MIC5219-3.3YM5 - 500mA 3.3V LDO Regulator | Microchip SOT-23-5
MPN: MIC5219-3.3YM5 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.84 | $0.84 |
| 10 | $0.71 | $7.10 |
| 100 | $0.58 | $58.00 |
| 500 | $0.47 | $235.00 |
| 1,000 | $0.39 | $390.00 |
| 3,000 | $0.34 | $1,020.00 |
MIC5219-3.3YM5 Overview
An LDO (Low-Dropout) linear regulator is a type of voltage regulator that maintains a stable output voltage even when the input voltage is very close to the output voltage, with dropout voltages much lower than classic 7805-style regulators. LDOs sit within the power management IC hierarchy and trade efficiency for noise: unlike switching regulators, an LDO adds no switching ripple, which is critical for analog and RF subsystems. The MIC5219 family is engineered specifically for battery-powered portable systems where extended runtime, low quiescent current, and low dropout at high peak current are mandatory.
Key features include a TTL/CMOS-compatible shutdown/enable input that drops quiescent current nearly to zero when disabled, current limiting, overtemperature shutdown, reversed-battery protection, and an ultra-low-noise option across the family. Output accuracy is better than 1% across line, load, and temperature. Ground current is minimized to prolong battery life, and the small SOT-23-5 footprint enables compact PCB designs. The YM5 industrial temperature grade supports -40 °C to +125 °C operation.
Typical applications include USB peripherals and dongles, portable instrumentation, handheld terminals, wireless sensor nodes, post-regulation after switching converters, and any 3.3 V microcontroller or sensor bias rail where low noise and long battery life are priorities. The MIC5219-3.3YM5 also works well as a clean local rail for low-power MCUs such as PIC microcontrollers.
When designing with this part, place the input and output bypass capacitors immediately adjacent to the IC with short, wide traces, and respect the absolute maximum input voltage. The shutdown pin can be driven from a GPIO for sequenced power-up in multi-rail systems.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for MIC5219-3.3YM5 — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MIC5219-3.3YM5-TR
✅ Drop-In📋 Reference alternative (not in catalog)
MIC5219-3.3YML-TR
✅ Drop-In📋 Reference alternative (not in catalog)
MIC5233-3.3YM5-TR
✅ Drop-In📋 Reference alternative (not in catalog)
MIC5219-3.0YM5-TR
✅ Drop-In📋 Reference alternative (not in catalog)
MIC5219-3.6YM5-TR
✅ Drop-In📋 Reference alternative (not in catalog)
MIC5219-2.5YM5-TR
✅ Drop-In📋 Reference alternative (not in catalog)
MIC5219-3.3YM5 Maximum Ratings & Electrical Characteristics
| Output Type | Fixed |
| Output Voltage | 3.3 V |
| Output Voltage Accuracy | ±1% (better than 1%) |
| Peak Output Current | 500 mA |
| Dropout Voltage (full load) | < 500 mV at 500 mA |
| Dropout Voltage (light load) | 10 mV typical |
| Shutdown Current | Drops nearly to zero |
| Enable Input | CMOS/TTL compatible |
| Operating Temperature | -40 °C to +125 °C (YM5 industrial grade) |
| Package | SOT-23-5 |
| Pin Count | 5 |
| Mounting Type | Surface Mount |
| Reverse-Battery Protection | Yes |
| Current Limiting | Yes |
| Overtemperature Shutdown | Yes |
| RoHS Status | Compliant (per distributor listings) |
MIC5219-3.3YM5 Pin Configuration
| Pin 1 | VIN — Unregulated input supply (reverse-battery protected) |
| Pin 2 | GND — Common ground / thermal pad connection |
| Pin 3 | EN — Enable input (CMOS/TTL compatible, drive high to enable) |
| Pin 4 | BYP — Reference bypass / noise reduction pin (connect capacitor to GND for ultra-low-noise operation) |
| Pin 5 | VOUT — Regulated 3.3 V output |
Typical Applications
MIC5219-3.3YM5 is suitable for 6 applications: USB Peripheral 3.3 V Rail, Portable Handheld Instrumentation, Wireless Sensor Node Power, Post-Regulation After Switching Converters, MCU and Sensor Bias Rail, Automotive Body Electronics (Non-Safety).
USB Peripheral 3.3 V Rail
The MIC5219-3.3YM5 powers the 3.3 V logic rail in USB peripherals such as dongles, HID devices, and bus-powered adapters. With 500 mA peak output, it handles in-rush on plug-in events while staying within USB suspend current limits when driven to shutdown via the EN pin. The 10 mV dropout at light loads preserves the 5 V VBUS headroom budget, and reverse-battery protection on the input shields the peripheral from mis-wired supplies during field service.
Recommended
Portable Handheld Instrumentation
Battery-powered test instruments, barcode scanners, and handheld terminals use the MIC5219-3.3YM5 to deliver a clean, fixed 3.3 V rail to microcontrollers, sensors, and BLE radios. The part's sub-1% output voltage accuracy ensures ADC reference precision, while its near-zero shutdown current extends standby runtime. Its SOT-23-5 footprint occupies less than 9 mm² of PCB area, leaving room for compact handheld layouts where every square millimeter matters.
Recommended
Wireless Sensor Node Power
IoT sensor nodes running sub-GHz radios, BLE, or LoRa on coin-cell or Li-Po batteries benefit from the MIC5219-3.3YM5's ultra-low dropout and CMOS-compatible enable. With 10 mV typical dropout at light load, the regulator continues to deliver 3.3 V well below the battery's nominal voltage, harvesting the last usable charge. The near-zero shutdown current is critical for duty-cycled sensor nodes that spend 99% of their time in sleep mode.
Recommended
Post-Regulation After Switching Converters
When a switching DC-DC converter provides the bulk supply but introduces unacceptable ripple on noise-sensitive analog rails, the MIC5219-3.3YM5 serves as a low-noise post-regulator. Its linear topology adds no switching noise of its own, and its high PSRR attenuates residual ripple from upstream converters. This hybrid architecture is widely used in mixed-signal boards where the same 3.3 V node feeds both digital and analog/MCU loads.
Recommended
MCU and Sensor Bias Rail
The MIC5219-3.3YM5 is the canonical bias supply for 3.3 V microcontrollers, MEMS sensors, and IMUs that demand sub-1% supply tolerance for accurate measurements. Its SOT-23-5 footprint is widely accepted as the smallest mainstream LDO footprint, and its enable pin allows GPIO-controlled sequenced power-up for MCUs that require rail sequencing at boot. The 500 mA peak rating supports even power-hungry radios during transmit bursts.
Recommended
Automotive Body Electronics (Non-Safety)
For non-safety automotive body electronics such as interior lighting controllers, HVAC human-machine interfaces, and seat comfort modules, the MIC5219-3.3YM5 delivers a regulated 3.3 V rail directly from the 12 V battery. The YM5 industrial temperature grade (-40 °C to +125 °C) covers automotive cabin environments. Reverse-battery protection on the input is valuable during jump-start events. For safety-critical functions, an AEC-Q100 part is required instead.
Recommended
Recommended Products Summary
Engineering reference data for MIC5219-3.3YM5 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MIC5219-3.3YM5-TR | MIC5219-3.3YML-TR | MIC5233-3.3YM5-TR | MIC5219-3.0YM5-TR | MIC5219-3.6YM5-TR | MIC5219-2.5YM5-TR |
|---|---|---|---|---|---|---|---|
| Package | SOT-23-5 | SOT-23-5 - same | SOT-23-5 - same | SOT-23-5 - same | SOT-23-5 - same | SOT-23-5 - same | SOT-23-5 - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Output Voltage | 3.3 V | 3.3 V | 3.3 V | 3.3 V | 3.0 V | 3.6 V | 2.5 V |
| Peak Output Current | 500 mA | 500 mA | 500 mA | 100 mA | 500 mA | 500 mA | 500 mA |
| Output Accuracy | ±1% | ±1% | ±1% | ±2% typical | ±1% | ±1% | ±1% |
| Enable Pin | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
| Reverse-Battery Protection | Yes | Yes | Yes | Yes | Yes | Yes | Yes |
| 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 | -40 °C to +125 °C | -40 °C to +125 °C |
Key Differentiators
- Higher peak output current than MIC5233 family in same package (vs MIC5233-3.3YM5-TR)
- Industrial-grade temperature range with same die as automotive-marked parts (vs MIC5219-3.3YML-TR)
- Exact 3.3 V output vs. 3.0 V and 3.6 V siblings (vs MIC5219-3.0YM5-TR / MIC5219-3.6YM5-TR)
Design Notes
Place the input and output bypass capacitors immediately adjacent to the IC with the shortest possible trace lengths to minimize parasitic inductance. Use a 1 µF or larger low-ESR ceramic on the input and a 1 µF or larger low-ESR ceramic on the output. For the SOT-23-5 footprint, GND pin 2 is the primary thermal path - connect it to a copper pour on the top layer and stitch to the bottom layer with multiple vias directly under the package to maximize heat dissipation.
Estimated: At VIN = 5 V, VOUT = 3.3 V, and IOUT = 500 mA, the regulator dissipates approximately (5 - 3.3) × 0.5 = 0.85 W. With the SOT-23-5 θJA of approximately 256 °C/W on a minimal copper footprint, the junction temperature rise is ~218 °C, which exceeds the 150 °C shutdown limit. To stay within thermal limits at sustained 500 mA loads, increase the PCB copper ground area connected to pin 2 to at least 1 square inch, or drop VIN closer to VOUT to reduce dissipation.
Counterfeit MIC5219 low-noise regulators have been widely reported on unauthorized marketplaces (AliExpress, eBay) that meet basic regulator function but fail the low-noise specification. Source only from authorized distributors (DigiKey, Mouser, LCSC, Microchip Direct) or verified franchised stockists. Confirm the YM5 top marking under magnification. Also, do not leave the BYP pin floating if low-noise operation is required - connect a 10 nF to 100 nF capacitor from BYP to GND to activate the ultra-low-noise mode described in the datasheet.
Drive the EN pin from a microcontroller GPIO to implement sequenced power-up or to drop quiescent current to near-zero during sleep states. Tie EN to VIN through a 100 kΩ resistor if shutdown is not used. The EN input is CMOS/TTL compatible with a logic threshold around 1.5 V, making it directly driveable from 3.3 V or 5 V logic rails without level shifting.
Compliance Information
RoHS compliance confirmed by distributor listings (DigiKey, Mouser, LCSC). Reach, halogen-free, and conflict-minerals status not explicitly stated in the verified web data; AEC-Q100 not qualified - not suitable for automotive safety-critical applications.
