My Inquiry
My Account
Microchip Technology LM2575BU TR
- Part No.:
- LM2575BU TR
- Manufacturer:
- Microchip Technology
- Package:
- TO-263-6, D2PAK (5 Leads + Tab), TO-263BA
- Datasheet:
-
LM2575BU TR.pdf
- Description:
- IC REG BUCK ADJ 1A TO263-5
- Quantity:
- Payment:
- Shipping:
Inventory:3,228
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LM2575BU TR from Micrel is an adjustable-output 1A step-down (buck) switching regulator in TO-263 package, featuring 52kHz fixed-frequency operation, ±2% feedback voltage tolerance, 4V–40V input range, and integrated thermal shutdown and cycle-by-cycle current limiting. It delivers high-efficiency DC/DC conversion for industrial power rails requiring compact, heat-sink-free regulation.
For engineers reviewing the LM2575BU TR datasheet, LM2575BU TR pinout, LM2575BU TR application, or LM2575BU TR equivalent, key selection criteria include guaranteed 1A output current, 52kHz oscillator frequency stability (±10%), ON/OFF control with <200µA standby current, and compatibility with standard off-the-shelf inductors for rapid design implementation.
Technical Context
The LM2575BU TR implements a monolithic buck converter architecture with internal 52kHz oscillator, fixed-gain error amplifier, bandgap reference (1.23V), and 1A NPN switch driver. Its feedback loop monitors output via external resistor divider connected to the FB pin, enabling precise regulation across 1.23V–37V.
Protection functions include thermal shutdown triggered at 150°C junction temperature and peak-current limiting set to 1.7–3.2A. The ON/OFF pin supports logic-level enable/disable with VIH ≥1.4V and VIL ≤1.0V, allowing system-level power sequencing without external circuitry.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Current | Guaranteed 1A continuous load capability with thermal protection |
| Input Voltage Range | 4V to 40V - supports wide-range unregulated DC inputs including automotive and industrial supplies |
| Feedback Voltage | 1.23V ±2% - sets output voltage accuracy when used with external resistive divider |
| Oscillator Frequency | 52kHz ±10% - enables use of low-cost, high-inductance standard inductors (e.g., 330µH) |
| Standby Current | <200µA - enables ultra-low-power shutdown mode for battery-backed systems |
| Saturation Voltage | 1.2V max at 1A - limits conduction loss and improves efficiency under full load |
| Thermal Shutdown | 150°C junction temperature - prevents permanent damage during overload or poor heatsinking |
Pinout & Package
LM2575BU TR uses a 5-pin TO-263 (D²PAK) surface-mount package with exposed thermal pad. Pin 1 is VIN, Pin 2 is OUTPUT, Pin 3 is GND, Pin 4 is FB, and Pin 5 is ON/OFF. The tab is electrically connected to Pin 3 (GND) and serves as primary thermal path.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (VIN) | Input supply connection | Accepts 4V–40V unregulated DC; requires local 100µF input capacitor for EMI suppression |
| 2 (OUTPUT) | Switch node output | Drives external catch diode and inductor; high dI/dt node requiring short PCB trace routing |
| 3 (GND) | Power and signal ground reference | Common return for internal circuitry, thermal pad attachment, and feedback network |
| 4 (FB) | Feedback input | Monitors output via resistor divider; 50nA bias current enables high-impedance voltage setting |
| 5 (ON/OFF) | Enable/disable control | Active-high logic input; <200µA standby current when pulled to 0V |
Key Features
| Feature | Design Value |
|---|---|
| Fixed-frequency oscillator | 52kHz operation simplifies EMI filtering and allows use of low-cost, high-value inductors |
| Internal compensation | Eliminates need for external compensation components-only 4 external parts required |
| Cycle-by-cycle current limit | Protects against short-circuit and overload without latch-up or external sensing |
| Thermal shutdown | Automatically disables output above 150°C junction temperature; resumes after cooldown |
| Adjustable output range | 1.23V to 37V via two-resistor feedback divider-supports custom rail generation |
Applications
| Industrial PLC Power Supply | Automotive Body Control Module |
|---|---|
Use Scenario: Generating stable +5V or +12V from 12V/24V vehicle battery with load transients up to 1A. IC Role / Device Role / Timing Role: Primary buck regulator providing isolated, regulated DC rail for microcontroller and sensor subsystems. Use Value: Eliminates need for heatsink due to 82% typical efficiency at 1A, reducing board space and thermal management complexity. | Use Scenario: Converting 24V truck battery supply to 3.3V for CAN transceiver and MCU logic. IC Role / Device Role / Timing Role: Adjustable-output buck converter configured for 3.3V with tight ±2% feedback tolerance. Use Value: Maintains regulation over wide input range (7V–40V) during cold-crank and load-dump events. |
| Embedded System Pre-regulator | POS Terminal Power Management |
Use Scenario: Stepping down 24V industrial bus to 5V before linear LDO for noise-sensitive analog circuits. IC Role / Device Role / Timing Role: High-efficiency pre-regulator reducing power dissipation in downstream linear regulators. Use Value: Reduces heat sink size by >70% compared to linear solution-critical for sealed enclosures. | Use Scenario: Providing 5V/1A for payment terminal mainboard with ON/OFF control synchronized to host processor. IC Role / Device Role / Timing Role: Enable-controlled buck regulator supporting low-power sleep mode via ON/OFF pin. Use Value: Achieves <200µA standby current, extending battery backup runtime during idle periods. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar buck regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LM2575T-5.0 | Fixed 5V output; TO-220 package; no FB pin; ±3% output tolerance | Requires no external feedback resistors but lacks output flexibility | Select when fixed 5V output suffices and through-hole mounting is preferred |
| MP1584EN-LF-Z | 1.5A rated; 1.5MHz switching frequency; smaller external components; different pinout | Higher frequency enables smaller inductors/capacitors but increases EMI sensitivity | Select for space-constrained designs where 1.5A headroom and compact layout outweigh legacy compatibility needs |
Compared with LM2575T-5.0, the LM2575BU TR offers output adjustability and surface-mount packaging but requires external feedback resistors; versus MP1584EN-LF-Z, it trades higher switching frequency and current rating for proven ruggedness, lower EMI, and simpler magnetics selection in industrial environments.
Availability
LM2575BU TR is available at Aetrix Electronics and suitable for industrial PLC power supplies, automotive body control modules, embedded pre-regulators, POS terminal power management, and on-card switching regulators requiring stable component supply across extended temperature ranges.
Supply support for LM2575BU TR 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
Micrel Inc. was a U.S.-based semiconductor company specializing in analog, power management, and timing solutions before its acquisition by Microchip Technology in 2015.
The LM2575BU TR belongs to Micrel's legacy buck regulator product line, designed for cost-sensitive, high-reliability industrial and automotive DC/DC conversion where simplicity, thermal robustness, and minimal external component count are critical.
FAQ
What is the maximum input voltage rating for LM2575BU TR?
The LM2575BU TR has an absolute maximum input voltage rating of 45V, with recommended operating range up to 40V. Exceeding 40V may compromise long-term reliability and thermal performance. The device maintains regulation across 4V–40V input, making it suitable for 24V industrial buses and automotive applications with transient spikes.
Does LM2575BU TR require an external diode, and what type is recommended?
Yes, LM2575BU TR requires an external Schottky catch diode connected between the OUTPUT pin and GND. The datasheet specifies MBR360 or 1N5822; both provide low forward voltage (<0.55V) and fast recovery to minimize conduction loss and improve efficiency. Diode selection directly impacts thermal performance and ripple behavior.
Can LM2575BU TR be used in negative-output configurations?
Yes, LM2575BU TR supports inverting buck-boost topology to generate negative outputs, such as –5V or –12V, using standard external components. The functional diagram and typical applications section confirm this capability. However, output polarity reversal requires careful PCB layout and component selection to maintain stability and avoid ground loop issues.
What is the thermal resistance (θJA) of LM2575BU TR in its TO-263 package?
The LM2575BU TR in TO-263 (U) package has a junction-to-ambient thermal resistance (θJA) of 45°C/W when mounted on a PCB with approximately 4 square inches of copper area surrounding the leads. This value assumes proper thermal pad soldering and is critical for calculating maximum allowable power dissipation at elevated ambient temperatures.
How does the ON/OFF pin function on LM2575BU TR, and what logic levels activate it?
The ON/OFF pin on LM2575BU TR enables active-high logic control: applying ≥1.4V (min) turns the regulator on, while ≤1.0V (max) forces shutdown with <200µA quiescent current. The pin draws only 4µA typical current when enabled, making it compatible with microcontroller GPIO without level-shifting. Pull-down resistors ensure safe default-off behavior during startup.
LM2575BU TR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- TO-263-6, D2PAK (5 Leads + Tab), TO-263BA
- 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):
- 4V
- Voltage - Input (Max):
- 40V
- Voltage - Output (Min/Fixed):
- 1.23V
- Voltage - Output (Max):
- 37V
- Current - Output:
- 1A
- Frequency - Switching:
- 52kHz
- Synchronous Rectifier:
- No
- Operating Temperature:
- -40°C ~ 125°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- TO-263-5
LM2575BU TR FAQ
1.How can I place an order for LM2575BU TR through Aetrix?
Please submit a Request for Quotation (RFQ) for LM2575BU TR 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 LM2575BU TR reliable?
The price and inventory of LM2575BU TR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM2575BU TR is usually 5 days.
3.What payment methods are accepted for LM2575BU TR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM2575BU TR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM2575BU TR?
LM2575BU TR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM2575BU TR 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 LM2575BU TR?
For technical support, including LM2575BU TR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM2575BU TR requirements.
6.How does Aetrix verify that LM2575BU TR is sourced from the original manufacturer or authorized distributors?
All LM2575BU TR 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 LM2575BU TR meets industry standards.
7.What is the process for return or replacement of LM2575BU TR?
All LM2575BU TR units undergo pre-shipment inspection (PSI). If there is an issue with LM2575BU TR, 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 LM2575BU TR part is unused and in its original packaging.
Return procedure for LM2575BU TR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM2575BU TR 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
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
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…
