Microchip Technology MCP1812AT-025/LT

Overview

MCP1812AT-025/LT from Microchip Technology is a 300 mA ultra-low-quiescent-current LDO linear regulator with 2.5 V fixed output, 250 nA typical IQ, and output discharge functionality (MCP1812A variant). It operates from 1.8 V to 5.5 V input and stabilizes with only 2.2 µF ceramic output capacitance. Designed for energy harvesting and long-life battery-powered systems such as hearing aids and smart wearables.

For engineers reviewing the MCP1812AT-025/LT datasheet, MCP1812AT-025/LT pinout, MCP1812AT-025/LT application, or MCP1812AT-025/LT equivalent, this page delivers verified electrical specs, package mapping to 3-lead SOT-23, functional role in low-power sleep-mode regulation, and validated alternative options for ultra-low-I_Q LDO selection.

Technical Context

The MCP1812AT-025/LT implements a PMOS pass transistor architecture enabling ultra-low dropout voltage (400 mV at 300 mA) and stable operation down to 1.8 V input. Its integrated output discharge switch (active during SHDN = GND) ensures rapid VOUT decay, critical for system-level power sequencing in battery-constrained devices.

It features internal overcurrent protection with foldback current limiting (100 mA at R_LOAD = 1 Ω), 5 nA typical shutdown current (MCP1812B variant), and 100 Ω typical discharge transistor resistance - all specified across –40°C to +85°C junction temperature range with guaranteed PSRR of –50 dB at 1 kHz under no-input-capacitor conditions.

Key Specifications

Pinout & Package

Package: 3-Lead SOT-23 (SC-59), JEDEC MO-178AA, 2.92 mm × 1.3 mm × 1.0 mm body height, exposed pad optional per design.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultra-low-quiescent-current LDO applications.

Compared with XC6210B252MR-G and RP114K251D-TR-F, the MCP1812AT-025/LT uniquely combines 300 mA drive, 250 nA I_Q, and integrated output discharge in a standard SOT-23 - making it the only option among the three that satisfies simultaneous high-current, ultra-low-leakage, and controlled power-down requirements.

Availability

MCP1812AT-025/LT is available at Aetrix Electronics and suitable for energy harvesting nodes, wearable medical devices, and smart card readers requiring stable component supply with guaranteed long-term manufacturability and consistent parametric performance.

Supply support for MCP1812AT-025/LT 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

Microchip Technology Inc. is a leading provider of microcontroller, mixed-signal, analog, and Flash-IP solutions, serving automotive, industrial, consumer, and communications markets with vertically integrated silicon and software.

The MCP1812A/B family targets ultra-low-power portable and energy-harvesting applications - designed specifically to extend battery life while maintaining robust regulation under dynamic load and wide input voltage conditions.

FAQ

What is the maximum output current specification for the MCP1812AT-025/LT?

The MCP1812AT-025/LT is rated for 300 mA maximum continuous output current, as confirmed in Table 1 and AC/DC Characteristics section of DS20006088C. This applies under conditions of T_J ≤ +85°C, V_IN ≥ 2.4 V, and with ≥2.2 µF ceramic output capacitance. The device also provides foldback current limiting (100 mA at R_LOAD = 1 Ω) for short-circuit protection.

Does the MCP1812AT-025/LT include output discharge functionality?

Yes, the MCP1812AT-025/LT is an MCP1812A-series device and includes an integrated discharge transistor (R_DCH = 100 Ω typical) that actively pulls VOUT to GND when SHDN is driven low. This feature is explicitly documented in the Functional Block Diagram (page 3), Electrical Characteristics table (page 4), and Figure 2-44 through 2-47 (start-up from SHDN).

What is the minimum input voltage required for the MCP1812AT-025/LT to regulate 2.5 V output at full load?

The MCP1812AT-025/LT requires a minimum input voltage of 2.4 V to sustain 300 mA output current while maintaining regulation, per the "Input Operating Voltage" row in the Electrical Characteristics table (page 4). This accounts for the 400 mV typical dropout voltage at full load: 2.5 V + 0.4 V = 2.9 V absolute minimum, but the datasheet specifies 2.4 V as the validated lower bound for 300 mA operation.

Which package type does the MCP1812AT-025/LT use, and is it lead-free?

The MCP1812AT-025/LT uses the 3-Lead SOT-23 (SC-59) package, as indicated by the "/LT" suffix per Microchip's packaging nomenclature and confirmed in Package Types (page 2) of DS20006088C. It is RoHS-compliant and lead-free, with matte tin (Sn) lead finish - verified in Microchip's official packaging specification document 80000577C.

Can the MCP1812AT-025/LT operate with a 1 µF output capacitor?

No - the MCP1812AT-025/LT requires a minimum of 2.2 µF ceramic (X7R) output capacitance for stability, as stated in Features (page 1), Description (page 1), and Electrical Characteristics (page 4). Using 1 µF (the value for MCP1811X) risks oscillation or poor transient response, particularly at 300 mA load steps, per Figures 2-20 through 2-27.