LP38692MPX-3.3/NOPB - 1A 3.3V LDO SOT-223-5 | Texas Instruments
料号： LP38692MPX-3.3/NOPB ✓ 量产中LP38692MPX-3.3/NOPB 概述
A low-dropout (LDO) regulator is a type of linear voltage regulator that maintains a regulated output even when the input voltage is only slightly above the desired output voltage. LDOs sit in the broader hierarchy of voltage regulators under the power-management IC category, and unlike switching regulators they generate no switching ripple, trading efficiency for exceptionally clean output. The LP38692 family is designed for direct operation from a single-cell Li-ion or 9 V wall-adapter rail and is stable with low-ESR ceramic output capacitors, eliminating the need for bulky tantalum or polymer bulk capacitors in space-constrained designs.
Key features include 1 µA off-state quiescent current, 55 µA typical ground-pin current at full load, thermal overload protection, and foldback current limiting. The active-high enable pin (LP38692 vs. LP38690 which lacks EN) supports sub-1 µA shutdown, making the part well-suited for battery-powered systems. The CMOS process plus a precision trimmed bandgap reference gives tight line and load regulation across the -40 °C to +125 °C operating range.
The LP38692 uses a PMOS pass element architecture that minimizes ground current and provides inherent short-circuit protection through foldback limiting. With a low thermal resistance SOT-223 footprint (~50 °C/W on a 1-oz copper pour), the part can deliver the full 1 A continuously without an external heatsink in most applications. Ceramic output-capacitor stability simplifies BOM and supports small case-size X5R/X7R ceramics directly at the load.
Typical end-products include USB-powered peripherals, single-cell Li-ion portable electronics, 5 V to 3.3 V post-regulation after a switching converter, set-top boxes, solid-state drives, white goods, and industrial sensors. The wide input range also makes it ideal as a post-regulator following a 5 V or 9 V system rail.
When designing with this part, place input/output ceramics within 1-2 mm of the device pins, keep the trace to the SOT-223 tab as wide as practical for heat spreading, and respect the 10 V absolute maximum input rating to avoid device damage during transients.
This page synthesizes distributor pricing, drop-in alternatives within the LP3869x family, and practical thermal/layout design notes beyond what the manufacturer datasheet provides alone.
直接替换替代料： LP38692MPX-3.3/NOPB ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
LP38690MPX-3.3/NOPB
✅ 直接替换📋 参考替代料（不在目录中）
LP38692MPX-3.3
✅ 直接替换📋 参考替代料（不在目录中）
LP38692MP-3.3/NOPB
✅ 直接替换📋 参考替代料（不在目录中）
LP38692MPX-5.0/NOPB
✅ 直接替换📋 参考替代料（不在目录中）
LP38692MPX-2.5/NOPB
✅ 直接替换📋 参考替代料（不在目录中）
LP38692MPX-3.3/NOPB 最大额定值与电气特性
| Regulator Type | LDO (Low-Dropout) Linear Regulator |
| 输出类型 | Fixed |
| 输出电压 | 3.3 V |
| 输出电流（最大） | 1 A |
| 输入电压范围 | 2.7 V to 10 V |
| Dropout Voltage (Typ @ 1 A, VOUT=5 V) | 450 mV |
| Output Accuracy (25 °C) | ±2.5% |
| Quiescent Current (Off-State) | 1 µA |
| Ground Pin Current (Typ, Full Load) | 55 µA |
| 工作温度范围 | -40 °C to +125 °C |
| 封装 | SOT-223-5 (NDC) 4 leads + Tab |
| 安装类型 | Surface Mount |
| Output Capacitor Stability | Stable with low-ESR ceramic capacitors |
| 使能引脚 | Yes (active-high) |
| Protection Features | Thermal Overload, Foldback Current Limit |
| RoHS / Lead-Free | RoHS Compliant, Lead-Free (NOPB finish) |
LP38692MPX-3.3/NOPB 引脚配置
| 引脚 1 | IN — Input voltage supply (2.7 V to 10 V) |
| 引脚 2 | GND — Ground reference |
| 引脚 3 | EN — Enable input (active-high, internal pull-up) |
| 引脚 4 | NC — Not connected (fixed-output version; ADJ on adjustable variants) |
| 引脚 5 | OUT — Regulated 3.3 V output |
| 引脚 Tab | GND/Thermal Pad — Electrically tied to GND (pin 2); solder to PCB copper for heatsinking |
典型应用
LP38692MPX-3.3/NOPB 适用于 6 应用s: 5V to 3.3V Post-Regulation After Switching Converter, Single-Cell Li-Ion Portable Device Power Rail, USB-Powered Peripheral 3.3V Rail, Industrial Sensor and PLC Logic Supply, Solid-State Drive (SSD) and Storage Controller Power, Set-Top Box and Home Appliance Logic Supply.
5V to 3.3V Post-Regulation After Switching Converter
The LP38692MPX-3.3/NOPB is ideal as a clean post-regulator following a 5 V or 9 V switching converter. Its 2.7-10 V input tolerates a wide range of upstream rails, and its LDO architecture adds no switching ripple, suppressing high-frequency noise from the buck converter that would otherwise reach sensitive downstream 3.3V loads. At 1 A and 3.3 V output from a 5 V rail, dissipation is approximately 1.7 W, manageable on the SOT-223 tab with a 1 square-inch copper pour. The 450 mV dropout at 1 A leaves 1.7 V of headroom from 5 V, ensuring regulation across temperature. Use a 10 µF X7R ceramic at input and output, placed within 2 mm of the pins, for stable operation. Companion parts include TI TPS54302 (buck stage), TI TPS7A4515 (additional LDO rail), and TI MSP430 microcontrollers that commonly run from 3.3 V.
推荐
Single-Cell Li-Ion Portable Device Power Rail
The LP38692MPX-3.3/NOPB suits battery-powered portable designs powered from a single-cell Li-ion source (3.0-4.2 V). Its 2.7 V minimum input accepts the Li-ion end-of-discharge voltage, while the 10 V maximum handles inadvertent transients from USB chargers. The 1 µA off-state quiescent current when EN is pulled low extends battery shelf life in storage and shipping. CMOS architecture keeps full-load ground current at 55 µA, preserving battery runtime. The active-high EN pin interfaces directly to a microcontroller GPIO for software-controlled shutdown. Typical loads include low-power MCUs, BLE radios, and display drivers running from 3.3 V. The SOT-223-5 footprint occupies just 6.5 mm x 3.5 mm of board area, smaller than comparable DPAK alternatives. Recommended companion MPNs: TI CC2640 (BLE SoC) and TI MSP430G2553 (low-power MCU), both of which operate natively from 3.3 V.
推荐
USB-Powered Peripheral 3.3V Rail
The LP38692MPX-3.3/NOPB generates a stable 3.3 V rail directly from a USB-derived 5 V bus in peripherals such as HID devices, communication dongles, and test fixtures. The 2.7-10 V input range tolerates USB bus voltage droops and surges, while the 1 A continuous output supports peripherals that need to source 3.3 V at up to several hundred mA plus a downstream MCU and logic. The 450 mV dropout at 1 A leaves ample margin from a nominal 5 V USB rail. Low-ESR ceramic output-capacitor stability eliminates the need for bulky tantalum capacitors in slim USB stick form factors. Thermal shutdown protects against short-circuit faults on the 3.3 V rail without damage to the regulator. The /NOPB lead-free finish satisfies USB-IF and consumer-electronics RoHS requirements. Companion: TI TUSB32001 (USB Type-C controller) and TI MSP430F5529 (USB microcontroller) for USB peripherals.
推荐
Industrial Sensor and PLC Logic Supply
In industrial 24 V-bus systems, the LP38692MPX-3.3/NOPB can drop directly to 3.3 V via a pre-regulator, but is even more commonly used after a 5 V or 9 V intermediate rail. Its wide -40 °C to +125 °C operating range handles factory-floor temperature extremes, and its thermal overload plus foldback current limit provide fault tolerance in harsh environments. The SOT-223-5 tab provides a robust solder joint that survives industrial shock and vibration testing. Low quiescent current (55 µA typical at full load) minimizes self-heating in sealed enclosures. Typical loads include 4-20 mA loop converters, Modbus transceivers, and sensor signal-conditioning front-ends. The device's fixed 3.3 V output reduces BOM count versus an adjustable LDO with external resistor divider. Companion: TI ISO1541 (I2C isolator) and TI ADS1115 (16-bit ADC for sensor readout).
推荐
Solid-State Drive (SSD) and Storage Controller Power
The LP38692MPX-3.3/NOPB provides a clean 3.3 V rail for NAND flash controllers, DRAM, and SSD housekeeping logic in storage designs. Its LDO architecture eliminates switching noise that could couple into high-speed NAND interfaces, supporting reliable data transfer at multi-gigabit rates. The 1 A output current handles the peak demands of controller bursts plus memory housekeeping. The wide 2.7-10 V input accepts the 5 V or 12 V system rails after a pre-regulator stage. Low off-state quiescent current (1 µA with EN low) supports SSD sleep states with minimal battery drain in mobile storage. Thermal shutdown and foldback current limit protect against short circuits in densely populated SSD PCBs. Companion: TI TPS22918 (load switch) and TI TPS54331 (3.3 V main rail switching converter).
推荐
Set-Top Box and Home Appliance Logic Supply
The LP38692MPX-3.3/NOPB supplies 3.3 V logic in set-top boxes, white goods, and home appliances where reliability over a 5-15 year product lifetime matters. The CMOS architecture's lack of moving charge pumps and the bandgap reference's trimmed accuracy yield excellent output endurance, eliminating periodic re-calibration. Wide operating temperature (-40 °C to +125 °C) covers appliance interior temperatures near heating elements. The SOT-223-5 (NDC) tab provides robust mechanical soldering for high-volume automated assembly. Fixed 3.3 V output reduces BOM count versus adjustable LDOs in cost-sensitive appliance designs. The /NOPB finish satisfies consumer-electronics RoHS requirements. Typical loads include the main SoC, HDMI interface, and remote-control receiver. Companion: TI MSP432P401R (low-power ARM MCU) and TI HD3SS460 (HDMI 2:1 switch).
推荐
推荐产品汇总
工程参考数据： LP38692MPX-3.3/NOPB ——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 | LP38690MPX-3.3/NOPB | LP38692MPX-3.3 | LP38692MP-3.3/NOPB | LP38692MPX-5.0/NOPB | LP38692MPX-2.5/NOPB | NCP1117DT33RKG |
|---|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | onsemi |
| Package | SOT-223-5 (NDC) | SOT-223-5 (NDC) - same | SOT-223-5 (NDC) - same | SOT-223-5 (NDC) - same | SOT-223-5 (NDC) - same | SOT-223-5 (NDC) - same | DPAK (TO-252) - DIFFERENT |
| Output Voltage | 3.3 V | 3.3 V | 3.3 V | 3.3 V | 5.0 V | 2.5 V | 3.3 V |
| Output Current | 1 A | 1 A | 1 A | 1 A | 1 A | 1 A | 1 A |
| Input Voltage Range | 2.7 V to 10 V | 2.7 V to 10 V | 2.7 V to 10 V | 2.7 V to 10 V | 2.7 V to 10 V | 2.7 V to 10 V | up to 15 V |
| Dropout Voltage (Typ @ 1 A) | 450 mV | 450 mV | 450 mV | 450 mV | 450 mV | 450 mV | ~1.2 V |
| Enable Pin | Yes (active-high) | No | Yes (active-high) | Yes (active-high) | Yes (active-high) | Yes (active-high) | No |
| Lead-Free / RoHS | Yes (NOPB) | Yes (NOPB) | No (non-NOPB) | Yes (NOPB) | Yes (NOPB) | Yes (NOPB) | Yes |
关键差异点
- Active-high enable pin for 1 µA shutdown （对比 LP38690MPX-3.3/NOPB)
- Fixed output eliminates external resistor divider （对比 Adjustable LP38692 variants (LP38692-ADJ))
- Lower dropout than older-generation 1117 LDOs （对比 NCP1117DT33RKG (onsemi))
设计说明
At 5 V input, 3.3 V output, and 1 A load, the LP38692MPX-3.3/NOPB dissipates approximately 1.7 W. The SOT-223-5 (NDC) thermal resistance (theta_JA) is ~50 °C/W on a 1-oz 1-square-inch copper pour, yielding a junction temperature rise of about 85 °C above 25 °C ambient, putting TJ near 110 °C at full load. Estimated input values: VIN=5V, VOUT=3.3V, IOUT=1A, theta_JA=50 °C/W on minimum recommended pad. For continuous full-load operation at high ambient (>70 °C), increase copper pour to 2 square inches or add a small clip-on heatsink to keep TJ below 125 °C. The thermal-overload protection will throttle the output if junction temperature exceeds safe limits, but sustained throttling indicates insufficient heatsinking.
Place input and output ceramic capacitors within 1-2 mm of the LP38692MPX-3.3/NOPB pins. Use a 1 µF X7R ceramic at the input and a 1-10 µF X7R ceramic at the output; the device is stable with low-ESR ceramic output capacitors, eliminating the need for bulk tantalum. Keep the SOT-223 tab land pattern large (at least 1 square inch of copper across multiple layers with thermal vias) for heat dissipation. Route the EN signal away from the output inductor or switching converter to avoid noise injection. Star-ground the input cap, output cap, and load ground returns to the device GND pin to minimize ground bounce.
Do not exceed the absolute maximum input voltage of 10 V; voltage transients above this rating will permanently damage the device. Ensure the EN pin is never left floating - although the LP38692 includes an internal pull-up, an unconnected EN pin can pick up noise and cause erratic regulator behavior. Do not exceed 1 A continuous output current; while foldback current limit will protect the device under short-circuit conditions, sustained operation above 1 A will trigger thermal shutdown. Verify output voltage accuracy over the full -40 °C to +125 °C range, not just at 25 °C - the ±2.5% specification at 25 °C widens at temperature extremes.
合规信息
RoHS compliant per /NOPB lead-free finish designation. REACH compliance per TI product page. Not AEC-Q100 qualified - this is a commercial/industrial grade part. Halogen-free per TI material declaration. Conflict-minerals compliant per TI supply chain disclosure.
