IRLML2803TRPBF - 30V/1.2A N-Channel HEXFET MOSFET from Infineon

What Is IRLML2803TRPBF and How Does It Work?

It is an enhancement-mode N-Channel MOSFET. Apply voltage between gate and source above the threshold (1V max), and the channel conducts between drain and source. The lower the R_DS(on), the less power you lose as heat. At 250mΩ and 1A, that is about 250mW - manageable for SOT-23 if your PCB has decent copper area.

Infineon's 5th-gen HEXFET process gives it fast switching (3.9ns turn-on, 9ns turn-off) and low gate charge (5nC). You do not need a dedicated gate driver for low-speed switching. A GPIO pin with a 10Ω–100Ω series resistor is enough to get clean switching without ringing.

Position in the product line: This is an entry-level logic-level MOSFET. Not the highest current, not the lowest R_DS(on) - but it is cheap, readily available, and works for the vast majority of light-load switching tasks in consumer electronics.

What Are the Specifications of IRLML2803TRPBF?

Why R_DS(on) matters here: 250mΩ at 10V is fine for loads up to ~800mA continuous. If you need to drive 2A+ through SOT-23, you are better off with a lower-R_DS(on) part like IRLML6344TRPBF (22mΩ) - but for small signal switching, this is plenty.

Watch the thermal budget. 540mW max at 25°C ambient, and that drops fast as temperature rises. With 1A through 250mΩ, you are at 250mW - about 46% of the budget. Comfortable if your PCB has decent copper pour, but tight in a dense layout.

Pinout (SOT-23)

   (TOP VIEW)

       D
       |
   G-| |-S

   Pin 1: Gate (G)
   Pin 2: Source (S)
   Pin 3: Drain (D)

Pin 1 is the gate (top-left when the tab faces away). Simple layout - no special routing needed beyond keeping gate traces short to avoid parasitic oscillation.

What Is IRLML2803TRPBF Used For?

Load Switches for Sensors and Peripherals

You need to cut power to a sensor in sleep mode to save battery. An IRLML2803TRPBF on the high side (with appropriate gate drive) or low side does the job. Draws near-zero leakage current (1µA typ) when off.

Why this part: Low gate charge means fast switching. Low leakage means no wasted battery in sleep.

Signal Level Shifting

Need to translate a 5V signal to 3.3V, or vice versa? A single N-FET with a pull-up resistor makes a classic bidirectional level shifter. The IRLML2803TRPBF's low threshold (1V max) works with both 3.3V and 1.8V logic.

Why this part: Low V_gs(th) and tiny package - you can fit 4 level shifters in the space of one DIP-8.

LED Drive

Switching low-power LEDs (up to ~500mA total) in portable devices. PWM dimming works fine - the fast switching edges give clean PWM without visible flicker.

DC-DC Converter Secondary Side

Not for the main switching element (you want a dedicated switching MOSFET for that), but useful for load disconnect, soft-start, or OR-ing diodes on lower-power rails.

Battery Protection

Low-side disconnect in single-cell Li-Ion protection circuits. The 30V rating covers 1S (4.2V) with huge margin, though for battery protection you would normally use a dedicated protection IC + dual N-FET.

IRLML2803TRPBF Cross-Reference and Alternatives

Pin-Compatible Direct Replacements (SOT-23)

Quick selection guide:

• Cheapest for your BOM: Stick with IRLML2803TRPBF - it is hard to beat at volume pricing.
• Need more headroom: VB1330 gives you 30mΩ vs 250mΩ in the same footprint. No PCB change needed.
• Obsolete replacement: If your legacy design used DMN100-7-F, IRLML2803TRPBF is the direct active replacement.
• Non-RoHS legacy: IRLML2803TR is the same die with lead - only use if your product has a RoHS exemption.

NOT Drop-in Compatible

How to Verify Genuine IRLML2803TRPBF?

The SOT-23 package is small, but counterfeits are out there. Here is what to check:

Visual inspection:

• Laser marking should be crisp. The standard marking is "L2" or "2803" depending on date/lot code.
• Pin 1 indicator (dot or notch) must be present.
• SOT-23 package height ~1.1mm. Any significant deviation is suspicious.

Electrical quick checks:

• Gate threshold: Measure V_gs(th) with a 250µA current source between drain and gate. Should be between 0.4V and 1.0V. If you measure 2V+, you have a standard-threshold part, not a logic-level.
• Diode check: Body diode between drain and source should read ~0.6V–0.7V. Short = dead part.
• R_DS(on) spot check: Apply 4.5V to gate, 100mA through drain-source, measure voltage drop. Calculate R = V/I. Should be below 350mΩ.

Batch traceability: At ICMASS, we source directly from Infineon authorized channels. Each reel comes with full traceability documentation. If you receive parts with missing or blurry date codes, that is a red flag.

Warranty: All IRLML2803TRPBF sold by ICMASS carry manufacturer warranty. If a part is suspect, we replace it - no questions.

Frequently Asked Questions About IRLML2803TRPBF

Q1: Can I drive IRLML2803TRPBF directly from a 3.3V microcontroller pin?

A: Yes. The gate threshold is 1V max, so 3.3V logic drives it fully into the ohmic region. At 3.3V gate drive, expect R_DS(on) around 300mΩ (typ) - about 20% higher than at 10V but still fine for most loads. Just add a 10Ω–100Ω series resistor to dampen ringing.

Q2: What is the difference between IRLML2803TRPBF and IRLML2803TR?

A: The suffix. "PBF" = lead-free (Pb-free) and RoHS compliant. "TR" = tape-and-reel packaging but may contain lead (non-RoHS). Electrically identical.

Q3: Can I use this as a replacement for DMN100-7-F?

A: Yes, it is pin-compatible and electrically very close (30V/1.2A vs 30V/1.1A, 250mΩ vs 240mΩ). In fact, IRLML2803TRPBF is the recommended active replacement since DMN100-7-F is obsolete.

Q4: Why is my IRLML2803TRPBF getting hot at only 500mA?

A: Check your gate drive voltage. If V_gs is below 3V, the MOSFET may be operating in the linear region instead of fully on. At V_gs = 2.5V, R_DS(on) can be 500mΩ+ - that means 125mW at 500mA, which in SOT-23 is enough to get warm. Solution: make sure your gate is driven to at least 3.3V, ideally 5V. Also check for oscillation on the gate - a 100Ω resistor in series usually fixes it.

Q5: What is the maximum PWM frequency for this MOSFET?

A: With 5nC gate charge and direct GPIO drive, you can comfortably switch at 100kHz. Push it to 500kHz+ if you use a gate driver. The switching times (3.9ns on, 9ns off) are fast enough for MHz-range, but the gate drive circuit becomes the bottleneck.

Q6: Is IRLML2803TRPBF suitable for automotive use?

A: Only if your application stays within the temperature range (-55°C to +150°C). But it is not AEC-Q101 qualified - for automotive, look at Infineon's automotive-grade MOSFETs (e.g., the AUIRL series).

Q7: Does IRLML2803TRPBF have ESD protection?

A: Infineon's HEXFETs typically have built-in ESD protection on the gate (2kV HBM). Still, standard ESD handling precautions apply - the gate oxide can be damaged by static discharge even with protection.

Q8: What is the leakage current when the MOSFET is off?

A: Typically 1µA at 25°C, rising to about 10µA at 85°C. Low enough for battery-powered devices, but not suitable for ultra-low-power applications where you need nA-level leakage - look at Infineon's OptiMOS series for that.

Q9: Can I parallel multiple IRLML2803TRPBF for higher current?

A: Technically yes, but not recommended. SOT-23 has poor thermal dissipation, and paralleling MOSFETs without ballasting can lead to current hogging and thermal runaway. You are better off using a single larger MOSFET.

Q10: What footprint / land pattern should I use for SOT-23?

A: Standard SOT-23 footprint - 2.9mm × 1.3mm body, 0.95mm pin pitch. The datasheet recommends a copper area of at least 50mm² on the PCB for thermal relief. More copper = better heat dissipation.

Q11: How do I tell counterfeit from genuine Infineon IRLML2803TRPBF?

A: Genuine parts have sharp, uniform laser marking, consistent date codes across the reel, and gate threshold within 0.4V–1.0V. Counterfeits often have blurry markings, mismatched date/lot codes, or V_gs(th) outside spec. Buy from ICMASS - we source from Infineon direct channels.

Pricing & Availability

Stock: Available for immediate shipment from Shenzhen warehouse.

Lead time: 3-5 business days for small quantities. Reel orders ship within 1-2 weeks depending on Infineon allocation.

Minimum order: No minimum for stocked parts. Sample quantities (1-10 pcs) available for evaluation.