LMR14050SDDA - 40V 5A 2.2MHz Buck Converter | Texas Instruments
MPN: LMR14050SDDA β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.25 | $3.25 |
| 10 | $2.92 | $29.20 |
| 100 | $2.48 | $248.00 |
| 500 | $2.11 | $1,055.00 |
| 1,000 | $1.82 | $1,820.00 |
LMR14050SDDA Overview
A step-down converter (buck regulator) is a switching voltage regulator that converts a higher input voltage to a lower output voltage using a switching element, inductor, and capacitors. Buck regulators sit within the power management IC hierarchy and offer far higher efficiency than linear regulators, making them the default choice for wide-input industrial and automotive power conditioning.
Key features include the 40 uA quiescent sleep-mode current and 1 uA shutdown current for battery-powered designs, an adjustable switching frequency up to 2.2 MHz (RT/SYNC pin) allowing operation above the AM band, internal loop compensation that minimizes external component count, and pulse-skipping eco-mode at light loads for high efficiency across the load range.
Technically, the LMR14050 integrates a high-side MOSFET rated for the full 40 V input transient environment, with cycle-by-cycle current limiting, thermal shutdown, and a power-good output flag for rail supervision. The constant-on-time control topology delivers fast transient response and eases compensation across a wide range of output capacitance values.
Typical applications include 12 V and 24 V industrial bus power conditioning, automotive battery-front-end pre-regulators feeding downstream point-of-load converters, and battery-powered instrumentation where 40 uA standby current preserves battery life.
Design consideration: at 2.2 MHz switching frequency, inductor and capacitor values shrink, but the input voltage ripple and switching losses rise; choose the RT resistor per the datasheet equations and verify thermal performance on the PowerPAD copper pour.
This page synthesizes verified distributor data, same-family drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for LMR14050SDDA 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 LMR14050SDDA (same form factor and footprint) β differing in Maximum Output Current, Output Voltage Range, Package, Topology.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
LMR14050SQDDAQ1
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
LMR14030SDDA
β Drop-In β οΈ εζ°εΎ ιͺθ―β In Stock
$1.58 / Unit
View Datasheet βLMR14020SDDA
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
LMR14030SQDDAQ1
β Drop-Inπ Reference alternative (not in catalog)
LMR14050SDDA Maximum Ratings & Electrical Characteristics
| Topology | Buck (Step-Down) DC-DC Converter |
| Input Voltage Range | 4 V to 40 V |
| Output Voltage Range | 0.8 V to 28 V (adjustable) |
| Maximum Output Current | 5 A |
| Switching Frequency | Adjustable, up to 2.2 MHz |
| Quiescent Current (Sleep Mode) | 40 uA |
| Shutdown Current | 1 uA |
| Number of Outputs | 1 |
| Output Type | Positive, Adjustable |
| Integrated MOSFET | High-side MOSFET integrated |
| Package | HSOIC-8 (DDA, SO-PowerPAD-8), 3.90 mm width |
| Operating Temperature | -40C to +125C |
| Mounting Type | Surface Mount |
| Control Topology | Constant on-time with internal compensation |
| Protection Features | Cycle-by-cycle current limit, thermal shutdown, power-good flag |
| Product Family | SIMPLE SWITCHER LMR140x0 |
LMR14050SDDA Pin Configuration
| Pin 1 | BOOT β Bootstrap capacitor connection for high-side gate driver (capacitor from BOOT to SW) |
| Pin 2 | VIN β Input supply voltage, 4 V to 40 V; decouple with ceramic capacitor to GND |
| Pin 3 | EN β Enable input; pull high to enable, low disables regulator (1 uA shutdown) |
| Pin 4 | RT/SYNC β Switching frequency set resistor or external synchronization clock input |
| Pin 5 | GND β Ground reference; connect to exposed PowerPAD and PCB ground plane |
| Pin 6 | FB β Feedback input from output voltage divider; reference 0.8 V sets output |
| Pin 7 | PWRGD β Power-good open-drain output flag indicating output in regulation |
| Pin 8 | SW β Switch node; connect to power inductor, keep loop area minimal |
Typical Applications
LMR14050SDDA is suitable for 6 applications: Industrial 24V Bus Power Conditioning, Automotive Battery Front-End Pre-Regulator, Battery-Powered Instrumentation, Point-of-Load Conversion for FPGAs and DSPs, LED Lighting and Display Power, Communications and Networking Equipment.
Industrial 24V Bus Power Conditioning
The LMR14050SDDA fits 24 V industrial bus systems because its 40 V input rating survives surges well above the nominal 24 V rail, while delivering up to 5 A for controllers, sensors, and I/O modules. The adjustable 0.8 V to 28 V output range covers both intermediate 12 V/5 V rails and point-of-load 3.3 V/1.8 V supplies. Placed directly after the input protection stage with a suitable inductor and ceramic output capacitors, its constant on-time control gives fast transient response to motor-start and relay-switching load steps, and its 40 uA sleep IQ benefits always-on monitoring nodes.
Recommended
Automotive Battery Front-End Pre-Regulator
Automotive 12 V battery rails experience load-dump transients that demand a wide input range; the LMR14050SDDA's 4 V to 40 V input with integrated high-side MOSFET handles cold-crank and transient conditions from unregulated sources. It can pre-condition the battery rail down to a stable intermediate bus feeding point-of-load converters, or directly power 5 A-class loads such as LED drivers and infotainment audio rails. For AEC-Q100-qualified programs, pair the design with the LMR14050SQDDAQ1 variant, which shares the identical HSOIC-8 (DDA) footprint so one layout serves both commercial and automotive builds.
Recommended
Battery-Powered Instrumentation
The LMR14050SDDA suits battery-powered systems because it draws only 40 uA quiescent current in sleep mode and 1 uA in shutdown, preserving battery life during long idle intervals in portable test equipment, dataloggers, and wireless sensor nodes. When the load wakes, the converter ramps to the full 5 A capability, so one regulator serves both standby and peak modes. The RT/SYNC pin lets designers set switching frequency above 400 kHz to keep switching artifacts away from sensitive measurement bands, and the PWRGD output gives the microcontroller a supervisory flag for safe power-up sequencing.
Recommended
Point-of-Load Conversion for FPGAs and DSPs
High-performance processors require tightly regulated low-voltage rails with fast transient response; the LMR14050SDDA's 5 A output and adjustable output down to 0.8 V directly serve 1.0 V to 1.8 V core and I/O rails for FPGAs and DSPs from a 12 V or 24 V intermediate bus. Internal loop compensation reduces design effort and allows moderate output capacitance while maintaining stability. Setting the switching frequency near 2.2 MHz keeps the inductor small, important in dense compute boards, though designers should verify thermal margin since higher frequency increases switching losses in the integrated high-side MOSFET.
Recommended
LED Lighting and Display Power
Industrial and signage LED fixtures are often fed from rectified or unregulated DC sources where the voltage can swing widely; the LMR14050SDDA converts such sources to a stable constant-voltage bus powering LED driver circuits. The 40 V maximum input covers 24-36 V lighting buses, and 5 A output supports multi-string arrays. Because the regulator skips pulses at light load for efficiency, dimmed or partially loaded fixtures waste less standby power. Layout should follow the datasheet PowerPAD recommendations and keep the SW-node loop compact to minimize radiated EMI from fast switching edges.
Recommended
Communications and Networking Equipment
Routers, switches, and base-station accessories commonly run from -48 V-derived or 24 V intermediate buses; the LMR14050SDDA steps such rails down to 5 V or 3.3 V system supplies with up to 5 A capacity. Its 2.2 MHz maximum switching frequency allows filtering well above sensitive radio bands, easing EMC compliance in RF-adjacent equipment, while eco-mode light-load pulsing keeps efficiency high during low-traffic periods. The wide 4 V input floor also tolerates brown-out conditions on distributed power, and the PWRGD flag simplifies system-level sequencing with downstream controllers and network processors.
Recommended
Recommended Products Summary
Engineering reference data for LMR14050SDDA β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | LMR14050SQDDAQ1 | LMR14030SDDA | LMR14020SDDA |
|---|---|---|---|---|
| Package | HSOIC-8 (DDA, SO-PowerPAD-8) | HSOIC-8 (DDA) - same | HSOIC-8 (DDA) - same | HSOIC-8 (DDA) - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Maximum Output Current | 5 A | 5 A | 3.5 A | 2 A |
| Input Voltage Range | 4 V to 40 V | 4 V to 40 V | 4 V to 40 V | 4 V to 40 V |
| Output Voltage Range | 0.8 V to 28 V | 0.8 V to 28 V | 0.8 V to 28 V | 0.8 V to 28 V |
| Quiescent Current (Sleep) | 40 uA | 40 uA | 40 uA | 40 uA |
| Max Switching Frequency | 2.2 MHz | 2.2 MHz | 2.2 MHz | 2.2 MHz |
| Automotive Grade (AEC-Q100) | No | Yes (Q1 variant) | No | No |
Key Differentiators
- Full 5 A output in compact 8-pin package (vs LMR14030SDDA)
- Ultra-low 40 uA standby current (vs LMR14050SQDDAQ1)
- Wide 40 V input survivability (vs LMR14020SDDA)
Design Notes
The exposed PowerPAD under the HSOIC-8 (DDA) package is the primary thermal path and must be soldered to a stitched ground plane array of thermal vias. Keep the SW node (pin 8), BOOT capacitor, and input capacitor loop as compact as possible to minimize parasitic ringing at the switching edge. At 2.2 MHz operation, place a small RC snubber across SW-to-GND if radiated emissions testing shows peak ringing above 200 MHz.
Estimated: at VIN=24 V, VOUT=5 V, IOUT=5 A, efficiency of roughly 90% (per datasheet curves) implies about 2.8 W of loss inside the IC and inductor. Verify the junction-to-ambient thermal resistance on your PCB stackup keeps TJ below 125C. Increasing RT-set switching frequency reduces efficiency roughly proportionally to switching losses - trade frequency down when thermal margin is tight.
Do not exceed the 40 V absolute maximum input rating; automotive load-dump conditions require a TVS clamp upstream. The FB divider must use 1% or better resistors to hold output accuracy on the 0.8 V reference. Ensure the EN pin is not left floating in noisy environments - tie it through a divider for undervoltage lockout behavior. Omitting the bootstrap capacitor on pin 1 will prevent the high-side MOSFET from switching at all.
Compliance Information
RoHS compliant per distributor listings (DigiKey/Mouser). Not AEC-Q100 qualified - use LMR14050SQDDAQ1 for automotive. REACH/halogen details not stated in provided data.
