LM317LCPK - 100mA Adjustable Positive Regulator | Texas Instruments
料号： LM317LCPK ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $0.45 | $0.45 |
| 10 | $0.38 | $3.80 |
| 100 | $0.29 | $29.00 |
| 500 | $0.24 | $120.00 |
| 1,000 | $0.19 | $190.00 |
LM317LCPK 概述
A linear voltage regulator is a type of voltage regulator that maintains a constant output voltage by dissipating excess power as heat. The LM317L belongs to the broader family of positive adjustable linear regulators, alongside fixed-output regulators like the LM78xx series and modern low-dropout (LDO) regulators. As a linear regulator, it offers low output noise and fast transient response, but is less efficient than a switching regulator when the input-to-output differential is large.
Key features include the 100 mA output current, the wide 1.25V to 37V adjustable output, typical line regulation of 0.01%/V, and 30 uVrms output noise. Internal current limiting, safe-area compensation, and thermal overload protection are built in. The LM317LC series is characterized for a junction temperature range of 0C to +125C.
Technically, the LM317L uses a bandgap reference and an error amplifier. The output voltage follows the classic formula VOUT = 1.25V * (1 + R2/R1) + IADJ * R2, with a 1.25V reference and 50 uA adjustment pin current. Typical quiescent (adjustment pin) current is low, and the SOT-89-3 tab provides improved thermal dissipation versus SOT-23 packages.
Typical applications include on-board regulation for microcontrollers, analog sensor interfaces, low-power audio circuits, and battery-powered devices where a stable adjustable rail is required.
Design tip: maintain at least 3V input-to-output headroom, keep input and output capacitors close to the device, and solder the tab to a copper pour for heat dissipation at higher VIN-VOUT deltas.
直接替换替代料： LM317LCPK ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
快速对比工具——选择替代料号进行并排对比：
LM317LIPK
✅ 直接替换📋 参考替代料（不在目录中）
LM317KC
✅ 直接替换📋 参考替代料（不在目录中）
LM317MT
✅ 直接替换📋 参考替代料（不在目录中）
TL783
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
L200
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
LM317LCPK 最大额定值与电气特性
| 输出类型 | Adjustable |
| 输出电压范围 | 1.25 V to 37 V |
| 最大输出电流 | 100 mA |
| 输入电压范围 | 3.75 V to 35 V |
| 输出噪声 | 30 uVrms |
| Line Regulation | 0.01%/V (typical) |
| 静态电流 | 1.5 mA (typical) |
| Adjustment Pin Current | 50 uA (typical) |
| 热阻 | 52 C/W (theta_JA) |
| 工作温度 | 0C to +125C |
| 封装 | SOT-89-3 (PK) |
| 安装类型 | Surface Mount |
| RoHS 状态 | Compliant |
LM317LCPK 引脚配置
| 引脚 1 | ADJ — Adjustment pin for setting output voltage |
| 引脚 2 | OUT — Regulated output voltage |
| 引脚 3 | IN — Input supply voltage |
典型应用
LM317LCPK 适用于 6 应用s: Microcontroller Power Supply, Analog Sensor Interface, Low-Power Audio Circuits, Battery-Powered Devices, Industrial Control Systems, Test and Measurement Equipment.
Microcontroller Power Supply
The LM317LCPK provides a stable adjustable voltage rail for microcontrollers, with 100mA output sufficient for most MCU boards. Its low noise (30 uVrms) ensures reliable operation of analog peripherals. The SOT-89-3 package is compact for space-constrained designs. Place input/output capacitors close to the device to maintain stability.
推荐
Analog Sensor Interface
The LM317LCPK is ideal for powering analog sensors that require a clean, adjustable supply. Its 30 uVrms noise and 0.01%/V line regulation minimize supply-induced errors in sensor readings. The adjustable output allows precise calibration of sensor bias voltages. Use a 10uF output capacitor to improve transient response.
推荐
Low-Power Audio Circuits
The LM317LCPK provides a low-noise supply for audio preamplifiers and headphone amplifiers. Its 30 uVrms noise is well below audible levels, and the adjustable output allows optimization of the operating point. The linear regulation avoids switching noise, preserving audio fidelity. Ensure adequate heat dissipation for higher input-output differentials.
推荐
Battery-Powered Devices
The LM317LCPK is suitable for battery-powered devices where a stable voltage is needed despite battery voltage variation. Its low quiescent current (1.5 mA) extends battery life, and the adjustable output allows matching the supply to the load requirements. For maximum efficiency, consider a switching regulator if the input-output differential is large.
推荐
Industrial Control Systems
The LM317LCPK provides a reliable adjustable supply for industrial control circuits, such as PLC I/O modules and sensor transmitters. Its wide input range (up to 35V) accommodates 24V industrial buses, and the thermal overload protection ensures safe operation. The SOT-89-3 package is robust for harsh environments.
推荐
Test and Measurement Equipment
The LM317LCPK is used in test equipment to provide a stable, adjustable reference voltage for calibration and measurement circuits. Its low noise and excellent line regulation ensure accurate readings. The adjustable output allows fine-tuning of reference levels. Use precision resistors for the adjustment network to maintain accuracy.
推荐
推荐产品汇总
工程参考数据： LM317LCPK ——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 | LM317LIPK | LM317KC | LM317MT |
|---|---|---|---|---|
| Package | SOT-89-3 (PK) | SOT-89-3 (PK) - same | SOT-89-3 - same | SOT-89-3 - same |
| Brand | Texas Instruments | Texas Instruments | International Rectifier | Texas Instruments |
| Output Current | 100 mA | 100 mA | 100 mA | 100 mA |
| Output Voltage Range | 1.25V to 37V | 1.25V to 37V | 1.25V to 37V | 1.25V to 37V |
| Input Voltage Range | 3.75V to 35V | 3.75V to 35V | 3.75V to 35V | 3.75V to 35V |
| Output Noise | 30 uVrms | 30 uVrms | 30 uVrms | 30 uVrms |
| Operating Temperature | 0C to +125C | -40C to +125C | 0C to +125C | 0C to +125C |
| Quiescent Current | 1.5 mA | 1.5 mA | 1.5 mA | 1.5 mA |
关键差异点
- Wide temperature range option （对比 LM317LIPK)
- Low output noise （对比 LM317KC)
- Compact SOT-89-3 package （对比 LM317T)
设计说明
The SOT-89-3 package has a thermal resistance of 52 C/W. At VIN=12V, VOUT=5V, and 100mA load, power dissipation is 0.7W, resulting in a 36.4C temperature rise. For higher dissipation, solder the tab to a larger copper pour or use a heatsink. Ensure the junction temperature stays within 0C to +125C.
Place input and output capacitors (typically 0.1uF and 1uF) as close to the device pins as possible. The adjustment pin should have a bypass capacitor (10uF) to improve ripple rejection. Use a ground plane to minimize noise and ensure stable operation.
Do not exceed the maximum input voltage of 35V. Maintain at least 3V input-to-output headroom for proper regulation. Use 1% or better resistors for the adjustment network to maintain output voltage accuracy. Avoid long traces to the adjustment pin to prevent noise pickup.
合规信息
RoHS compliant per TI product page. Not AEC-Q100 qualified.
