BSZ0909NSATMA1 - 34V 36A N-Channel OptiMOS 25V MOSFET | Infineon
MPN: BSZ0909NSATMA1 β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.85 | $0.85 |
| 10 | $0.77 | $7.70 |
| 100 | $0.62 | $62.00 |
| 500 | $0.51 | $255.00 |
| 1,000 | $0.42 | $420.00 |
BSZ0909NSATMA1 Overview
An N-Channel MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) is a voltage-controlled majority-carrier device that uses a positive gate-source voltage to create an n-type inversion channel between drain and source. Within the broader power-semiconductor taxonomy, the BSZ0909NSATMA1 sits as: N-Channel MOSFET -> enhancement-mode power MOSFET -> power transistor -> discrete semiconductor. OptiMOS is Infineon's low-voltage power-MOSFET platform tuned for synchronous rectification, hot-swap, OR-ing, and point-of-load switching.
Key differentiating parameters include an ultra-low 1.31 nF C-iss at 15V VDS for fast switching edges, a 2V gate-source threshold for clean logic-level drive from 3.3V / 5V microcontrollers, and the TSDSON-8 footprint that occupies roughly 3.3 x 3.3 mm with a thermally efficient exposed pad. The device is qualified across -55C to +150C junction temperature and ships as RoHS-compliant.
Typical applications for BSZ0909NSATMA1 include synchronous buck converters in servers, datacom and telecom Point-of-Load (POL) rails, DC motor drive stages, USB-PD and battery protection FETs, hot-swap controllers, and low-side load switches. In each case the 12 mOhm R-DS(on) minimises conduction loss while 17 nC Qg keeps gate-driver losses low at high switching frequencies.
The most important design consideration is thermal management. Because the TSDSON-8's copper pad is the only effective heatsink, a multi-layer PCB with flooded top-layer copper directly under the exposed pad is required to keep Tj below 150C under continuous load. Designers must also respect SOA boundaries during pulsed load transients such as inrush or hot-plug events.
This page combines verified distributor pricing, parametric cross-references, and application-specific design guidance curated specifically for power-electronics engineers evaluating OptiMOS-class parts for 25V-30V rails.
Drop-in alternatives for BSZ0909NSATMA1 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 BSZ0909NSATMA1 (same form factor and footprint) β differing in Drain-Source Voltage (VDS), Package, Technology.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
BSZ0901NSIATMA1
β Drop-In β οΈ εζ°εΎ ιͺθ―β In Stock
$0.34 / Unit
View Datasheet βBSZ0900NSATMA1
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
DMN3010LK3-13
β Drop-Inπ Reference alternative (not in catalog)
BSZ0909NSATMA1 Maximum Ratings & Electrical Characteristics
| Transistor Type | N-Channel MOSFET |
| Technology | OptiMOS 25V |
| Drain-Source Voltage (VDS) | 34 V |
| Continuous Drain Current (ID) at TA=25C | 9 A |
| Continuous Drain Current (ID) at TC=25C | 36 A |
| R-DS(on) Max at VGS=10V | 12 mOhm at ID=20A |
| Gate-Source Threshold Voltage (VGS(th)) | 2 V at ID=250 uA |
| Total Gate Charge (Qg) | 17 nC at VGS=10V |
| Input Capacitance (Ciss) | 1.31 nF at VDS=15V |
| Power Dissipation (PD) at TA=25C | 2.1 W |
| Power Dissipation (PD) at TC=25C | 25 W |
| Operating Junction Temperature | -55C to +150C |
| Mounting Type | Surface Mount |
| Package | PG-TSDSON-8 (8-PowerTDFN) 3.3x3.3 mm |
| RoHS Status | Compliant |
BSZ0909NSATMA1 Pin Configuration
| Pin 1 | Source β Source connection (pin 1 of PG-TSDSON-8) |
| Pin 2 | Source β Source connection |
| Pin 3 | Source β Source connection |
| Pin 4 | Gate β Gate drive input |
| Pin 5 | Drain β Drain connection (tied to exposed pad) |
| Pin 6 | Drain β Drain connection (tied to exposed pad) |
| Pin 7 | Drain β Drain connection (tied to exposed pad) |
| Pin 8 | Drain β Drain connection (tied to exposed pad) |
Safe Operating Area (DC)
Typical Applications
BSZ0909NSATMA1 is suitable for 7 applications: Server and Datacom Point-of-Load Converters, Telecom Brick and DC-DC Modules, USB-PD and Battery Protection FETs, Hot-Swap and OR-ing Controllers, Brushless DC Motor Drive (Low-Side Switch), Industrial 24V Load Switches and Solenoid Drivers, Automotive Auxiliary and Body Electronics.
Server and Datacom Point-of-Load Converters
The BSZ0909NSATMA1 fits 12V-input POL buck converters in server and datacom VRMs because of its 34V VDS margin over nominal 12V rails and 17 nC total gate charge that keeps switching loss manageable above 500 kHz. With 12 mOhm R-DS(on) at VGS=10V, conduction loss in the synchronous FET is roughly 0.108W at 3A load, helping achieve >94% efficiency targets. Designers typically pair two BSZ0909NS devices in a synchronous half-bridge driven by a PWM controller, placed directly under a 3x3-mm copper pad for thermal relief.
Recommended
Telecom Brick and DC-DC Modules
In isolated telecom brick DC-DC stages and intermediate bus converters operating from a 24V or 48V input, the BSZ0909NSATMA1 can be used as a low-side synchronous rectifier on the secondary side after the transformer. Its 2V gate threshold ensures clean turn-on from standard 5V gate-drive signals, while the 1.31 nF Ciss at 15V VDS minimises driver losses. The PG-TSDSON-8 package's small footprint enables compact quarter-brick and eighth-brick designs where board real estate is at a premium.
Recommended
USB-PD and Battery Protection FETs
The BSZ0909NSATMA1 is well-suited as a high-side load switch or back-to-back battery-protection FET in USB-PD chargers and portable battery packs. Its 12 mOhm R-DS(on) keeps voltage drop under 100 mV at 8A charging currents, while the low Qg of 17 nC supports fast fault-disconnect response. Designers place the part on the source side of the load with a TVS diode for VBUS transient protection, taking advantage of the exposed thermal pad to dissipate heat during continuous 9A operation.
Recommended
Hot-Swap and OR-ing Controllers
Hot-swap and OR-ing applications in -48V telecom plants and redundant server power supplies benefit from the BSZ0909NSATMA1's 34V VDS rating and 36A pulsed ID capability, which tolerate inrush and load-step transients common during board insertion. The 12 mOhm R-DS(on) keeps forward voltage drop low in OR-ing diodes-replacement circuits, while the body diode supports reverse-current blocking when paired with a controller. A typical circuit places a gate resistor and TVS across the gate-source for transient immunity.
Recommended
Brushless DC Motor Drive (Low-Side Switch)
As a low-side switching element in small BLDC motor drives for fans, pumps and small appliances, the BSZ0909NSATMA1's 36A pulsed current rating easily handles the repetitive inrush during commutation. The 2V gate threshold ensures direct drive from 3.3V or 5V microcontroller GPIO without a separate gate driver. Designers combine three BSZ0909NS devices in a three-phase inverter topology, sized for continuous currents up to 9A per phase with the exposed thermal pad soldered to a copper pour for heat removal.
Recommended
Industrial 24V Load Switches and Solenoid Drivers
Industrial 24V load-switch and solenoid-driver designs benefit from the BSZ0909NSATMA1's 34V VDS providing comfortable transient margin over the 24V nominal rail, plus its 9A continuous ID supporting multi-solenoid multiplexed operation. The low R-DS(on) reduces thermal rise in long-duration PWM solenoid dimming applications, while the small PG-TSDSON-8 footprint allows dense PCB layouts. Pair with a free-wheel diode or use the body diode in flyback topologies, with the gate driven through a 100-ohm resistor for EMI control.
Recommended
Automotive Auxiliary and Body Electronics
Although the standard BSZ0909NSATMA1 is not AEC-Q100 qualified, its electrical characteristics match automotive-grade OptiMOS 25V pin-compatible parts in PG-TSDSON-8, making it useful for pre-production prototyping of body-electronics loads such as LED drivers, mirror controllers and small motor drives. The 12 mOhm R-DS(on) keeps conduction loss low in always-on circuits, while the wide -55C to +150C junction range covers under-hood and cabin environments. For production automotive designs use IAUCN-prefixed AEC-Q100 equivalents.
Recommended
Recommended Products Summary
Engineering reference data for BSZ0909NSATMA1 β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | BSZ0901NSIATMA1 | BSZ0900NSATMA1 | DMN3010LK3-13 |
|---|---|---|---|---|
| Brand | Infineon | Infineon | Infineon | Diodes Incorporated |
| Package | PG-TSDSON-8 (8-PowerTDFN) | PG-TSDSON-8 (8-PowerTDFN) - same | PG-TSDSON-8 (8-PowerTDFN) - same | PG-TSDSON-8 (8-PowerTDFN) - same |
| VDS Max | 34 V | 34 V | 34 V | 30 V |
| R-DS(on) Max at VGS=10V | 12 mOhm | 1 mOhm (approx, lower) | 9 mOhm (approx, lower) | 10 mOhm |
| Technology | OptiMOS 25V | OptiMOS 25V | OptiMOS 25V | DMOS |
Key Differentiators
- OptiMOS 25V technology provides best-in-class figure-of-merit (R-DS(on) * Qg) (vs DMN3010LK3-13 (Diodes Incorporated))
- Lower R-DS(on) at VGS=10V compared to higher-tier OptiMOS 25V parts (vs BSZ0900NSATMA1)
- Wider VDS margin over competitors (vs DMN3010LK3-13)
Design Notes
Estimated: at VDS=12V, ID=9A continuous in free air, the BSZ0909NSATMA1 dissipates P = I^2 * R = 81 * 0.012 = 0.97 W. The PG-TSDSON-8 has no thermal pad copper in the default JEDEC EIA/JESD51 footprint (theta_JA ~ 60 C/W), so Tj rises roughly 58C above ambient. To reach the 25W datasheet rating the PCB must include a copper pad of at least 6 cm^2 flooded on top layer and connected by 9 thermal vias to inner layers. Without this copper the device cannot sustain 9A continuous current at room temperature.
Place the BSZ0909NSATMA1 with its exposed thermal pad directly over a copper pour of at least 25 mm^2 per square inch of board area, with a 5x5 array of 0.3 mm thermal vias stitching to inner ground planes. Keep the high-current drain traces short and wide (50 mil minimum) to minimise parasitic inductance. The gate trace should be routed away from drain nodes and kept under 10 mm; add a 10 kohm pull-down on the gate to prevent floating-gate turn-on during hot-plug events.
In synchronous buck topologies, place the BSZ0909NSATMA1 synchronous FET adjacent to the bootstrap capacitor and PWM controller to minimise the gate-drive loop area. Use a 4-layer stackup with a solid ground plane beneath the FETs; route the SW (switch node) trace orthogonally to avoid coupling with the gate trace. A 1 nF ceramic snubber across the synchronous FET drain-source helps dampen ringing caused by parasitic inductance in the high-current loop.
Do not assume the BSZ0909NSATMA1 can survive avalanche events beyond its rated EAS. Avoid operating VDS near 30V for sustained periods because ringing on the switch node in buck converters can transiently exceed VDS and trigger avalanche, accelerating degradation. Always include a TVS diode (e.g. 33V SMAJ) across the drain-source in 24V-input designs, and ensure the gate-source voltage never exceeds +/-20V absolute maximum, even during transient turn-on events driven by high dv/dt on the drain node.
Estimated: the BSZ0909NSATMA1's 1.31 nF Ciss at 15V VDS combined with the gate-driver's output impedance forms an RC time constant that limits turn-on speed. With a typical 5-ohm driver, rise time tau = 5 * 1.31e-9 = 6.5 ns. To avoid excessive switching loss, keep the gate-drive supply voltage at 10V (not 5V) when switching 9A or more, since lower VGS increases R-DS(on) and conduction loss disproportionately. Add a 1-ohm gate resistor to dampen ringing if EMI is observed on the SW node.
Compliance Information
RoHS compliant per Infineon product page and DigiKey listing. Standard BSZ0909NSATMA1 is NOT AEC-Q100 qualified - for automotive applications use IAUCN-prefixed AEC-Q100 equivalents from the Infineon OptiMOS 25V automotive family.
