MIC5239-5.0YS-TR - 5V 500mA Low-Iq LDO SOT-223 | Microchip
料号： MIC523950YSTR ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $3.28 | $3.28 |
| 10 | $2.95 | $29.50 |
| 100 | $2.52 | $252.00 |
| 500 | $2.1 | $1,050.00 |
| 1,000 | $1.78 | $1,780.00 |
MIC523950YSTR 概述
A low-dropout regulator is a type of linear voltage regulator that maintains a regulated output even when the input voltage is only marginally higher than the output. Within the power management IC hierarchy, the MIC5239 belongs to the LDO family of positive linear regulators, positioned as a high-input-voltage, low-quiescent-current solution that sits between standard linear regulators and full switching converters.
Key differentiating specifications include the 30V maximum input rating, which allows direct connection to high-voltage battery rails; the 23uA quiescent current, which minimizes standby drain in keep-alive power circuits; the 350mV dropout at 500mA, enabling efficient post-regulation after a switching converter; and uCap output architecture that is stable with low-ESR ceramic capacitors.
Architecturally, the MIC5239 uses a PNP pass element driven by a precision reference and error amplifier. The low quiescent current is achieved through a biased internal supply technique rather than a conventional resistor string, so ground-pin current stays low across the full load range. The fixed 5.0V version integrates the feedback divider internally, eliminating external resistors and reducing BOM count.
Typical applications include keep-alive and always-on power in automotive and industrial systems with high-voltage batteries, USB peripheral power where 500mA is required, post-regulation of switching converter rails for noise-sensitive analog circuitry, and battery-powered instrumentation that must sleep at microamp levels.
For design, ensure input-to-output headroom stays above the 350mV dropout specification at the actual load current, and place at least 1uF of ceramic output capacitance close to the pin for stability, per the manufacturer datasheet.
This page synthesizes distributor pricing as of 2026-10-16, drop-in same-family alternatives, and practical design notes not found in the manufacturer datasheet.
直接替换替代料： MIC523950YSTR ——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：
MIC5239-3.3YS-TR
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
MIC5239-3.0YS-TR
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
MIC5239-ADJ
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
MIC523950YSTR 最大额定值与电气特性
| 输出类型 | Fixed |
| 输出电压 | 5 V |
| 最大输出电流 | 500 mA |
| 压差电压 | 350 mV at 500 mA |
| 静态电流 | 23 uA |
| 输出数量 | 1 |
| Polarity | Positive |
| Output Capacitor Type | uCap (stable with ceramic, low-ESR) |
| 封装 | SOT-223-4 (TO-261-4 / TO-261AA) |
| 安装类型 | Surface Mount |
| 使能引脚 | Yes (per datasheet SOT-223 pinout) |
| Packaging | Tape & Reel (TR suffix) |
| Grade | Suitable for automotive applications (per distributor listing) |
MIC523950YSTR 引脚配置
| 引脚 1 | IN — Input supply voltage (up to 30 V) |
| 引脚 2 | GND — Ground |
| 引脚 3 | EN — Enable input; tie high to VIN for always-on operation |
| 引脚 4 | OUT — Regulated 5 V output (connected to large tab for heat dissipation) |
典型应用
MIC523950YSTR 适用于 6 应用s: Automotive Keep-Alive Power, USB Peripheral Power, Post-Regulation of Switching Rails, Battery-Powered Instrumentation, Industrial Control Always-On Domain, High-Voltage Battery Systems and IoT Nodes.
Automotive Keep-Alive Power
The MIC5239-5.0YS-TR fits automotive keep-alive supplies because its 30V maximum input survives high-voltage battery transients while its 23uA quiescent current prevents meaningful drain from the battery when the vehicle is parked. The regulator continuously powers ECUs, memory keep-alive domains, and wake-up logic from a 12V rail with wide headroom, per the Microchip datasheet's stated intent for high-voltage-battery systems. In this topology the device sits between the battery rail and a low-power always-on domain, feeding a fixed 5V rail with at least 1uF ceramic output capacitance. The quantified benefit is a standby drain of roughly 23uA plus load current, orders of magnitude below conventional 5mA-class regulators, protecting battery state of charge over long parking periods.
推荐
USB Peripheral Power
The Microchip datasheet explicitly cites USB as a target application because the MIC5239 delivers the 500mA USB budget with only 350mV dropout. Powered from a 6V to 30V source such as an external adapter or a post-buck intermediate rail, the MIC5239-5.0YS-TR regulates a clean fixed 5V line without switching noise, protecting USB data-integrity requirements. The uCap architecture allows a compact 1uF ceramic output capacitor rather than bulky tantalum, keeping the bill of materials small for dongles, hubs, and peripheral adapters. The SOT-223-4 tab solders to a copper pour, providing adequate thermal conduction for continuous 500mA operation. The trade-off versus a buck converter is efficiency: at 12V input the device dissipates about 3.5W at full load, so verify thermal margin or feed it from a pre-regulated 5.5V rail.
推荐
Post-Regulation of Switching Rails
Placing the MIC5239-5.0YS-TR after a buck converter combines the efficiency of switching conversion with the low noise of a linear regulator. The LDO's 350mV dropout permits regulation from a 5.5V intermediate rail, dissipating only about 250mW at 500mA load, while its 23uA quiescent current adds negligible overhead. The result is a low-ripple 5V rail suitable for RF stages, precision analog front ends, and clock circuitry that reject switching spurs poorly. The uCap stability with ceramic capacitors keeps the layout compact and avoids ESR-sensitive compensation. Designers should confirm the upstream converter's output ripple stays within the LDO's PSRR capability at the switching frequency, as detailed in the Microchip MIC5239 datasheet's application section.
推荐
Battery-Powered Instrumentation
Portable and battery-powered instruments benefit from the MIC5239-5.0YS-TR's 23uA quiescent current, which extends sleep-mode battery life substantially compared with regulators drawing milliamps of ground current. The 30V input tolerance supports multi-cell lithium and lead-acid stacks directly, while the fixed 5V output powers microcontrollers, displays, and sensor front ends. Because the device is stable with ceramic capacitors, the total solution footprint stays small for handheld enclosures. During active measurement the 500mA capability covers wireless modules and OLED displays without current starvation. Per the Microchip datasheet, the dropout of 350mV lets the instrument extract more usable capacity from a discharging battery than higher-dropout alternatives, quantifiably extending runtime near end-of-discharge.
推荐
Industrial Control Always-On Domain
In factory automation and industrial controllers, a subset of logic must remain powered while the main processing domain sleeps. The MIC5239-5.0YS-TR supplies this always-on domain from 24V industrial rails well within its 30V maximum input, delivering a fixed 5V at up to 500mA for wake-up receivers, real-time clocks, and supervision circuits. The 23uA quiescent current meets low standby-power targets demanded by modern industrial equipment efficiency standards. Its uCap ceramic-capacitor stability tolerates the electrically noisy industrial environment, and the SOT-223 tab provides robust thermal and mechanical mounting on standard FR4 boards. Designers should add input surge consideration and verify worst-case input transients against the 30V rating per the Microchip MIC5239 datasheet absolute maximum section.
推荐
High-Voltage Battery Systems and IoT Nodes
Smart IoT nodes and battery-pack electronics frequently need a small 5V logic rail tapped from a high-voltage stack. The MIC5239-5.0YS-TR connects directly to inputs up to 30V without a front-end switching stage, simplifying the power tree and eliminating inductor-generated EMI near sensitive radio circuits. With 23uA quiescent current, battery-pack fuel gauges and wireless wake-up receivers can remain powered for years on primary cells. The fixed 5V output with 500mA capability covers microcontroller, sensor, and short-range radio needs. Because the regulator is a linear device with no switching harmonics, RF sensitivity and spurious-emission concerns are minimized. Verify that the continuous input-to-output differential power dissipation stays within the SOT-223 thermal capability as calculated from the Microchip datasheet thermal data.
推荐
推荐产品汇总
工程参考数据： MIC523950YSTR ——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 | MIC5239-3.3YS-TR | MIC5239-3.0YS-TR | MIC5239-ADJ |
|---|---|---|---|---|
| Package | SOT-223-4 (TO-261AA) | SOT-223-4 - same | SOT-223-4 - same | SOT-223-4 - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Output Voltage | 5 V (fixed) | 3.3 V (fixed) | 3.0 V (fixed) | Adjustable via resistor divider |
| Output Current | 500 mA | 500 mA | 500 mA | 500 mA |
| Maximum Input Voltage | 30 V | 30 V | 30 V | 30 V |
| Quiescent Current | 23 uA | 23 uA | 23 uA | 23 uA |
| Dropout Voltage | 350 mV at 500 mA | 350 mV at 500 mA | 350 mV at 500 mA | 350 mV at 500 mA |
| External Feedback Resistors | Not required (internal divider) | Not required (internal divider) | Not required (internal divider) | Required (2 resistors) |
关键差异点
- Ultra-low quiescent current for keep-alive supplies （对比 Conventional 500mA LDOs with mA-class ground current)
- High input voltage tolerance in a small package （对比 MIC5239-3.3YS-TR)
- Fixed output eliminates BOM versus adjustable variant （对比 MIC5239-ADJ)
设计说明
Estimated: at 12V input, 5V output, and 500mA load, the MIC5239-5.0YS-TR dissipates approximately 3.5W ((12V - 5V) x 0.5A). The SOT-223 tab must be soldered to a substantial copper pour; consult the Microchip MIC5239 datasheet thermal resistance data and verify junction temperature against the maximum rating. For large VIN-VOUT differentials, either reduce load current, add a pre-regulating buck stage, or select a package with better thermal performance.
Place a minimum 1uF ceramic capacitor on the output as close to the OUT pin as possible; the MIC5239 is a uCap LDO and is stable with low-ESR ceramic output capacitance per the Microchip datasheet. Add an input capacitor when the supply source impedance is high or input leads are long. The OUT tab (pin 4) doubles as the thermal path, so maximize copper area under the tab on the top layer with thermal vias to inner planes.
Do not exceed the 30V maximum operating input voltage; automotive load-dump transients can exceed this without external clamping. If always-on operation is required, tie the EN pin to VIN rather than leaving it floating. Estimated: ceramic capacitors can lose 20-50% of rated capacitance under DC bias (verify effective capacitance at 5V bias) - undersized effective output capacitance can compromise stability at high load currents.
合规信息
Distributor listing describes the part as suitable for automotive applications; formal AEC-Q100 qualification for this exact suffix is not confirmed in the verified data. RoHS/REACH status not stated in provided data.
