LT3090IMSE - -36V, 600mA Negative LDO Regulator | Analog Devices
料号： LT3090IMSE ✓ 量产中LT3090IMSE 概述
A Low-Dropout (LDO) linear regulator is a type of voltage regulator that maintains a stable output voltage with a very small input-to-output voltage differential, making it essential in power management IC hierarchies. LDOs belong to the broader linear regulator family, which in turn sits inside voltage regulators and the overall power management semiconductor category. Unlike switching regulators, LDOs introduce no switching noise but dissipate more power when VIN-VOUT is large, so they are chosen specifically where noise floor, ripple rejection, and simplicity outweigh efficiency.
The LT3090 is engineered around a precision current reference and a high-performance rail-to-rail operational amplifier. This two-stage architecture provides excellent load regulation (Kelvin-sensed at the OUT pin), programmable current limit, and easy paralleling of multiple devices to scale output current or spread heat. The 12-pin MSOP-EP package with exposed pad reduces junction-to-ambient thermal resistance, supporting higher continuous current on a small PCB footprint.
Typical applications include negative-supply rails for op-amps and ADCs, industrial -24V bus interfaces, low-noise post-regulation after switching converters, test-and-measurement instrumentation, and any system that needs a clean negative bias. The wide -36V input range also covers telecom -48V systems after a front-end regulator.
When designing with this part, place input and output capacitors close to the IC pins, Kelvin-connect the ground side of the SET resistor to the load, and verify that PCB copper area on the exposed pad can absorb worst-case dissipation (estimated Pdiss = (|VIN| - |VOUT|) × IOUT). For demanding thermal conditions, parallel multiple LT3090s on the same footprint to spread heat.
直接替换替代料： LT3090IMSE ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
LT3090EMSE#PBF
✅ 直接替换📋 参考替代料（不在目录中）
LT3090HMSE#PBF
✅ 直接替换📋 参考替代料（不在目录中）
LT3090IMSE#TRPBF
✅ 直接替换📋 参考替代料（不在目录中）
LT3090EMSE#TRPBF
✅ 直接替换📋 参考替代料（不在目录中）
LT3090HMSE#TRPBF
✅ 直接替换📋 参考替代料（不在目录中）
LT3090IMSE 最大额定值与电气特性
| 拓扑 | Negative Low-Dropout (LDO) Linear Regulator |
| 输入电压范围 | -1.5 V to -36 V |
| 输出电压范围 | 0 V to -32 V (adjustable) |
| 最大输出电流 | 600 mA |
| Reference Current | 200 µA (precision current reference) |
| 限流 | Programmable via external resistor |
| 输出类型 | Adjustable (single resistor) |
| Parallel Operation | Yes (for higher current or heat spreading) |
| Load Regulation | Kelvin-sensed at OUT pin |
| 工作温度范围 | -40 °C to +125 °C (I grade) |
| 封装 | 12-pin MSOP-EP (MSE) with exposed thermal pad |
| 安装类型 | Surface Mount |
| RoHS 状态 | Compliant (PBF suffix indicates lead-free) |
| Order Suffix | #PBF = lead-free; #TRPBF = tape & reel, lead-free |
LT3090IMSE 引脚配置
| 引脚 1 | OUT — Regulated output voltage (Kelvin-sensed) |
| 引脚 2 | IN — Negative input supply |
| 引脚 3 | IN — Negative input supply |
| 引脚 4 | SHDN — Shutdown / enable input |
| 引脚 5 | ILIM — Current-limit programming pin |
| 引脚 6 | SET — Output voltage setting (200 µA reference) |
| 引脚 7 | GND — Ground (Kelvin return for SET resistor) |
| 引脚 8 | INTVCC — Internal bypass / sub-regulator output |
| 引脚 9 | NC — Not connected (per datasheet) |
| 引脚 10 | NC — Not connected (per datasheet) |
| 引脚 11 | NC — Not connected (per datasheet) |
| 引脚 12 | NC — Not connected (per datasheet) |
| 引脚 EP | GND — Exposed thermal pad - tie to ground plane for heat sinking |
典型应用
LT3090IMSE 适用于 6 应用s: Negative Rail for Op-Amps and ADCs, Industrial -24V Bus Interface, Telecom -48V Post-Regulator, Low-Noise Bias for RF and Mixed-Signal, Test-and-Measurement Instrumentation, Automotive Sensor and ECU Subsystems.
Negative Rail for Op-Amps and ADCs
The LT3090IMSE is well suited to negative-rail generation for precision op-amps and ADCs that require a low-noise -5 V or -12 V supply. Its 200 µA precision current reference plus rail-to-rail buffer topology provides clean DC with no switching noise, while the 600 mA continuous output can feed multiple amplifier stages. Place the part near the load with Kelvin sensing at OUT, and use 10 µF ceramic input/output capacitors to maintain stability across load steps.
推荐
Industrial -24V Bus Interface
Industrial automation backplanes typically carry a -24 V bus that must be regulated down to -12 V or -5 V for downstream analog sections. The LT3090IMSE accepts up to -36 V at IN, tolerating transients on the -24 V bus without damage, and delivers up to 600 mA continuously. Its exposed-pad MSOP-EP package handles worst-case dissipation (estimated up to ~6 W at 100 mA on a -24V-to-12V conversion) on a modest copper pour, suuing compact PLC and sensor-front-end designs.
推荐
Telecom -48V Post-Regulator
After a front-end converter drops telecom -48 V to a -36 V or lower intermediate rail, the LT3090IMSE acts as a low-noise post-regulator for line-card analog circuits. Its -36 V input rating directly accepts that intermediate bus, while its 600 mA output covers several codec/filter channels. Paralleling two LT3090IMSEs spreads heat and increases current to ~1.2 A for higher-power SERDES blocks, with no change in PCB footprint.
推荐
Low-Noise Bias for RF and Mixed-Signal
RF transceivers, PLLs, and high-speed ADCs are notoriously sensitive to power-rail noise. The LT3090IMSE's current-reference architecture avoids the switching noise of a buck and adds only the regulator's own thermal noise, making it ideal for biasing VCOs and mixer stages. Drive the LT3090IMSE from a -12 V or -15 V analog rail and program output with a single resistor for a clean -5 V or -3.3 V bias.
推荐
Test-and-Measurement Instrumentation
Bench power supplies and modular instruments rely on low-noise, predictable negative rails to test DUTs accurately. The LT3090IMSE's Kelvin-sensed OUT pin and programmable current limit let designers add precision current-limit protection with one resistor, while the adjustable 0 V to -32 V output covers the -1.2 V to -30 V range demanded by op-amp, ADC, and sensor characterization. Use multiple LT3090IMSEs in parallel for high-current instrument channels.
推荐
Automotive Sensor and ECU Subsystems
Automotive ECUs often need a clean negative bias for Hall-effect sensors, op-amps, and certain sensor front-ends that operate from a -12 V truck/bus rail. The LT3090IMSE handles cold-crank transients down to -36 V, and its MSOP-EP footprint suits compact ECU boards. For AEC-Q100-qualified designs, choose a different ADI part since the LT3090IMSE itself is not AEC-Q100 qualified.
推荐
推荐产品汇总
工程参考数据： LT3090IMSE ——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 | LT3090EMSE#PBF | LT3090HMSE#PBF | LT3090IMSE#TRPBF | LT3090EMSE#TRPBF | LT3090HMSE#TRPBF |
|---|---|---|---|---|---|---|
| Package | 12-pin MSOP-EP (MSE) | 12-pin MSOP-EP (MSE) - same | 12-pin MSOP-EP (MSE) - same | 12-pin MSOP-EP (MSE) - same | 12-pin MSOP-EP (MSE) - same | 12-pin MSOP-EP (MSE) - same |
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Maximum Output Current | 600 mA | 600 mA | 600 mA | 600 mA | 600 mA | 600 mA |
| Input Voltage Range | -1.5 V to -36 V | -1.5 V to -36 V | -1.5 V to -36 V | -1.5 V to -36 V | -1.5 V to -36 V | -1.5 V to -36 V |
| Output Voltage Range | 0 V to -32 V | 0 V to -32 V | 0 V to -32 V | 0 V to -32 V | 0 V to -32 V | 0 V to -32 V |
| Operating Temperature Range | -40 °C to +125 °C (I grade) | -40 °C to +85 °C (E grade) | -40 °C to +150 °C (H grade) | -40 °C to +125 °C (I grade, T&R) | -40 °C to +85 °C (E grade, T&R) | -40 °C to +150 °C (H grade, T&R) |
| Programmable Current Limit | Yes | Yes | Yes | Yes | Yes | Yes |
| Parallelable | Yes | Yes | Yes | Yes | Yes | Yes |
| 1ku List Price (USD, as of 2026-10-08) | 3.29 | 3.29 | 3.29 | 3.29 | 3.29 | 3.29 |
关键差异点
- Wide -36V input with 600 mA in MSOP-EP （对比 LT3092 (legacy 200 mA / ±20 V negative LDO))
- Programmable current limit via single resistor （对比 Fixed-limit negative LDOs in same MSOP-EP)
- Easy paralleling for higher current or heat spreading （对比 Single-supply negative LDOs without parallel support)
设计说明
At VIN = -24 V, VOUT = -12 V and 600 mA load, estimated dissipation is (24-12) × 0.6 = 7.2 W. The 12-pin MSOP-EP package requires a substantial exposed-pad copper pour (at least 1 square inch of 2 oz copper) to keep the junction temperature below the rated maximum. For continuous 600 mA at large VIN-VOUT differentials, consider paralleling two LT3090s on the same footprint to halve per-device dissipation.
Kelvin-connect the ground side of the SET resistor directly to the load's negative terminal, not to the local IC ground. This removes the voltage drop across the PCB ground trace from the regulation loop and preserves the rated load regulation per the LT3090 datasheet's Figure 8 reference layout. Place input/output ceramic capacitors (10 µF minimum) as close as possible to the IN and OUT pins.
Do not omit the exposed-pad solder connection - it is the primary thermal path. Do not exceed -36 V at IN; transients beyond this can damage the device. Use the ILIM resistor value recommended in the datasheet's table; too large disables current-limit protection, while too small prematurely limits the 600 mA output. The #PBF and #TRPBF suffixes indicate lead-free (RoHS) packaging - confirm the suffix matches your assembly process.
Keep the SET and ILIM traces away from switching-node traces if the upstream converter is on the same board - capacitive coupling can modulate the output. When paralleling multiple LT3090s, add a small ballast resistor (typically 0.05-0.1 Ω) in series with each OUT pin to balance current sharing. Star-ground the SET resistors at the load to prevent ground loops.
合规信息
RoHS compliant per the #PBF/#TRPBF order suffix. Not AEC-Q100 qualified - automotive designs should use an AEC-Q100-grade part instead. Conflict-minerals statement available on Analog Devices' corporate compliance page.
