LM25011MYX/NOPB - 42V 2A Buck Regulator | Texas Instruments
MPN： LM25011MYX/NOPB ✓ 啟用中LM25011MYX/NOPB 概覽
A buck converter, or step-down regulator, is a DC-DC switching converter that efficiently reduces a higher input voltage to a lower regulated output using a switching element and an LC filter. Unlike linear regulators, buck converters achieve high efficiency even at large input-to-output voltage differences, making them fundamental building blocks in power management IC hierarchies. The LM25011 belongs to the constant on-time regulator family, which regulates by controlling the high-side switch on-time without requiring loop compensation.
Key features include the 6V to 42V input operating range with 45V absolute maximum rating, adjustable output from 2.51V to 40V, and 2A load capability. The COT control scheme provides fast transient response with no external compensation network. An adjustable current limit, set via an external resistor, lets designers tailor the peak switch current, while thermal shutdown protects against fault conditions.
Technically, the on-time is inversely proportional to input voltage, keeping switching frequency nearly constant across the input range. The internal high-side N-channel MOSFET minimizes conduction losses, and a precision feedback comparator ensures accurate regulation up to 2 MHz operation per datasheet specifications.
Typical applications include industrial power supplies, automotive bias rails (with the AEC-Q100 qualified LM25011-Q1 variant), telecom equipment, and 12V/24V distributed bus point-of-load conversion powering microcontrollers and sensors.
Design tip: select the inductor and output capacitor per the datasheet design equations, set the current limit resistor above maximum load current, and use short PCB traces with solid ground planes to minimize parasitic inductance.
直接替換替代品，適用於 LM25011MYX/NOPB — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： LM25011MYX/NOPB （相同外形與佔位） — 差異在於 Current Limit, Operating Temperature, Output Voltage Range, Package, Topology.
LM25011Q1MYX/NOPBQ1
✅ 直接替換📋 參考替代品（不在目錄中）
LM25011QMYX/NOPBQ1
✅ 直接替換聯絡詢價
查看資料表 →LM25011AMYX/NOPB
✅ 直接替換📋 參考替代品（不在目錄中）
LM25011A-Q1MYX/NOPB
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
LM25011MMX/NOPB
⚡ 相同封裝 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
LM25011MYX/NOPB 最大額定值與電氣特性
| 拓撲 | Step-Down (Buck), Constant On-Time |
| 輸入電壓範圍 | 6 V to 42 V |
| Absolute Maximum Input Rating | 45 V |
| 輸出電壓範圍 | 2.51 V to 40 V (adjustable) |
| Output Current | 2 A |
| 輸出數量 | 1 |
| 切換頻率 | Up to 2 MHz |
| Control Scheme | Constant On-Time (COT), no loop compensation required |
| 同步整流器 | No |
| 電流限制 | Adjustable via external resistor |
| Integrated Switch | N-Channel Buck switch |
| 工作溫度 | -40C to +125C |
| 封裝 | HVSSOP (DGQ), 10 pins, 3 mm x 4.9 mm |
| 安裝類型 | Surface Mount |
| Automotive Qualification | LM25011-Q1 variant is AEC-Q100 Grade 1 qualified |
| Protection Features | Thermal shutdown, adjustable current limit, startup regulator |
LM25011MYX/NOPB 腳位配置
| 腳位 1 | VIN — Input supply, 6V to 42V operating range |
| 腳位 2 | SS — Soft-start programming pin |
| 腳位 3 | FB — Feedback input from output voltage divider (1.252V reference) |
| 腳位 4 | AGND — Analog ground reference |
| 腳位 5 | CS — Current limit sense input, sets adjustable current limit via external resistor |
| 腳位 6 | PGND — Power ground for switch current return |
| 腳位 7 | RT — On-time control resistor, sets switching frequency |
| 腳位 8 | SW — Switch node - drain of internal N-channel buck switch |
| 腳位 9 | SW — Switch node (paralleled) |
| 腳位 10 | SD — Shutdown / enable control pin |
| 腳位 EP | Exposed Pad — Ground and thermal dissipation path, must be soldered to PCB copper |
典型應用
LM25011MYX/NOPB 適用於 6 應用s: Industrial 24V Bus Point-of-Load Power, Automotive Bias and Auxiliary Rails, Telecom and Networking Equipment, Battery-Powered Portable Instruments, LED Driver and Lighting Power Supplies, Distributed Microcontroller and Sensor Supplies.
Industrial 24V Bus Point-of-Load Power
Industrial control systems commonly distribute 24V power, and the LM25011MYX/NOPB converts this directly to 5V or 3.3V logic rails at up to 2A without a pre-regulation stage. Its 42V input rating gives headroom above 24V nominal bus transients, and the constant on-time scheme requires no external loop compensation, reducing BOM cost in high-volume PLC and sensor-hub designs. Place the regulator near the load with a compact power stage; the integrated N-channel switch keeps efficiency high while the adjustable current limit can be sized to the specific rail, avoiding overdesign.
推薦
Automotive Bias and Auxiliary Rails
With the AEC-Q100 Grade 1 qualified LM25011-Q1 variant, this regulator family serves automotive auxiliary supplies from 12V or 24V battery buses, powering ECUs, body electronics, and sensor modules. The 45V absolute maximum input absorbs load-dump-adjacent transients in clamped systems, and -40C to +125C junction operation covers underhood and exterior module environments. Because the Q1 variant is pin-to-pin identical to the commercial part, automotive and non-automotive builds can share one PCB layout, simplifying dual-market designs and reducing qualification effort.
推薦
Telecom and Networking Equipment
Telecom infrastructure distributes -48V-derived or 24V intermediate buses, and the LM25011's 6-42V input range and up to 2 MHz capability enable compact, fast-transient buck bias supplies for line cards, DSL modems, and network interface boards. The constant on-time control delivers quick load-transient response without compensation networks - important when rails step-load into processors or PHYs. The adjustable current limit protects against shorted outputs on hot-swappable cards, and the exposed-pad HVSSOP-10 dissipates heat efficiently in convection-cooled rack equipment.
推薦
Battery-Powered Portable Instruments
Portable test instruments and field devices powered by 12V-36V battery packs (lead-acid, Li-ion stacks) use the LM25011MYX/NOPB to generate regulated low-voltage rails efficiently. Wide input tolerance accommodates battery voltage sag and charge-voltage swing without external preregulation, and the COT architecture maintains good light-load behavior for battery-operated duty cycles. Up to 2 MHz operation permits small inductors, shrinking power-stage size for handheld enclosures, while the integrated switch and thermal shutdown simplify safety review for consumer-adjacent designs.
推薦
LED Driver and Lighting Power Supplies
Constant on-time buck topology adapts well to LED bias supplies, and the LM25011's wide 6-42V input covers 12V/24V LED strip and fixture systems. The adjustable current limit supports peak-current-controlled LED drive approaches, and operation up to 2 MHz allows switching above the audible band, avoiding acoustic noise in lighting fixtures. Designers typically regulate LED current by sensing it in the FB path; the device's fast comparator gives responsive dimming behavior. Thermal shutdown provides a fail-safe for enclosed fixtures with limited airflow.
推薦
Distributed Microcontroller and Sensor Supplies
Board-level bias for MCUs, ADCs, and sensors in measurement systems relies on clean, well-regulated local rails. The LM25011MYX/NOPB converts a higher intermediate bus to 3.3V or 5V at up to 2A, and its fast COT transient response supports the step loads of microcontrollers entering and exiting sleep modes. Because it is nonsynchronous with adjustable current limit, designers can safely power crowbar-protected analog sections. Pair with an LDO or ferrite filter for noise-sensitive analog rails in precision data-acquisition chains.
推薦
推薦產品摘要
工程參考資料，適用於 LM25011MYX/NOPB — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | LM25011Q1MYX/NOPBQ1 | LM25011AMYX/NOPB | LM25011MMX/NOPB |
|---|---|---|---|---|
| Package | HVSSOP-10 (DGQ) 3x4.9 mm | HVSSOP-10 (DGQ) - same | HVSSOP-10 (DGQ) - same | MSOP-10 (no power pad) |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Input Voltage Range | 6 V to 42 V | 6 V to 42 V | 6 V to 42 V | 6 V to 42 V |
| Output Current | 2 A | 2 A | 2 A | 2 A |
| Output Voltage Range | 2.51 V to 40 V | 2.51 V to 40 V | 2.51 V to 40 V | 2.51 V to 40 V |
| Automotive Grade (AEC-Q100) | No | Yes (Grade 1) | No | No |
| Low-Dropout High-Frequency Operation | No (standard version) | No | Yes | No |
| Thermal Performance | Exposed power pad (best in family) | Exposed power pad | Exposed power pad | No power pad - higher theta_JA |
主要差異化特點
- Exposed power pad HVSSOP package (對比LM25011MMX/NOPB)
- Automotive AEC-Q100 Grade 1 drop-in option (對比LM25011Q1MYX/NOPBQ1)
- Integrated solution minimizes external parts (對比LM5117PMH/NOPB)
- No loop compensation required (對比LM25011AMYX/NOPB)
設計說明
The HVSSOP-10 (DGQ) exposed pad is the primary heat-removal path for the LM25011. Solder the exposed pad to a grounded copper pour of at least 4-6 via-connected square centimeters; a floating or poorly soldered pad dramatically raises junction temperature at 2A loads from high input voltages. Estimate dissipation as P = Iout^2 x Rds(on) + switching losses plus diode loss, and verify junction temperature stays below 125C at worst-case ambient per the datasheet thermal table.
Keep the SW node, input capacitor, and freewheeling diode loop as small as possible - this high-di/dt loop dominates EMI. Place the input ceramic capacitor within a few millimeters of VIN and PGND, route FB and CS traces away from the switch node, and use the exposed pad as a low-inductance ground reference. Follow the PCB layout example in the TI LM25011 datasheet section on application information for proven component placement.
Set the current-limit resistor on the CS pin above the maximum peak inductor current (load current plus half the ripple), but below the inductor saturation rating - account for tolerance and temperature. Choose the RT on-time resistor so switching frequency stays in the intended range across the 6-42V input, since on-time is inversely proportional to VIN. Use the datasheet design equations rather than copying values between designs, as optimum inductance depends on VIN, VOUT, and frequency.
Never exceed the 45V absolute maximum input rating; add a TVS or input clamp in automotive or industrial environments with load-dump or surge exposure. Do not use the standard LM25011 where duty cycle approaches 100% at high frequency - select the LM25011A variant, which permits low-dropout operation. Also ensure the freewheeling diode is a fast Schottky rated for peak switch current and reverse voltage, not a standard-recovery rectifier.
合規資訊
NOPB suffix indicates No Pull of Bare - lead-free/RoHS-compliant TI packaging convention. AEC-Q100 applies only to the LM25011-Q1 variants, not this commercial part.
