My Inquiry
My Account
Infineon Technologies IR3871MTR1PBF
- Part No.:
- IR3871MTR1PBF
- Manufacturer:
- Infineon Technologies
- Package:
- 17-PowerVQFN
- Datasheet:
-
IR3871MTR1PBF.pdf
- Description:
- IC REG BUCK ADJ 8A PQFN
- Quantity:
- Payment:
- Shipping:
Inventory:1,106
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
IR3871MTR1PBF from Infineon Technologies is a highly integrated synchronous buck regulator with integrated high- and low-side MOSFETs, constant on-time control, and 8A continuous output current capability. It operates from 3V to 26V input, delivers 0.5V–12V output with ±1% reference accuracy, and features programmable switching frequency, soft-start, over-current protection, and power-good signaling - deployed in notebook DC-DC point-of-load (POL) supplies.
For engineers reviewing the IR3871MTR1PBF datasheet, IR3871MTR1PBF pinout, IR3871MTR1PBF application, or IR3871MTR1PBF equivalent, key selection criteria include its 5×6mm QFN-17 package, integrated FETs eliminating external driver complexity, pre-bias startup support, and no-compensation-loop design enabling rapid layout and stable transient response in space-constrained POL systems.
Technical Context
The IR3871MTR1PBF implements a constant on-time (COT) hysteretic control architecture that enables fast load-transient response without external loop compensation. Its internal 0.5V ±1% voltage reference feeds the FB comparator, while the ISET pin sets over-current trip via resistor-to-PHASE connection.
It integrates dual MOSFETs (14.5–25.5 mΩ high-side, 8–12.5 mΩ low-side), a bootstrap gate drive (BOOT–PHASE), feed-forward input (FF) for on-time adjustment, and dedicated PGND/GND separation for noise immunity. The device supports pre-bias startup, under/over-voltage fault shutdown, and EN-based input voltage monitoring with hysteresis.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 3V to 26V - supports wide-input industrial and computing rails including 5V, 12V, 19V adapters. |
| Output Voltage Range | 0.5V to 12V - adjustable via FB resistor divider; precision 0.5V reference enables sub-1V core supply generation. |
| Continuous Output Current | 8A - sustained at 60°C ambient without airflow, enabled by low RDS(on) MOSFETs and thermal QFN package. |
| Switching Frequency | Programmable up to 1000 kHz - set via FF resistor; higher frequencies reduce output filter size but increase switching loss. |
| Reference Accuracy | ±1% (0.495V–0.505V) - ensures tight output regulation across line/load/temperature for CPU/GPU core rails. |
| Protection Features | OCP (via ISET), UVP/OVP (FB-sensed), PGOOD open-drain, thermal shutdown - enables autonomous fault handling in unattended systems. |
| Package | 5mm × 6mm QFN-17 - exposed thermal pad improves θJA = 35°C/W; compatible with standard reflow profiles (MSL2 @ 260°C). |
Pinout & Package
IR3871MTR1PBF uses a thermally enhanced 5mm × 6mm QFN-17 package with exposed thermal pad (PGND-connected). Pin 1 is NC (no connection); pins 4 and 17 are GND; pin 11 is PGND (power ground return); pin 12 is PHASE (switch node); pin 13 is VIN (main input); pin 14 is BOOT (bootstrap capacitor connection to PHASE); pin 16 is EN (enable with voltage-monitoring capability).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| FB (Pin 5) | Inverting input to PWM comparator | Senses output voltage via resistor divider; triggers OVP/UVP shutdown and PGOOD assertion at 0.58V/0.40V thresholds. |
| SS (Pin 6) | Soft-start/shutdown control | Capacitor-to-GND sets ramp time; pulled below 0.3V to force shutdown - enables sequencing and fault recovery. |
| VCC (Pin 10) | Gate drive supply | Internal LDO output (3.3V) powers high-side driver; requires ≥1µF ceramic decoupling to PGND. |
| PGOOD (Pin 3) | Open-drain status output | Asserts high when VOUT is within ±7% of target; used for system power sequencing and fault indication. |
| ISET (Pin 2) | Over-current threshold setting | Resistor from ISET to PHASE sets current limit; 20 µA sink enables precise trip point calibration. |
| EN (Pin 16) | Enable with input monitoring | Turn-on threshold 4.2V (typ), hysteresis 150 mV - allows direct connection to regulated 5V rail or resistive divider from VIN. |
Key Features
| Feature | Design Value |
|---|---|
| No external compensation required | Constant on-time control eliminates feedback loop components - reduces BOM count and layout sensitivity to parasitics. |
| Pre-bias startup capability | Allows safe turn-on into pre-charged output capacitors - prevents reverse current flow and avoids system reset during hot-swap events. |
| Integrated dual MOSFETs | High-side RDS(on) = 20.8 mΩ (typ), low-side = 10 mΩ (typ) - eliminates discrete driver + FET selection, simplifies thermal design. |
| Power Good with delay threshold | PGOOD asserts only after VOUT stabilizes above 0.93×VREF for ≥1 ms - prevents false assertions during soft-start overshoot. |
| Feed-forward on-time programming | RFF from FF (Pin 15) to VIN sets nominal on-time - maintains consistent regulation across wide input ranges without loop tuning. |
Applications
| Notebook Core Voltage Regulation | Gaming Console SoC Power |
|---|---|
|
Use Scenario: Regulating CPU/GPU core voltage (e.g., 0.85V @ 6A) in ultrabook platforms with strict thermal envelope and no forced airflow. IC Role / Device Role / Timing Role: Primary synchronous buck POL regulator delivering dynamically scaled core voltage with fast transient response. Use Value: Constant on-time control and integrated FETs enable <100 ns load-step response and >90% efficiency at 1A–8A, reducing heatsink requirements. |
Use Scenario: Supplying 1.1V/7A to AMD/Intel SoCs in compact gaming consoles where board area and EMI are critical constraints. IC Role / Device Role / Timing Role: High-density, single-chip buck converter replacing multi-component solutions for main SoC rail. Use Value: 5×6mm QFN footprint and no-compensation design cut PCB area by >40% vs. controller+driver+FET alternatives. |
| STB & Smart TV DDR Memory Rail | Industrial Embedded FPGA I/O Bank Supply |
|
Use Scenario: Generating 1.2V/5A for DDR4 memory subsystems in set-top boxes requiring low-noise, high-reliability operation over -20°C to 70°C. IC Role / Device Role / Timing Role: Precision-adjustable POL regulator with ±1% reference and OVP/UVP protection for memory interface stability. Use Value: Tight 0.5V reference tolerance and 10 mV UV/OV hysteresis prevent memory timing violations during brown-out conditions. |
Use Scenario: Providing 1.8V/4A to FPGA I/O banks in factory automation controllers where long-term supply continuity and thermal robustness are mandatory. IC Role / Device Role / Timing Role: Industrial-grade buck regulator with MSL2 moisture sensitivity and 150°C max junction temperature rating. Use Value: Junction temperature range (-40°C to 150°C) and PGND/GND separation ensure reliable operation in sealed enclosures with limited convection cooling. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar synchronous buck regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MP2451DT-LF-Z (Monolithic Power) | 3A rated, external MOSFETs required, requires compensation network, 2–24V input | Limited to lower-current applications; lacks integrated FETs and pre-bias startup | Choose when cost sensitivity outweighs integration needs and current demand ≤3A. |
| TPS54821RHLR (Texas Instruments) | 8A, integrated FETs, voltage-mode control with external compensation, 4.5–20V input | Requires loop compensation components; no feed-forward on-time adjustment; narrower input range | Prefer when design requires voltage-mode stability analysis or compatibility with TI's WEBENCH toolchain. |
Compared with MP2451DT-LF-Z and TPS54821RHLR, the IR3871MTR1PBF delivers higher integration (no external drivers or compensation), wider input range (3–26V), and unique COT-based transient performance - making it optimal for compact, high-efficiency POL designs where layout simplicity and fast load response are prioritized.
Availability
IR3871MTR1PBF is available at Aetrix Electronics and suitable for notebook power delivery, gaming console SoC supplies, and STB DDR memory rails requiring stable component supply, long-lifecycle availability, and MSL2-compliant packaging.
Supply support for IR3871MTR1PBF includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Infineon Technologies is a German semiconductor manufacturer specializing in power management, automotive ICs, and industrial control solutions, with global manufacturing and quality certification to ISO/TS 16949 and IATF 16949.
The IR3871 belongs to Infineon's SupIRBuck™ family - engineered for high-efficiency, space-constrained point-of-load regulation in computing and consumer electronics, emphasizing integration, thermal performance, and ease of use.
FAQ
What is the maximum allowable input voltage for IR3871MTR1PBF?
The absolute maximum input voltage (VIN) is 30V, but the recommended operating range is 3V to 26V per datasheet specifications. Exceeding 26V may trigger overvoltage protection or degrade reliability; the PHASE pin must not exceed 30V DC or -5V for 100ns transients.
Does IR3871MTR1PBF require an external compensation network?
No - the IR3871MTR1PBF uses constant on-time (COT) hysteretic control, eliminating the need for external compensation components like type-II or type-III networks. This simplifies layout, reduces component count, and improves stability across varying output capacitance and ESR.
How is over-current protection configured on IR3871MTR1PBF?
OCP is set by connecting a resistor between ISET (Pin 2) and PHASE (Pin 12). The device sinks 20 µA (typ) from ISET; trip current equals (0.1V / RISET) × 1000, where RISET is the resistor value. For example, a 10 kΩ resistor sets ~10A trip, adjusted per application current margin.
Can IR3871MTR1PBF start up into a pre-biased output?
Yes - the IR3871MTR1PBF supports pre-bias startup. During turn-on, it monitors the FB pin and delays high-side FET activation until the output voltage falls below the programmed regulation level, preventing reverse current flow and ensuring controlled ramp-up into existing bus voltage.
IR3871MTR1PBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Infineon Technologies
- Series:
- SupIRBuck®
- Package/Case:
- 17-PowerVQFN
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Function:
- Step-Down
- Output Configuration:
- Positive
- Topology:
- Buck
- Output Type:
- Adjustable
- Number of Outputs:
- 1
- Voltage - Input (Min):
- 3V
- Voltage - Input (Max):
- 26V
- Voltage - Output (Min/Fixed):
- 0.5V
- Voltage - Output (Max):
- 12V
- Current - Output:
- 8A
- Frequency - Switching:
- Up to 1MHz
- Synchronous Rectifier:
- Yes
- Operating Temperature:
- 0°C ~ 125°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- PQFN (5x6)
IR3871MTR1PBF FAQ
1.How can I place an order for IR3871MTR1PBF through Aetrix?
Please submit a Request for Quotation (RFQ) for IR3871MTR1PBF on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for IR3871MTR1PBF reliable?
The price and inventory of IR3871MTR1PBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for IR3871MTR1PBF is usually 5 days.
3.What payment methods are accepted for IR3871MTR1PBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for IR3871MTR1PBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for IR3871MTR1PBF?
IR3871MTR1PBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your IR3871MTR1PBF order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for IR3871MTR1PBF?
For technical support, including IR3871MTR1PBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your IR3871MTR1PBF requirements.
6.How does Aetrix verify that IR3871MTR1PBF is sourced from the original manufacturer or authorized distributors?
All IR3871MTR1PBF products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that IR3871MTR1PBF meets industry standards.
7.What is the process for return or replacement of IR3871MTR1PBF?
All IR3871MTR1PBF units undergo pre-shipment inspection (PSI). If there is an issue with IR3871MTR1PBF, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The IR3871MTR1PBF part is unused and in its original packaging.
Return procedure for IR3871MTR1PBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
IR3871MTR1PBF Tags
-
TPS562201DDCR
Texas Instruments
-
MC34063ABD-TR
STMicroelectronics
-
TPS561201DDCR
Texas Instruments
-
MC33063ADR
Texas Instruments
-
MC34063ADR
Texas Instruments
-
TPS560200DBVR
Texas Instruments
-
AP3012KTR-G1
Diodes Incorporated
-
TLV61048DBVR
Texas Instruments
-
AZ34063UMTR-G1
Diodes Incorporated
-
TPS562200DDCR
Texas Instruments
-
AP62300TWU-7
Diodes Incorporated
-
MC34063EBD-TR
STMicroelectronics
Tech Hub
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
LDO regulator guide covering low dropout voltage, power dissipation, thermal design, PSRR, output noise, capacitor stability, adjustable LDO circuits, LDO vs buck converter and datasheet selection chec…
Conditional Access Module guide covering CAM meaning, CI/CI+ interface, smart card authorization, DVB security workflow, TV and set-top box compatibility, internal electronics, ESD protection, connecto…
Guide to electronic component obsolescence covering EOL risk, PCN/PDN notices, last-time buy planning, replacement options, form-fit-function validation, counterfeit risk and BOM lifecycle management.
18650 battery guide covering lithium-ion cell basics, 3.6V/3.7V voltage, 4.2V charging, mAh and Wh capacity, protected cells, chargers, BMS, series-parallel packs, holders, welding and sourcing checks.…
Hall effect sensor guide covering working principle, linear and digital sensors, Arduino circuits, current sensing, speed detection, automotive applications, A3144 examples, signal filtering and datash…
Product Change Notification guide for electronic components, covering PCN meaning, PCN vs PDN/EOL, common change types, risk levels, form-fit-function review, engineering validation, BOM control, LTB/L…
A practical guide to blend door actuators, covering HVAC function, symptoms, location, AC and heater issues, reset and calibration, replacement cost, electrical diagnosis, compatibility checks, and rep…
Engineering guide to Raspberry Pi alternatives, covering chip-level differences, Orange Pi, ROCK, Jetson, Banana Pi, NanoPi, Compute Module, Pico, GPIO, camera, HAT compatibility, and replacement risks…
