Microchip Technology MIC5265-2.8YD5-TR

Overview

MIC5265-2.8YD5 from Micrel is a 150mA low-dropout linear regulator delivering a fixed 2.8V output, designed for noise-sensitive RF and portable digital systems. It operates from 2.7V to 5.5V input, achieves 210mV dropout at full load, features 57µV_rms output noise and 60dB PSRR at 1kHz, and includes an active-high enable pin and integrated active shutdown circuitry for zero-off current in battery-powered handheld devices.

For engineers reviewing the MIC5265-2.8YD5 datasheet, MIC5265-2.8YD5 pinout, MIC5265-2.8YD5 application, or MIC5265-2.8YD5 equivalent, key selection criteria include its Thin SOT-23-5 package footprint, ceramic-capacitor stability, fast transient response, thermal shutdown behavior, and compatibility with single-cell Li-ion or fixed 3.3V/5V rails.

Technical Context

The MIC5265-2.8YD5 integrates a CMOS-based error amplifier, reference voltage generator with bypass pin (BYP), and active-shutdown N-channel MOSFET for rapid output discharge. Its architecture supports stable regulation down to zero load while maintaining low noise via external 0.01µF BYP capacitor filtering of the internal reference.

It employs under-voltage lockout and thermal shutdown (150°C trip, 10°C hysteresis) to ensure safe operation across –40°C to +125°C junction temperature range. The device draws only 75µA quiescent current and exhibits fast turn-on time (40–150µs) with minimal sensitivity to input/output capacitor ESR.

Key Specifications

Pinout & Package

Package: Pb-free Thin SOT-23-5 (M5/D5), 2.9mm × 1.6mm × 1.1mm body, 1.27mm pitch, 235°C/W θ_JA.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LDO regulator applications.

Compared with MCP1700-2802E/TO and XC6206P282MR-G, the MIC5265-2.8YD5 uniquely balances RF-grade noise performance, active discharge, and enable control in the same Thin SOT-23-5 footprint-making it optimal for portable wireless endpoints where supply integrity and power sequencing matter.

Availability

MIC5265-2.8YD5 is available at Aetrix Electronics and suitable for cellular telephones, GPS receivers, PDAs, and Bluetooth-enabled wearables requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for MIC5265-2.8YD5 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Micrel Inc. was a U.S.-based semiconductor company specializing in analog, power management, and timing solutions before its acquisition by Microchip Technology in 2015. It emphasized high-performance, small-footprint regulators for portable electronics.

The MIC5265 product line was engineered specifically for cost-sensitive, space-constrained RF and digital portable systems-prioritizing low noise, fast transient response, and ceramic-capacitor compatibility without sacrificing thermal robustness or enable functionality.

FAQ

What is the maximum input voltage for MIC5265-2.8YD5?

The absolute maximum input voltage for MIC5265-2.8YD5 is +7V, but the recommended operating range is +2.7V to +5.5V. Exceeding 5.5V risks violating the device's safe operating area, especially under load, and may trigger thermal shutdown or degrade long-term reliability. For single-cell Li-ion applications, the 2.7V–5.5V range ensures compatibility across full charge (4.2V) to end-of-discharge (~2.8V) conditions while maintaining regulation.

Does MIC5265-2.8YD5 require an external bypass capacitor?

Yes, MIC5265-2.8YD5 includes a dedicated BYP pin to connect an external capacitor (0.01µF–1.0µF) to ground, which reduces output voltage noise and improves PSRR. While the regulator functions without it, omitting the BYP capacitor increases output noise from 57µV_rms to ~120µV_rms and degrades PSRR by up to 15dB at 1kHz-making it unsuitable for RF or precision analog applications. A 0.01µF NP0/C0G capacitor is recommended for optimal noise suppression.

Can MIC5265-2.8YD5 operate without any load connected?

Yes, MIC5265-2.8YD5 remains stable and maintains regulation at zero load-a feature critical for applications like SRAM keep-alive, RTC backup, or sensor biasing during system sleep. Unlike many LDOs that require minimum load current for stability, this device uses internal compensation optimized for no-load operation, eliminating the need for bleed resistors and reducing standby power loss.

What is the purpose of the active shutdown function in MIC5265-2.8YD5?

The active shutdown function in MIC5265-2.8YD5 uses an integrated N-channel MOSFET to actively discharge the output capacitor when the EN pin is pulled low. This ensures the regulated 2.8V rail collapses rapidly and predictably-preventing unintended operation of downstream logic, avoiding latch-up in mixed-signal ICs, and enabling clean power sequencing in multi-rail systems. Without it, residual charge on the output cap could cause erratic behavior during reset or wake-up transitions.

Is MIC5265-2.8YD5 compatible with ceramic output capacitors?

Yes, MIC5265-2.8YD5 is fully compatible with ceramic output capacitors-specifically requiring ≥1µF X7R or X5R dielectric types with ESR ≤300mΩ. It is optimized for stability with low-ESR ceramics and does not require series resistance or tantalum alternatives. Using Y5V or Z5U dielectrics is discouraged due to large capacitance drift over temperature, which may compromise regulation margin at extremes.