider pulls the gate below source potential, pinching off the 45 ohm channel and disabling the lossy startup path. The 600 V VDS rating gives comfortable margin above the 325 VDC bus and absorbs leakage-inductance spikes. At 120 mA continuous current and 1.8 W dissipation, the part can supply typical controller start-up currents of 5-20 mA reliably for the few hundred milliseconds required.
Recommended
Solar Inverter Active Discharge Circuit
In solar inverter output stages, the BSP135H6327XTSA1 serves as an active discharge device that safely bleeds stored energy from DC-link capacitors when the inverter is shut down. Because the part is depletion-mode normally-ON, it will automatically conduct and discharge the link if the gate drive fails - a fail-safe behavior mandated by grid-tie safety standards. The 600 V VDS rating covers 600 VDC residential solar links with minimal derating margin, and the 45 ohm RDS(on) provides controlled discharge current without requiring a series discharge resistor. The SOT-223 package with tab heatsinking dissipates the discharge pulse energy within the 1.8 W package limit for typical 100-1000 uF link capacitance values.
Recommended
Constant-Current Bias Source
The depletion-mode characteristic of the BSP135H6327XTSA1 makes it well suited to simple two-terminal constant-current bias sources when paired with a source resistor. Operating in the saturation region with a fixed source resistor establishes a drain current approximately equal to |VGS(off)| / R_source, independent of drain voltage variations. This topology is used to bias depletion-mode amplifiers, sensor bridges, and reference zener diodes where the supply voltage can vary widely. The 600 V VDS rating allows the bias source to operate from high-voltage rails (up to 600 V) for instrumentation front-ends and tube-amp restoration projects. Source resistor values of 10-100 kohm yield bias currents in the 0.1-1 mA range.
Recommended
High-Side Analog Switch / High-Voltage Mux
When used as a high-side analog switch, the BSP135H6327XTSA1 can pass small signals up to 600 V peak with the channel fully enhanced at VGS = 0 and pinched off at sufficiently negative VGS. This makes it useful for high-voltage signal multiplexing in test-and-measurement equipment, defibrillator output stages, and electrostatic precipitator controls. The 45 ohm RDS(on) introduces modest on-state attenuation but is acceptable for high-impedance loads. The normally-ON behavior provides a fail-safe conduction path - if gate drive is lost, the switch defaults to ON rather than OFF, which is desirable in some safety circuits and undesirable in others (verify per application).
Recommended
Overvoltage Protection Clamp
The BSP135H6327XTSA1 can be wired as a source-follower overvoltage clamp: source connects to the protected rail, gate is held at the desired clamp threshold by a Zener diode, and drain connects to ground. When the rail voltage exceeds the Zener plus VGS(off), the channel pinches off and conducts current to ground, shunting overvoltage energy. The 600 V VDS rating makes the part suitable for protecting low-voltage circuits from high-voltage transients on industrial signal lines. The 120 mA continuous current capability handles transient surges up to the 1.8 W package dissipation limit when the tab is heatsinked. For sustained overvoltage events, an external fuse or PTC should limit the energy.
Recommended
Industrial 24V/48V Bus Active Termination
In industrial fieldbus systems (PROFIBUS, RS-485 isolated segments, CAN bus in 24V industrial environments), the BSP135H6327XTSA1 serves as an active bus terminator that conducts at zero gate drive and disconnects when the bus is intentionally de-energized. The 600 V VDS rating provides robust protection against common-mode transients from inductive motor loads on the same industrial backplane. Although normally used in 5V logic-level buses, the high VDS margin allows the BSP135H6327XTSA1 to survive the harsh electrical environment of factory automation systems, where smaller MOSFETs would avalanche and fail.
Recommended
Recommended Products Summary
Engineering reference data for BSP135H6327XTSA1 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | BSP135H6906XTSA1 | BSD214SNH6327XTSA1 | BSL308CH6327XTSA1 | BSP315PH6327XTSA1 | BSP316PH6327XTSA1 |
|---|---|---|---|---|---|---|
| Brand | Infineon Technologies | Infineon Technologies | Infineon Technologies | Infineon Technologies | Infineon Technologies | Infineon Technologies |
| Package | PG-SOT223-4 | PG-SOT223-4 - same | PG-SOT223-4 - same | PG-SOT223-4 - same | PG-SOT223-4 - same | PG-SOT223-4 - same |
| FET Type | N-Channel Depletion (normally ON) | N-Channel Depletion (normally ON) | N-Channel Enhancement | N-Channel Enhancement | P-Channel Enhancement | N-Channel Enhancement |
| Drain-Source Voltage (VDS) | 600 V | 600 V | 20 V | 30 V | 60 V | 100 V |
| Continuous Drain Current (ID) | 120 mA | 120 mA | 1.9 A | 2.1 A | 1.2 A | 3.6 A |
| On-Resistance RDS(on) max | 45 ohm | 45 ohm | 0.14 ohm | 0.05 ohm | 0.25 ohm | 0.08 ohm |
| Power Dissipation (PD) | 1.8 W | 1.8 W | 1.8 W | 2.0 W | 1.8 W | 1.8 W |
| Mounting Type | Surface Mount | Surface Mount | Surface Mount | Surface Mount | Surface Mount | Surface Mount |
| RoHS | Compliant | Compliant | Compliant | Compliant | Compliant | Compliant |
Key Differentiators
- Only depletion-mode 600 V part in SOT-223 in the Infineon lineup (vs BSP315PH6327XTSA1 (P-channel enhancement))
- Fail-safe conduction on gate drive loss (vs BSD214SNH6327XTSA1 (N-channel enhancement))
- 600 V VDS in SOT-223 footprint - rare combination (vs BSL308CH6327XTSA1 (30 V enhancement))
- Same footprint as enhancement-mode SOT-223 MOSFETs (vs Industry-standard SOT-223 enhancement-mode MOSFETs)
Design Notes
Depletion-mode MOSFETs conduct at VGS = 0 V. Unlike enhancement-mode MOSFETs which require VGS(th) to be exceeded to turn ON, the BSP135H6327XTSA1 MUST have its gate actively biased to turn OFF. An open or floating gate leaves the device fully ON. Always include a defined gate-source path - either a Zener-resistor divider to a known reference, or a gate-source pull-down resistor - in the schematic. Floating gates on depletion-mode parts are a common cause of field failures.
The 1.8 W power dissipation rating of the BSP135H6327XTSA1 requires the tab (pin 4) to be soldered to a minimum copper pour area of approximately 1 square inch (645 mm^2) on the PCB to achieve the datasheet thermal resistance. Without this heatsinking, the actual continuous dissipation must be derated below 1 W. For pulsed operation (such as active discharge of a DC-link capacitor), the instantaneous power can exceed 1.8 W if the pulse duration is short enough that the thermal mass of the package and copper prevents junction temperature rise above 150 C - calculate using the transient thermal impedance curve in the datasheet.
Route the gate trace away from the drain trace to minimize capacitive coupling. The drain-to-gate capacitance (Cgd, typically a few pF for this small device) can couple fast drain voltage transients back to the gate, causing unwanted turn-off or oscillation. A 10-100 kohm gate resistor in series with the gate, placed close to the IC, damps this coupling. Place a local 100 nF ceramic bypass from VCC to ground near any active-mode controller driving the BSP135H6327XTSA1 gate.
When using the BSP135H6327XTSA1 as a high-side analog switch, the 45 ohm on-resistance is significantly higher than typical enhancement-mode analog switches (which are often below 10 ohm). For high-impedance loads (greater than 10 kohm), this on-resistance introduces less than 0.5% attenuation and is acceptable. For low-impedance loads, the on-resistance becomes a significant portion of the load and must be accounted for in the design. The off-state leakage when pinched off is typically below 1 uA at room temperature and increases exponentially with temperature.
Estimated: At VDS = 325 V (rectified 230 VAC bus) and ID = 100 mA continuous, the BSP135H6327XTSA1 dissipates approximately 32.5 W - far exceeding the 1.8 W package limit. This calculation shows why depletion-mode 600 V MOSFETs are NEVER used as main power switches - they are strictly for low-current biasing and startup paths where ID remains below 120 mA and duty cycle is low. For continuous high-voltage current paths, choose a power MOSFET rated for the wattage (e.g. the IAUT300N10S5N015ATMA1 in the Site MPN list).
Compliance Information
RoHS and lead-free status confirmed by Infineon product page. Halogen-free status not explicitly stated in the verified data; AEC-Q100 not applicable for this industrial-grade part - automotive variants would carry a different ordering code.
