LM2675M-3.3/NOPB - 1A, 40V Buck Regulator, 3.3V Fixed | TI
料号： LM2675M-3.3NOPB ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $3.95 | $3.95 |
| 10 | $3.55 | $35.50 |
| 100 | $3.16 | $316.00 |
| 500 | $2.84 | $1,420.00 |
| 1,000 | $2.53 | $2,530.00 |
| 2,500 | $2.31 | $5,775.00 |
LM2675M-3.3NOPB 概述
A buck (step-down) switching regulator is a DC-DC converter that efficiently reduces a higher DC input voltage to a lower DC output voltage by rapidly switching a power transistor and storing energy in an inductor. Buck regulators belong to the broader category of switch-mode power supplies (SMPS), which sit above linear regulators in the power management IC hierarchy. Compared to linear regulators that dissipate the VIN-VOUT differential as heat, switching bucks like the LM2675 deliver high efficiency across wide input ranges, making them ideal for 12V, 24V, and 36V industrial bus systems.
Key features of the LM2675M-3.3/NOPB include 260 kHz fixed switching frequency that enables compact LC filter sizing, internal MOSFET switch, thermal shutdown, cycle-by-cycle current limiting, and a guaranteed ±1.5% output voltage tolerance (with the /NOPB grade). The SOIC-8 package provides adequate thermal performance when copper traces are used as a heatsink, owing to the high efficiency that minimizes internal dissipation.
Architecturally, the LM2675 uses a voltage-mode PWM control loop with a precision bandgap reference and a high-side DMOS power switch monolithically integrated. The 260 kHz operation allows designers to use surface-mount inductors and small ceramic or low-ESR tantalum capacitors, dramatically shrinking the total solution footprint versus 150 kHz predecessors like the LM2596.
Typical applications include 24V industrial sensor rails, distributed 12V-to-3.3V point-of-load (POL) conversion, automotive infotainment subsystems, and battery-powered systems with wide Vin swings. The wide 6.5V to 40V input range makes it well suited for 24V industrial buses and 12V automotive transients. A key design consideration is that the LM2675 is a hard-switching non-synchronous buck — efficiency is very high but ripple requires adequate output capacitance; choose low-ESR capacitors and follow the datasheet's recommended inductor and C_out values for stable operation.
直接替换替代料： LM2675M-3.3NOPB ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
本系列中的变体
可与以下型号直接替换的同系列型号： LM2675M-3.3NOPB （相同外形与封装尺寸） ——差异在于 Efficiency, MSL Level, Operating Temperature Range, Output Voltage, Output Voltage Tolerance.
快速对比工具——选择替代料号进行并排对比：
LM2675M-3.3
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
LM2675MX-3.3/NOPB
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
LM2675M-ADJ/NOPB
✅ 直接替换📋 参考替代料（不在目录中）
LM2674M-3.3/NOPB
✅ 直接替换📋 参考替代料（不在目录中）
LM2674M-ADJ/NOPB
✅ 直接替换📋 参考替代料（不在目录中）
LM2675M-5.0/NOPB
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$1.81 / 个
查看数据手册 →LM2675M-3.3NOPB 最大额定值与电气特性
| 拓扑 | Buck (Step-Down) |
| 输出类型 | Fixed |
| 输出电压 | 3.3 V |
| 最大输出电流 | 1 A |
| 输入电压范围 | 6.5 V to 40 V |
| 开关频率 | 260 kHz |
| 同步整流器 | No |
| 输出数量 | 1 |
| Output Voltage Tolerance | ±1.5% (typical) |
| 效率 | > 90% |
| Internal Switch | Yes (DMOS) |
| 工作温度范围 | -40°C to +125°C |
| 封装 | 8-SOIC (0.154" / 3.90mm width) |
| 安装类型 | Surface Mount |
| RoHS 状态 | Compliant (NOPB suffix) |
| Lead-Free | Yes |
| MSL 等级 | 3 |
LM2675M-3.3NOPB 引脚配置
| 引脚 1 | VIN — Input supply voltage (6.5V to 40V) |
| 引脚 2 | SW — Switch output - connect to inductor |
| 引脚 3 | GND — Ground |
| 引脚 4 | FB — Feedback (not used on -3.3 fixed version, leave open per datasheet) |
| 引脚 5 | CBoost — Bootstrap capacitor for gate drive |
| 引脚 6 | NC — Not connected (per datasheet) |
| 引脚 7 | EN/SYNC — Enable / synchronization pin |
| 引脚 8 | SS — Soft-start control |
典型应用
LM2675M-3.3NOPB 适用于 6 应用s: 24V Industrial Sensor Power Rails, Point-of-Load Conversion from 12V Bus, Automotive Infotainment 12V Subsystems, Battery-Powered Portable Equipment, Distributed POL for FPGA and MCU Cores, Test and Measurement Instrument Rails.
24V Industrial Sensor Power Rails
The LM2675M-3.3/NOPB's 6.5V to 40V input range directly accepts 24V industrial bus voltage, including transient spikes up to 40V, while delivering a regulated 3.3V at 1A to power sensors, ADCs, and isolated transceivers. With >90% efficiency the SOIC-8 part does not need a heatsink in sealed enclosures. Designers benefit from 260 kHz switching which keeps magnetics small, enabling DIN-rail mount form factors. The fixed 3.3V output eliminates external resistor dividers, simplifying BOM for factory-automation modules.
推荐
Point-of-Load Conversion from 12V Bus
The LM2675M-3.3/NOPB is well suited for 12V-to-3.3V point-of-load conversion in distributed power architectures. At 12V input, 3.3V output, and 1A load, efficiency exceeds 90%, minimizing waste heat on dense PCBs. The 260 kHz switching frequency enables tiny surface-mount inductors and ceramic output capacitors. Designers can place the buck regulator near the load to minimize distribution losses, supporting MCUs, FPGAs, and ASIC cores requiring clean 3.3V rails in test equipment, embedded systems, and telecom hardware.
推荐
Automotive Infotainment 12V Subsystems
The LM2675M-3.3/NOPB operates from 6.5V to 40V, comfortably handling 12V automotive bus voltage including load-dump transients up to 40V. The fixed 3.3V output directly powers infotainment MCUs, Bluetooth/Wi-Fi modules, and display controllers at 1A. While not AEC-Q100 qualified, its wide Vin and SOIC-8 footprint are widely deployed in non-safety automotive subsystems. Designers should add input TVS protection for ISO 7637-2 compliance and select low-ESR ceramic output capacitors for stable ripple performance.
推荐
Battery-Powered Portable Equipment
The LM2675M-3.3/NOPB's high efficiency (>90%) makes it suitable for battery-powered portable equipment running from 2-cell to 8-cell battery packs (6V-32V nominal). The wide 6.5V-40V input accepts varying battery voltages as cells discharge or recharge. The 260 kHz switching frequency enables small inductors, supporting compact handheld designs. Designers can use the EN/SYNC pin to enable/disable the regulator during sleep modes, reducing quiescent draw and extending battery life in field instruments and portable diagnostic tools.
推荐
Distributed POL for FPGA and MCU Cores
The LM2675M-3.3/NOPB can deliver 1A at 3.3V to power FPGA I/O banks, MCU core rails, and peripheral logic in distributed POL architectures. The 260 kHz switching frequency minimizes ripple energy in sensitive analog blocks, and the SOIC-8 footprint allows placement near load pins. Pairing the LM2675 with a low-noise LDO post-regulator creates a hybrid power tree optimized for both efficiency (LM2675) and noise (LDO), a common pattern in mixed-signal FPGA designs and high-performance data-acquisition systems.
推荐
Test and Measurement Instrument Rails
The LM2675M-3.3/NOPB's wide Vin range and 1A output capability suit bench-top test and measurement instruments powered from 24V or 36V external supplies. The fixed 3.3V output powers digital logic, ADCs, displays, and communication interfaces with >90% efficiency. The wide operating temperature range (-40°C to +125°C) supports industrial test gear deployed in harsh environments. Designers should follow the datasheet's PCB layout guidelines — short SW trace, grounded output capacitor — to ensure low-EMI operation meeting EN 55011/CISPR 11 limits.
推荐
推荐产品汇总
工程参考数据： LM2675M-3.3NOPB ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | LM2675M-3.3 | LM2675MX-3.3/NOPB | LM2675M-ADJ/NOPB | LM2674M-3.3/NOPB |
|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | 8-SOIC | 8-SOIC - same | 8-SOIC - same | 8-SOIC - same | 8-SOIC - same |
| Output Voltage | 3.3 V fixed | 3.3 V fixed | 3.3 V fixed | Adjustable 1.23V-37V | 3.3 V fixed |
| Output Current | 1 A | 1 A | 1 A | 1 A | 0.5 A |
| Input Voltage Range | 6.5 V to 40 V | 6.5 V to 40 V | 6.5 V to 40 V | 6.5 V to 40 V | 6.5 V to 40 V |
| Switching Frequency | 260 kHz | 260 kHz | 260 kHz | 260 kHz | 260 kHz |
| Efficiency | > 90% | > 90% | > 90% | > 90% | > 90% |
| RoHS / Lead-Free | Yes (NOPB) | No (non-NOPB) | Yes (NOPB) | Yes (NOPB) | Yes (NOPB) |
| Operating Temperature | -40°C to +125°C | -40°C to +125°C | -40°C to +125°C | -40°C to +125°C | -40°C to +125°C |
关键差异点
- 260 kHz switching frequency halves magnetics vs 150 kHz LM2596 （对比 LM2596S-3.3/NOPB)
- Wide 6.5V-40V input covers 12V, 24V, and 36V industrial buses （对比 LM2674M-3.3/NOPB)
- Fixed 3.3V output eliminates external feedback resistors （对比 LM2675M-ADJ/NOPB)
设计说明
Place the input bypass capacitor (≥10 µF, low-ESR) as close as possible to the VIN pin and ground. Keep the SW trace short and wide to minimize EMI and parasitic inductance. The output capacitor (≥68 µF low-ESR tantalum or ceramic) must be placed close to the load to reduce voltage ripple. Per the TI LM2675 datasheet, a ground plane is essential; the feedback trace (if used on ADJ version) should be routed away from the SW trace to avoid noise coupling.
Although the LM2675 achieves >90% efficiency, at maximum VIN (40V) and full 1A load with VOUT=3.3V, internal dissipation can reach roughly 1-2W. The SOIC-8 package relies on copper traces as heatsinking — design at least 1 square inch of 2-oz copper on the GND pin and a copper pour under the exposed SW trace to keep junction temperature below 125°C. For higher ambient temperatures, calculate theta_JA from the TI datasheet thermal table; thermal shutdown engages at ~165°C, which is far above reliable operating limits.
Do not exceed 40V on VIN — load-dump transients in automotive systems can exceed this and damage the part; add a TVS or input clamp. Avoid operating below 6.5V on VIN, as the internal regulator will drop out. Use only low-ESR capacitors as specified in the datasheet; high-ESR electrolytics will cause instability. On the fixed -3.3V variant, leave the FB pin unconnected — connecting it can introduce noise. Finally, respect the minimum load current specified in the datasheet for proper regulation.
合规信息
RoHS compliant per /NOPB suffix. Not AEC-Q100 qualified; for automotive safety applications, choose AEC-Q100 qualified regulators. Lead-free per TI product page.
