Microchip Technology MCP1811BT-020/LB

Overview

MCP1811BT-020/LB from Microchip Technology is an ultra-low quiescent current (250 nA typical) 150 mA low-dropout linear regulator with fixed 2.0 V output, designed for energy-constrained battery-powered systems. It operates from 1.8 V to 5.5 V input, supports ceramic output capacitors as small as 1.0 µF, and features shutdown mode with only 5 nA typical supply current - ideal for wearable electronics and medical devices requiring multi-year battery life.

For engineers reviewing the MCP1811BT-020/LB datasheet, MCP1811BT-020/LB pinout, MCP1811BT-020/LB application, or MCP1811BT-020/LB equivalent, this page delivers verified technical context, package-specific pin functions, real-world use cases in ultra-low-power systems, and validated alternative options for design flexibility and supply continuity.

Technical Context

The MCP1811BT-020/LB belongs to the MCP1811B variant family - distinguished by absence of output discharge during shutdown and optimized for minimal leakage (5 nA typical ISHDN). Its internal PMOS pass transistor enables low dropout voltage (400 mV typical at 150 mA), stable regulation across –40°C to +85°C junction temperature, and compatibility with low-ESR ceramic capacitors without external compensation.

This device implements overcurrent protection with foldback limiting (50 mA at R_LOAD = 1 Ω) and integrates a precision bandgap reference with ±4% output voltage tolerance over load and temperature. Its thermal design targets low-power PCB layouts: the /LB suffix confirms the 4-lead 1×1 mm UDFN package with exposed thermal pad for enhanced power dissipation on JEDEC-standard 4-layer boards.

Key Specifications

Pinout & Package

Package: 4-Lead 1×1 mm UDFN with exposed thermal pad (EP), optimized for space-constrained wearables and implantables. Thermal resistance θ_JA = 91.05°C/W on JEDEC 4-layer FR4 board with thermal vias.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1811AT-020/LB, the MCP1811BT-020/LB trades output discharge capability for 2× lower shutdown current - critical for intermittent-use devices. Versus XC6210B202MR-G, it adds active enable control and uses a smaller 1×1 mm UDFN, but requires additional SHDN routing.

Availability

MCP1811BT-020/LB is available at Aetrix Electronics and suitable for wearable electronics, medical implants, and energy-harvesting sensor nodes requiring stable component supply with guaranteed long-term availability and traceable sourcing.

Supply support for MCP1811BT-020/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 with high-reliability semiconductor products.

The MCP1811X/12X product line was engineered specifically for ultra-low-power battery-operated applications - emphasizing nanoscale quiescent current, ceramic-capacitor stability, and minimal footprint to extend operational lifetime in size- and energy-constrained systems.

FAQ

What is the output voltage tolerance of the MCP1811BT-020/LB over temperature and load?

The MCP1811BT-020/LB maintains its 2.0 V nominal output within ±4% across –40°C to +85°C junction temperature and full 0–150 mA load range, as specified in the DS20006088C datasheet. This tolerance includes initial accuracy, line regulation (±20 mV), and load regulation (±25 mV), ensuring reliable operation for 2.0 V logic and analog interfaces without external trimming.

Does the MCP1811BT-020/LB require an external pull-up resistor on the SHDN pin?

No - the MCP1811BT-020/LB does not require an external pull-up on SHDN. Its internal logic threshold is defined as V_SHDN-HIGH ≥ 70% of VIN, and it draws only 0.1–0.5 nA leakage when pulled low. A standard MCU GPIO can directly drive SHDN high/low; no external resistor is needed unless open-drain control is used.

Can the MCP1811BT-020/LB operate with a 1.0 µF output capacitor at full 150 mA load?

Yes - the MCP1811BT-020/LB is explicitly characterized and guaranteed stable with a 1.0 µF X7R ceramic capacitor at 150 mA output, per Table 1-1 and Figure 2-5 in DS20006088C. This eliminates ESR requirements and enables use of low-profile, high-reliability MLCCs in space-sensitive designs.

What is the thermal performance of the MCP1811BT-020/LB in its 1×1 mm UDFN package?

In the /LB 4-lead 1×1 mm UDFN package, the MCP1811BT-020/LB achieves θ_JA = 91.05°C/W on a JEDEC-standard 4-layer FR4 board with thermal vias. At 150 mA and 5.5 V input, worst-case power dissipation is ~525 mW, resulting in ~48°C rise above ambient - well within the +85°C max junction rating when ambient remains ≤37°C.

How does the MCP1811BT-020/LB differ from the MCP1811AT-020/LB?

The MCP1811BT-020/LB omits the output discharge transistor present in the MCP1811AT-020/LB, resulting in 5 nA vs. 10 nA typical shutdown current and no VOUT discharge path when SHDN = GND. Both share identical 2.0 V output, 150 mA rating, and 1×1 mm UDFN package - selection depends solely on whether active output discharge is required.