BSP149H6327XTSA1 - 200V N-Ch Depletion-Mode MOSFET | Infineon
MPN: BSP149H6327XTSA1 β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.17 | $1.17 |
| 10 | $1.02 | $10.20 |
| 100 | $0.85 | $85.00 |
| 500 | $0.72 | $360.00 |
| 1,000 | $0.6 | $600.00 |
BSP149H6327XTSA1 Overview
Key features include 200 V VDS rating, 660 mA ID continuous, 1.8 W power dissipation, low on-resistance of 1 ohm typical, and integrated gate protection. Because it is a depletion-mode device, it requires a negative gate bias to switch off; this makes it useful in constant-current sources, analog signal switches, and active loads where normally-off behavior cannot be assumed. Designers must apply a VGS of approximately -2.5 V or lower to fully turn the device off, while VGS = 0 V leaves the channel fully open with ID limited only by the load and the on-resistance.
Architecturally, the BSP149H6327XTSA1 uses a vertical SIPMOS (Siemens Power MOS) structure with the source, gate, and drain brought out to separate pins, with the tab functioning as the drain connection to maximize thermal conduction to the PCB. The PG-SOT223-4 footprint is one of the most widely used SOT-223 outlines and allows straightforward replacement with both SOT-223-3 and SOT-223-4 variants as long as the pinout matches.
Typical applications include constant-current sources, active loads, normally-on power switches, analog multiplexer and signal routing, automotive 12 V/24 V load management (where the depletion-mode behavior simplifies fail-safe circuit design), and solid-state relay front-ends. In audio circuits, depletion-mode devices are occasionally used in source-follower configurations for current sources where the gate can be biased to set ID.
A key design consideration is gate-source bias: the gate cannot be left floating, or the device will remain ON. A pull-down or active bias network is required to guarantee a defined off-state. Designers should also respect the safe operating area (SOA) at higher VDS, especially during inductive load switching where avalanche energy must be considered.
This page consolidates distributor pricing, drop-in alternatives, and practical design notes that go beyond the datasheet, helping engineers select the right Infineon part for depletion-mode analog and switching applications.
Drop-in alternatives for BSP149H6327XTSA1 β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with BSP149H6327XTSA1 (same form factor and footprint) β differing in Package, Technology, RoHS Status, Drain-Source Voltage (VDS), FET Type.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
BSP149 E6327
β Drop-Inπ Reference alternative (not in catalog)
BSP149H6327XTSA2
β Drop-Inπ Reference alternative (not in catalog)
BSS806NH6327XTSA1
β Drop-Inβ In Stock
$0.19 / Unit
View Datasheet βBSS316NH6327XTSA1
β Drop-Inβ In Stock
$0.13 / Unit
View Datasheet βBSS214NH6327XTSA1
β Drop-Inβ In Stock
$0.09 / Unit
View Datasheet βBSP149H6327XTSA1 Maximum Ratings & Electrical Characteristics
| Transistor Polarity | N-Channel |
| Mode of Operation | Depletion Mode (normally ON) |
| Drain-Source Voltage VDS | 200 V |
| Continuous Drain Current ID | 660 mA (Ta) |
| Power Dissipation PD | 1.8 W (Ta) |
| On-State Resistance RDS(on) | 1 ohm (typ) |
| Package | PG-SOT223-4 (SOT-223-4) |
| Mounting Type | Surface Mount |
| Operating Temperature | -55 C to +150 C (Tj) |
| Technology | SIPMOS |
| Channel Count | 1 |
| Pin Count | 4 (G, D, S, tab) |
| RoHS Status | Compliant |
| Configuration | Single |
BSP149H6327XTSA1 Pin Configuration
| Pin 1 | G β Gate - controls channel conduction (depletion mode) |
| Pin 2 | D β Drain - power input/output terminal |
| Pin 3 | S β Source - power input/output terminal |
| Pin 4 | D (Tab) β Drain tab - thermal pad, internally connected to pin 2 (Drain) |
Safe Operating Area (DC)
Typical Applications
BSP149H6327XTSA1 is suitable for 6 applications: Constant-Current Source, Active Load / Electronic Load, Analog Signal Switch / Multiplexer, Normally-On Power Switch / Fail-Safe Circuit, Solid-State Relay Front-End, Automotive 12 V/24 V Load Driver.
Constant-Current Source
The BSP149H6327XTSA1's depletion-mode normally-on behavior and 200 V VDS make it well-suited for high-side and low-side constant-current sources in industrial analog signal conditioning and instrumentation. With VGS biased to a fixed negative voltage via a Zener or resistor divider, the device sets ID by RDS(on) and the load resistor; at 660 mA continuous rating and 1.8 W PD, designers have ample headroom for 10-100 mA precision current sources in 24 V process-control loops.
Recommended
Active Load / Electronic Load
The BSP149H6327XTSA1 can serve as the pass element in an electronic load for power-supply testing and battery discharge characterization up to 200 V and 660 mA. Its 1.8 W dissipation in SOT-223-4 supports moderate-power bench testing when mounted on adequate copper. The depletion-mode behavior means the circuit begins conducting at power-up; an active gate-bias driver is required to implement CC/CV control.
Recommended
Analog Signal Switch / Multiplexer
The BSP149H6327XTSA1 functions as an analog switch in test equipment, audio routing, and instrumentation multiplexing where its 200 V rating supports high-voltage signal paths. With the gate biased OFF via a negative voltage, the device blocks signal; with VGS = 0, it passes the signal. The 1 ohm RDS(on) is acceptable for high-impedance signal paths but introduces measurable insertion loss in low-impedance circuits.
Recommended
Normally-On Power Switch / Fail-Safe Circuit
The BSP149H6327XTSA1 is ideal for fail-safe power switches in 24 V and 48 V industrial rails where a depletion-mode device remains ON if the gate-bias supply fails. This protects downstream loads in safety-critical applications. The 200 V VDS rating provides 4x margin over typical 48 V rails, and the 660 mA continuous current handles relay coils, fans, and small solenoids.
Recommended
Solid-State Relay Front-End
In solid-state relay designs the BSP149H6327XTSA1 can drive the output stage or serve as the input-side switch. Its 200 V blocking voltage and normally-on characteristic simplify AC-line switching circuits where fail-safe behavior is desired. Combined with an optocoupler driver, designers can build SSR modules rated for industrial 230 VAC control.
Recommended
Automotive 12 V/24 V Load Driver
Although not AEC-Q100 qualified, the BSP149H6327XTSA1 is widely used in non-safety automotive subsystems for 12 V and 24 V load management where its 200 V VDS gives substantial transient margin. The SOT-223-4 package is rugged for under-hood environments, and the depletion-mode behavior simplifies eFuse and load-dump protection circuits. Designers should verify temperature range and add TVS protection for ISO 7637-2 compliance.
Recommended
Recommended Products Summary
Engineering reference data for BSP149H6327XTSA1 β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | BSP149 E6327 | BSP149H6327XTSA2 | BSS806NH6327XTSA1 | BSS316NH6327XTSA1 | BSS214NH6327XTSA1 |
|---|---|---|---|---|---|---|
| Brand | Infineon | Infineon | Infineon | Infineon | Infineon | Infineon |
| Package | PG-SOT223-4 | PG-SOT223-4 - same | PG-SOT223-4 - same | SOT-23 | SOT-23 | SOT-23 |
| Mode | Depletion (normally ON) | Depletion | Depletion | Depletion | Depletion | Depletion |
| VDS (V) | 200 | 200 | 200 | 20 | 30 | 20 |
| ID continuous (mA) | 660 | 660 | 660 | 2300 | 1100 | 2500 |
| PD (W) | 1.8 | 1.8 | 1.8 | 0.5 | 0.5 | 0.5 |
| RDS(on) (ohm) | 1 | 1 | 1 | 0.05 | 0.1 | 0.045 |
| Source | web_data | web_data | web_data | web_data | web_data | web_data |
Key Differentiators
- 200 V VDS rating - substantially above typical small-signal MOSFETs (vs BSS806NH6327XTSA1)
- SOT-223-4 thermal performance vs SOT-23 alternatives (vs BSS316NH6327XTSA1)
- Depletion-mode normally-ON behavior is rare in production MOSFETs (vs Standard enhancement-mode MOSFETs)
Design Notes
Because the BSP149H6327XTSA1 is a depletion-mode device, the gate cannot be left floating. A floating gate allows leakage currents to charge VGS unpredictably, leaving the device in an undefined conduction state. Always provide an active pull-down or negative bias network to guarantee OFF-state. Common circuits use a Zener diode in series with a pull-down resistor to generate a fixed negative gate bias.
Estimated: at ID = 660 mA and RDS(on) = 1 ohm, internal dissipation is ID^2 x RDS(on) = 0.43 W. The SOT-223-4 package's theta_JA is typically 80 C/W on a 1 oz copper pour, yielding a junction-temperature rise of approximately 35 C above ambient - well within the 150 C rating. For sustained operation near PDmax, allocate at least 1 square inch of drain-tab copper to maintain thermal margin.
The SOT-223-4 drain tab (pin 4) must be soldered to a copper pour sized for the application's thermal and current requirements. Minimal pad geometry increases both thermal resistance and parasitic inductance, which can cause ringing during fast switching transitions. Use multiple thermal vias under the tab to the opposite PCB plane to spread heat; this also reduces mechanical stress on the solder joints during thermal cycling.
When using the BSP149H6327XTSA1 as an analog switch, source-follower or constant-current source, account for the gate-source capacitance (Ciss, Coss) in your bandwidth calculation. The relatively large die in a SOT-223-4 package introduces Ciss in the tens of picofarads range, which limits switching speed and creates a pole that must be compensated if the gate is driven from a high-impedance source.
Compliance Information
RoHS and lead-free per Infineon product page. Not AEC-Q100 qualified - not intended for automotive safety-critical applications. Halogen-free per Infineon SIPMOS family standard.
