My Inquiry
My Account
Texas Instruments LM2670S-3.3
- Part No.:
- LM2670S-3.3
- Manufacturer:
- Texas Instruments
- Package:
- TO-263-8, D2PAK (7 Leads + Tab), TO-263CA
- Datasheet:
-
LM2670S-3.3.pdf
- Description:
- IC REG BUCK 3.3V 3A TO263
- Quantity:
- Payment:
- Shipping:
Inventory:4,075
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LM2670S-3.3 from Texas Instruments is a monolithic 3-A synchronous step-down (buck) DC/DC voltage regulator with fixed 3.3-V output, 8–40-V input range, 260-kHz internal oscillator, ±2% output tolerance, and 150-mΩ DMOS high-side switch. It delivers high-efficiency power conversion for industrial and communications systems requiring stable 3.3-V rail generation from unregulated DC sources.
For engineers reviewing the LM2670S-3.3 datasheet, LM2670S-3.3 pinout, LM2670S-3.3 application, or LM2670S-3.3 equivalent, key selection criteria include its 3-A continuous output capability, external sync clock support (280–400 kHz), 50-µA shutdown quiescent current, thermal shutdown protection, and compatibility with standard off-the-shelf inductors and Schottky diodes.
Technical Context
The LM2670S-3.3 implements a current-mode PWM control architecture with an integrated 150-mΩ DMOS high-side switch and fixed 260-kHz oscillator. Its feedback loop uses an internal resistive divider for 3.3-V regulation, eliminating external resistor networks. The device supports external synchronization to shift switching frequency above 280 kHz-enabling EMI mitigation and consistent ripple filtering in noise-sensitive radio equipment.
It operates across –40°C to +125°C junction temperature, includes cycle-by-cycle current limiting (3.6–5.4 A), thermal shutdown, and ON/OFF logic-level enable with 1.4-V threshold. The CBOOST pin drives the high-side gate via a 100-nF bootstrap capacitor, ensuring full enhancement of the internal MOSFET for minimal conduction loss.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | Fixed 3.3 V ±2% over full line, load, and temperature (–40°C to 125°C) |
| Input Voltage Range | 8 V to 40 V - supports wide-range industrial and battery-derived supplies |
| Continuous Output Current | 3 A - enables single-regulator solutions for FPGA I/O, microcontroller cores, and peripheral rails |
| Switching Frequency | 260 kHz internal oscillator; externally synchronizable from 280 kHz to 400 kHz for EMI control |
| Efficiency | Up to 94% at 12-V input / 3.3-V output - achieved via low RDS(on) (0.15 Ω) DMOS switch |
| Quiescent Current | 50 µA in shutdown mode - preserves battery life in standby applications |
| Thermal Protection | Integrated thermal shutdown - disables output when junction exceeds safe operating limit |
Pinout & Package
LM2670S-3.3 is available in TO-263 (KTW) and TO-220 (NDZ) packages, both 7-pin surface-mount and through-hole variants with exposed thermal pads. Pin numbering and functions are identical across these packages.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (SW) | Switch output | Drain node of internal high-side DMOS switch; connects to inductor and Schottky diode cathode - carries high-frequency pulsed current |
| 2 (VIN) | Input supply | Main power input (8–40 V); requires low-ESR bypass capacitor placed adjacent to minimize high-frequency noise coupling |
| 3 (CBOOST) | Bootstrap capacitor | Connects 100-nF ceramic capacitor to SW pin to generate gate drive voltage > VIN for full MOSFET enhancement |
| 4 (GND) | Power ground | Common return for input/output capacitors, thermal pad, and internal circuitry - must be low-inductance plane |
| 5 (SYNC) | Sync clock input | Accepts TTL/CMOS clock ≥280 kHz to override internal oscillator; disables current-limit foldback when active |
| 6 (FB) | Feedback | Internally tied to 3.3-V divider - connect directly to output capacitor for fixed-output operation |
| 7 (ON/OFF) | Enable control | Logic-level input: <0.8 V = shutdown (50 µA IQ), >1.4 V = active; internal 20-µA pull-up |
Key Features
| Feature | Design Value |
|---|---|
| Integrated 150-mΩ DMOS switch | Reduces conduction loss and eliminates need for external high-side MOSFET in buck topology |
| Fixed 3.3-V output with ±2% tolerance | Guarantees precise rail compliance for 3.3-V logic, USB peripherals, and Ethernet PHYs without external feedback resistors |
| External sync clock interface (280–400 kHz) | Enables deterministic ripple frequency placement for EMI filtering and coexistence with RF subsystems |
| 50-µA shutdown quiescent current | Supports ultra-low-power sleep modes in portable and always-on industrial controllers |
| Thermal shutdown + cycle-by-cycle current limit | Provides robust fault protection during overload, short-circuit, or inadequate heatsinking conditions |
Applications
| Industrial PLC Power Supply | Communications Baseband Module |
|---|---|
Use Scenario: Generating clean 3.3-V rail from 24-V DC field bus in programmable logic controller backplane. IC Role / Device Role / Timing Role: Primary step-down regulator delivering regulated 3.3-V power to microcontroller, I/O isolators, and CAN transceivers. Use Value: High efficiency (>90% at 24-V input) minimizes heat buildup in enclosed cabinets; ±2% tolerance ensures reliable digital logic operation across temperature extremes. | Use Scenario: Powering baseband processor, ADC/DAC, and memory in LTE small-cell radio unit. IC Role / Device Role / Timing Role: Pre-regulator supplying 3.3-V intermediate rail to LDOs feeding sensitive analog and clock domains. Use Value: External SYNC capability allows alignment of switching frequency to avoid interference with IF bands; 3-A capacity supports burst-mode processing loads. |
| Battery-Powered Test Equipment | Automated Test Fixture Controller |
Use Scenario: Converting 12-V sealed lead-acid battery output to stable 3.3-V for embedded ARM Cortex-M host and sensor interface. IC Role / Device Role / Timing Role: Main system regulator enabling low-noise, high-current operation while preserving battery runtime. Use Value: 50-µA shutdown current extends shelf life and standby duration; wide 8–40-V input accommodates battery voltage sag and charging transients. | Use Scenario: Providing 3.3-V power to FPGA configuration logic, relay drivers, and serial communication ICs in benchtop ATE hardware. IC Role / Device Role / Timing Role: Robust primary DC/DC converter handling variable loads from idle to full actuation sequences. Use Value: Integrated current limiting and thermal protection prevent damage during relay coil inrush or FPGA configuration surges; TO-220 package simplifies heatsinking on test fixture PCBs. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar step-down regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LM2671M-3.3 | Same family, 1-A output rating; smaller SOIC-8 package; identical 3.3-V fixed output and pinout except no SYNC pin | Suitable only for ≤1-A loads; lacks external sync capability - limits EMI control in RF-dense environments | Select when board space is constrained and load current remains below 1 A; verify absence of SYNC requirement. |
| TPS54302DDCR | 3-A synchronous buck with 4.5–28-V input, 3.3-V fixed output, 2.5-V minimum input, and integrated FETs; no external SYNC but offers soft-start and power-good | Lower input voltage limit makes it incompatible with 40-V industrial supplies; lacks thermal pad in SOT-23-6 package | Prefer for compact designs with ≤28-V input and where power-good signaling is required; not drop-in for 40-V systems. |
Compared with LM2671M-3.3 and TPS54302DDCR, the LM2670S-3.3 uniquely supports 40-V maximum input and external clock synchronization - critical for high-voltage industrial and synchronized RF power systems - while maintaining 3-A output and proven thermal performance in TO-263/TO-220 packages.
Availability
LM2670S-3.3 is available at Aetrix Electronics and suitable for industrial automation, communications infrastructure, and battery-powered instrumentation requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.
Supply support for LM2670S-3.3 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
Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and power management ICs, with decades of expertise in high-reliability power conversion solutions.
The LM2670 series belongs to TI's SIMPLE SWITCHER® portfolio - designed specifically for ease-of-use, high-efficiency DC/DC buck conversion using minimal external components and industry-standard magnetics.
FAQ
What is the maximum input voltage rating for LM2670S-3.3?
The LM2670S-3.3 has an absolute maximum input voltage rating of 45 V, with recommended operating range from 8 V to 40 V. Operation beyond 40 V risks exceeding safe operating area limits and may trigger internal protection circuits or cause permanent damage. Always maintain input transient suppression within this envelope for reliable long-term use of the LM2670S-3.3.
Does LM2670S-3.3 require external feedback resistors?
No, the LM2670S-3.3 does not require external feedback resistors. It integrates precision internal resistive dividers calibrated for 3.3-V output, so the FB pin is connected directly to the output capacitor. This eliminates resistor tolerance errors and layout sensitivity, simplifying design and improving regulation accuracy to ±2% across temperature and load for the LM2670S-3.3.
Can LM2670S-3.3 synchronize to an external clock?
Yes, the LM2670S-3.3 supports external synchronization via its SYNC pin (Pin 5). An external TTL/CMOS clock between 280 kHz and 400 kHz can override the internal 260-kHz oscillator. This feature enables precise ripple frequency control for EMI filtering and spectrum management - a key differentiator of the LM2670S-3.3 in RF and communications applications.
What thermal protection features does LM2670S-3.3 include?
The LM2670S-3.3 incorporates thermal shutdown that disables the output when junction temperature exceeds safe limits, plus cycle-by-cycle current limiting (3.6–5.4 A) to prevent destructive overcurrent events. These protections operate independently and are fully integrated - no external components needed. They ensure robust operation under overload, short-circuit, or insufficient heatsinking conditions for the LM2670S-3.3.
Is LM2670S-3.3 compatible with standard off-the-shelf inductors?
Yes, the LM2670S-3.3 is explicitly designed for compatibility with standard off-the-shelf inductors from Renco, Pulse Engineering, and Coilcraft. TI provides inductor selection nomographs and tables based on continuous conduction mode, 30% ripple current target, and validated performance across input/output conditions - enabling rapid, reliable design without custom magnetics for the LM2670S-3.3.
LM2670S-3.3 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- SIMPLE SWITCHER®
- Package/Case:
- TO-263-8, D2PAK (7 Leads + Tab), TO-263CA
- Packaging:
- Tube
- Product Status:
- Obsolete
- Function:
- Step-Down
- Output Configuration:
- Positive
- Topology:
- Buck
- Output Type:
- Fixed
- Number of Outputs:
- 1
- Voltage - Input (Min):
- 8V
- Voltage - Input (Max):
- 40V
- Voltage - Output (Min/Fixed):
- 3.3V
- Voltage - Output (Max):
- -
- Current - Output:
- 3A
- Frequency - Switching:
- 260kHz
- Synchronous Rectifier:
- No
- Operating Temperature:
- -40°C ~ 125°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- TO-263 (DDPAK-7)
LM2670S-3.3 FAQ
1.How can I place an order for LM2670S-3.3 through Aetrix?
Please submit a Request for Quotation (RFQ) for LM2670S-3.3 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 LM2670S-3.3 reliable?
The price and inventory of LM2670S-3.3 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM2670S-3.3 is usually 5 days.
3.What payment methods are accepted for LM2670S-3.3?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM2670S-3.3 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM2670S-3.3?
LM2670S-3.3 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM2670S-3.3 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 LM2670S-3.3?
For technical support, including LM2670S-3.3 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM2670S-3.3 requirements.
6.How does Aetrix verify that LM2670S-3.3 is sourced from the original manufacturer or authorized distributors?
All LM2670S-3.3 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 LM2670S-3.3 meets industry standards.
7.What is the process for return or replacement of LM2670S-3.3?
All LM2670S-3.3 units undergo pre-shipment inspection (PSI). If there is an issue with LM2670S-3.3, 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 LM2670S-3.3 part is unused and in its original packaging.
Return procedure for LM2670S-3.3:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM2670S-3.3 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
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
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…
