LM3671QMFX
Synchronous Step-Down DC-DC ConverterThe LM3671QMFX is a synchronous step-down dc-dc converter from Texas Instruments. View the full LM3671QMFX datasheet below including key specifications, electrical characteristics, absolute maximum ratings.
LM3671QMFX shares its datasheet with LM3671MFX-3.3, whose page lists every part number it covers.
Official LM3671QMFX datasheet (PDF) — the source this page was extracted from.
LM3671QMFX Key Specifications
| Parameter | Value |
|---|---|
| Protection | Current overload, thermal shutdown, under-voltage |
| Qualification | AEC-Q100 Grade 1 |
| Output Voltage | 1.2V (fixed) |
| Shutdown Current | 0.01µA (typ.) |
| Quiescent Current | 16µA (typ.) in PFM mode |
| Package Dimensions | 2.92mm x 2.84mm x 1.2mm (SOT-23 DBV) |
| Input Voltage Range | 2.7V to 5.5V |
| Switching Frequency | 2MHz (typ.) in PWM mode |
| Maximum Load Current | 600mA |
| Internal Reference Voltage | 0.5V |
| Operating Junction Temperature | -40°C to +125°C |
| Ambient Temperature Range (Q-Grade) | -40°C to +125°C |
LM3671QMFX Overview
Part: LM3671MFX-3.3 (LM3671 / LM3671-Q1 family) — Texas Instruments
Type: Synchronous Step-Down (Buck) DC-DC Converter
Description: 2.7–5.5 V input, 600 mA step-down DC-DC converter with 2 MHz typical fixed PWM switching frequency, automatic PFM/PWM switching, and 16 μA typical quiescent current.
Operating Conditions:
- Supply voltage: 2.7–5.5 V
- Operating temperature: -40 to 85 °C ambient (junction -40 to 125 °C)
- Recommended load current: 0–600 mA
- Switching frequency: 2 MHz typical (PWM mode)
Absolute Maximum Ratings:
- VIN pin voltage to GND: -0.2 to 6 V
- FB, SW, EN pins: GND - 0.2 V to VIN + 0.2 V
- Max junction temperature (TJ-MAX): 125 °C
- Storage temperature: -65 to 150 °C
- Max lead temperature (soldering): 260 °C
Key Specs:
- Feedback voltage accuracy (fixed, MF version): ±4% (PWM mode, -40 to 125 °C)
- Internal reference voltage: 0.5 V typical
- Shutdown supply current: 0.01 μA typical, 1 μA max (EN = 0 V, -40 to 125 °C)
- Quiescent current (no load, not switching): 16 μA typical, 35 μA max (-40 to 125 °C)
- PFET RDS(on): 380 mΩ typical, 500 mΩ max (VIN = VGS = 3.6 V)
- NFET RDS(on): 250 mΩ typical, 400 mΩ max (VIN = VGS = 3.6 V)
- Switch peak current limit: 830 mA min, 1020 mA typical, 1150 mA max (open loop)
- Oscillator frequency: 1.6 MHz min, 2 MHz typical, 2.6 MHz max
- Line regulation: 0.031 %/V typical; load regulation: 0.0013 %/mA typical
- EN logic thresholds: high ≥ 1 V, low ≤ 0.4 V
Features:
- Automatic PFM-PWM mode switching
- Internal synchronous rectification for high efficiency
- Internal soft start
- Current overload and thermal shutdown protection
- Operates from a single Li-Ion cell
- Only three external components required (one inductor, two ceramic capacitors)
- Fixed output voltage and adjustable (1.1–3.3 V) versions available
- LM3671-Q1 is AEC-Q100 qualified (Grade 1: -40 to +125 °C ambient)
Applications:
- Mobile phones
- PDAs
- MP3 players
- W-LAN
- Portable instruments
- Digital still cameras
- Portable hard disk drives
- Automotive
- Portable medical equipment
- Handheld transaction terminals
- Wireless home-automation equipment
Package:
- USON (6): 2.00 mm × 2.00 mm (NOM)
- SOT-23 (5): 2.90 mm × 1.60 mm (NOM)
- DSBGA (5): 1.413 mm × 1.083 mm (MAX)
LM3671QMFX Features
- 1 · LM3671-Q1 is Qualified for Automotive Applications
- AEC Q100-Qualified With the Following Results
- -Device Temperature Grade 1: -40°C to +125°C Ambient Operating Temperature Range
- 16-μA Typical Quiescent Current
- 600-mA Maximum Load Capability
- 2-MHz PWM Fixed Switching Frequency (Typical)
- Automatic PFM-PWM Mode Switching
- Internal Synchronous Rectification for High Efficiency
- Internal Soft Start
- 0.01-μA Typical Shutdown Current
- Operates from a Single Li-Ion Cell Battery
- Only Three Tiny Surface-Mount External Components Required (One Inductor, Two Ceramic Capacitors)
- Current Overload and Thermal Shutdown Protection
- Available in Fixed Output Voltages and Adjustable Version
LM3671QMFX Applications
- Mobile Phones
- PDAs
- MP3 Players
- W-LAN
- Portable Instruments
- Digital Still Cameras
- Portable Hard Disk Drives
- Automotive
- Portable Medical Equipment
- Handheld Transaction Terminals
- Wireless Home-Automation Equipment
LM3671QMFX Pin Configuration
DBV Package 5 Pin SOT-23 Top View
LM3671QMFX Electrical Characteristics
Unless otherwise noted, limits apply for for T J = 25°C, and specifications apply to the LM3671MF/TL/LC with VIN = EN = 3.6 V (1)(2)(3)
| PARAMETER | PARAMETER | TEST CONDITION | MIN | TYP | MAX | UNIT |
|---|---|---|---|---|---|---|
| V IN | Input voltage Feedback voltage (fixed) MF | - 40°C to 125°C, see (4) | 2.7 - 4% | 5.5 4% | V | |
| Feedback voltage (fixed) TL Feedback voltage (fixed) LC | PWM mode (5) , - 40°C to 125°C | - 2.5% - 4% | 2.5% 4% | |||
| V FB | Feedback voltage (ADJ) MF (6) | (5) | - 4% | 4% | ||
| Feedback voltage (ADJ) TL | PWM mode , - 40°C to 125°C | - 2.5 | 2.5 | |||
| Line regulation | 2.7 V ≤ V IN ≤ 5.5 V, I O = 10 mA | 0.031 | %/V | |||
| Load regulation | 100 mA ≤ I O ≤ 600 mA, V IN = 3.6 V | 0.0013 | %/mA | |||
| V REF | Internal reference voltage | 0.5 | V | |||
| I SHDN | Shutdown supply current | EN = 0 V EN = 0 V, - 40°C to 125°C | 0.01 | 1 | μA | |
| I | DC bias current into V | No load, device is not switching (FB forced higher than programmed output voltage) | 16 | |||
| Q | IN | No load, device is not switching (FB forced higher than programmed output voltage), - 40°C to 125°C | 35 | μA | ||
| R DSON (P) | Pin-pin resistance for PFET | V IN = V GS = 3.6 V | 380 | 500 | m Ω | |
| R DSON (N) | Pin-pin resistance for NFET | V IN = V GS = 3.6 V | 250 | 400 | m Ω | |
| I LIM | Switch peak current limit | Open loop (7) Open loop (7) , - 40°C to 125°C | 830 | 1020 | 1150 | mA |
| V | - 40°C to 125°C | 1 | V V | |||
| V IH | Logic high input | 0.4 | ||||
| IL | Logic low input | - 40°C to 125°C | ||||
| I | Enable (EN) input current | 0.01 | μA | |||
| EN | - 40°C to 125°C | 1 | ||||
| ƒ OSC | Internal oscillator frequency | PWM Mode (5) PWM Mode (5) , - 40°C to 125°C | 1.6 | 2 | 2.6 | MHz |
LM3671QMFX Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted) (1)(2)
| MIN | MAX | UNIT | |
|---|---|---|---|
| V IN pin: voltage to GND | - 0.2 | 6 | V |
| FB, SW, EN pins | GND - 0.2 | V IN + 0.2 | V |
| Continuous power dissipation (3) | Internally Limited | Internally Limited | |
| Junction temperature, T J-MAX | 125 | °C | |
| Maximum lead temperature (soldering, | 260 | °C | |
| Storage temperature, T stg | -65 | 150 | °C |
LM3671QMFX Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted) (1)(2)
| MIN | MAX | UNIT | |
|---|---|---|---|
| Input voltage (3) | 2.7 | 5.5 | V |
| Recommended load current | 0 | 600 | mA |
| Junction temperature, T J | -40 | 125 | °C |
| Ambient temperature, T A (4) | -40 | 85 | °C |
LM3671QMFX Thermal Information
| THERMAL METRIC (1) | LM3671 - NKH (USON) - 6 PINS | LM3671 and LM3671-Q1 - DBV (SOT-23 ) - 5 PINS | LM3671 and LM3671-Q1 - YZR (DSBGA) - 5 PINS | UNIT | |
|---|---|---|---|---|---|
| R θ JA | Junction-to-ambient thermal resistance | 174.7 | 165.7 | 181.0 | °C/W |
| R θ JC(top) | Junction-to-case (top) thermal resistance | 87.1 | 116.6 | 0.9 | °C/W |
| R θ JB | Junction-to-board thermal resistance | 109.0 | 26.8 | 110.3 | °C/W |
| ψ JT | Junction-to-top characterization parameter | 6.4 | 13.3 | 7.4 | °C/W |
| ψ JB | Junction-to-board characterization parameter | 109.0 | 26.3 | 110.3 | °C/W |
LM3671QMFX Typical Application
LM3671, LM3671-Q1
SNVS294S -NOVEMBER 2004-REVISED MAY 2016
Variants on the same datasheet
These parts have exact links to the same datasheet. They are candidates to compare, not verified drop-in replacements; check package, pinout and electrical limits.
| Part Number | Manufacturer | Package |
|---|---|---|
| LM3671 | Texas Instruments | — |
| LM3671MFX-3.3 | Texas Instruments | SOT-23 |
Other Switching Regulators (Buck)
- TPS54302 – Texas Instruments, Synchronous Step-Down Converter
- MAX20730 – Analog Devices, Synchronous Switching Regulator
- TLV62568 – Texas Instruments, Synchronous Buck Converter
- LM2596 – Texas Instruments, Step-Down Voltage Regulator
- TPS562200 – Texas Instruments, Synchronous Buck Converter
- AP63203WU – Diodes Incorporated, Synchronous Buck Converter
- AP63357DV-7 – Diodes Incorporated, Synchronous Buck Converter
- LMR38010FDDAR – Texas Instruments, Synchronous Buck Converter
All Switching Regulators (Buck) datasheetsAll Texas Instruments datasheets (2,418)
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