Microchip Technology MCP1812AT-028/LB

Overview

MCP1812AT-028/LB from Microchip Technology is a 300 mA ultra-low-quiescent-current LDO regulator with fixed 2.8 V output, 250 nA typical IQ, and shutdown capability (5 nA typical ISHDN). It operates from 1.8V to 5.5V input and is stable with a 2.2 µF ceramic output capacitor. Designed for energy harvesting and long-life battery-powered systems such as wearable medical sensors and smart cards.

For engineers reviewing the MCP1812AT-028/LB datasheet, MCP1812AT-028/LB pinout, MCP1812AT-028/LB application, or MCP1812AT-028/LB equivalent, this page delivers verified electrical specs, package mapping, functional role in low-power sleep/wake architectures, and validated alternative options for ultra-low-I_Q LDO selection.

Technical Context

The MCP1812AT-028/LB belongs to the MCP1812X family - the 300 mA variant of Microchip's ultra-low-I_Q LDO series. It features an internal discharge transistor (RDCH = 100 Ω) active during shutdown (SHDN = GND), enabling rapid VOUT discharge to prevent residual voltage hold-up in power-gated subsystems.

Its architecture supports operation down to 1.8 V input while maintaining regulation at 2.8 V output up to 300 mA load, with dropout voltage ≤600 mV at full load. Thermal performance is optimized for the 4-lead 1×1 mm UDFN package (θ_JA = 91.05 °C/W on JEDEC 4-layer board).

Key Specifications

Pinout & Package

Package: 4-Lead 1 × 1 mm UDFN with exposed thermal pad (EP). Optimized for space-constrained PCBs and thermal performance in thin-profile wearables.

Key Features

Applications

Equivalent & Alternatives

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

Compared with XC6210B282MR-G and RP114K281D-TR-F, the MCP1812AT-028/LB uniquely combines 300 mA drive, 5 nA shutdown, and integrated discharge in a 1×1 mm UDFN - enabling smallest PCB area and most robust power sequencing in space- and energy-constrained designs.

Availability

MCP1812AT-028/LB is available at Aetrix Electronics and suitable for energy harvesting nodes, wearable medical sensors, and smart card interfaces requiring stable component supply with guaranteed long-term manufacturability and traceable sourcing.

Supply support for MCP1812AT-028/LB 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.

The MCP1811/12 family was designed specifically for ultra-low-power, long-life battery and energy-harvesting applications - prioritizing nanoscale quiescent current, ceramic-capacitor stability, and integrated power-control features like output discharge.

FAQ

What is the maximum continuous output current of the MCP1812AT-028/LB?

The MCP1812AT-028/LB delivers up to 300 mA of continuous output current while maintaining regulation at 2.8 V output. This rating is confirmed in Table 1 and AC/DC Characteristics (DS20006088C, page 4), and applies across the full operating junction temperature range of –40°C to +85°C.

Does the MCP1812AT-028/LB include output discharge functionality?

Yes, the MCP1812AT-028/LB includes an integrated discharge transistor (RDCH = 100 Ω) that actively pulls VOUT to GND when SHDN is driven low. This feature is explicitly assigned to the "A" suffix variants (MCP1812A), and MCP1812AT-028/LB follows the A-series designation per Microchip's part numbering convention and family documentation.

What output capacitor value is required for stability with the MCP1812AT-028/LB?

A minimum 2.2 µF X7R ceramic capacitor is required at the VOUT pin for stability. This value is specified in the Features section and Electrical Characteristics table (DS20006088C, pages 1 and 4) and applies specifically to the MCP1812X series, including the MCP1812AT-028/LB.

What is the shutdown supply current for the MCP1812AT-028/LB?

The MCP1812AT-028/LB exhibits 5 nA typical shutdown supply current (ISHDN), consistent with the MCP1812B variant per Table 1. Although the "T" suffix denotes tape-and-reel packaging and "/LB" indicates the 4-lead UDFN package, the device shares the B-series shutdown specification due to its fabrication and test binning as a low-leakage variant.

Which package type does the MCP1812AT-028/LB use?

The MCP1812AT-028/LB uses the 4-Lead 1 × 1 mm UDFN package with exposed thermal pad (EP), as indicated by the "/LB" suffix in the part number and confirmed in Package Types (DS20006088C, page 2). This package provides superior thermal performance (θ_JA = 91.05 °C/W) versus SOT-23 or SC70 alternatives.