Microchip Technology MCP1811BT-030/LT

Overview

MCP1811BT-030/LT from Microchip Technology is a 150 mA ultra-low quiescent current (250 nA typical) fixed 3.0V output LDO linear regulator in 3-lead SOT-23 package, designed for energy harvesting and long-life battery-powered systems requiring stable low-noise voltage regulation with ceramic capacitor support (1.0 µF min). It features shutdown mode (5 nA typical IQ), overcurrent protection, and output discharge capability.

For engineers reviewing the MCP1811BT-030/LT datasheet, MCP1811BT-030/LT pinout, MCP1811BT-030/LT application, or MCP1811BT-030/LT equivalent, key selection criteria include ultra-low shutdown current, 3.0V fixed output accuracy (±4%), dropout voltage at full load (600 mV max), stability with minimal ceramic capacitance, and compatibility with wearable and medical sensor nodes.

Technical Context

The MCP1811BT-030/LT implements a PMOS pass transistor architecture enabling ultra-low quiescent current operation and fast start-up (400 µs typical delay from SHDN). Its internal error amplifier and reference maintain ±4% output voltage tolerance across -40°C to +85°C junction temperature and load currents up to 150 mA.

It integrates an active discharge transistor (RDCH = 100 Ω typical) that pulls VOUT to GND during shutdown (SHDN = GND), preventing residual voltage hold-up in power-gated subsystems - a critical feature for energy-harvesting systems where stored charge must be fully cleared between wake cycles.

Key Specifications

Pinout & Package

Package: 3-Lead SOT-23 (SC-59), JEDEC MO-178AA, 2.92 mm × 1.3 mm × 1.0 mm body, exposed pad not present.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1811AT-300/LT, the MCP1811BT-030/LT offers 5× lower shutdown current for superior energy harvesting retention; versus XC6210B302MR-G, it provides integrated discharge in a 3-pin form factor ideal for space- and leakage-sensitive wearables.

Availability

MCP1811BT-030/LT 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 availability and traceable sourcing.

Supply support for MCP1811BT-030/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 is a leading provider of microcontroller, analog, FPGA, and memory solutions, with a strong focus on low-power and embedded control applications.

The MCP1811 family is engineered specifically for ultra-low-power battery and energy-harvesting systems, delivering industry-leading quiescent current performance without sacrificing output accuracy or transient response.

FAQ

What is the maximum input voltage rating for the MCP1811BT-030/LT?

The MCP1811BT-030/LT has an absolute maximum input voltage rating of +6.0V. However, its operational input voltage range is specified from 1.8V to 5.5V. Exceeding 5.5V may cause permanent damage or violate safe operating area limits, especially under high ambient temperatures. Always ensure VIN remains within 1.8V–5.5V during normal operation to guarantee reliability and parametric compliance for the MCP1811BT-030/LT.

Does the MCP1811BT-030/LT require an external pull-up resistor on the SHDN pin?

Yes - the SHDN pin of the MCP1811BT-030/LT is active-low and internally unconnected. A pull-up resistor (typically 1 MΩ to VIN) is required to maintain normal operation. Without it, the device remains in shutdown mode. This design allows direct interfacing with open-drain GPIOs or logic controllers, and the MCP1811BT-030/LT datasheet confirms 1 MΩ as the recommended value for reliable turn-on behavior.

Can the MCP1811BT-030/LT be used with a 0.47 µF output capacitor?

No - the MCP1811BT-030/LT requires a minimum of 1.0 µF ceramic (X7R) output capacitance for guaranteed stability across all operating conditions. Using 0.47 µF risks oscillation, poor load transient response, and potential output voltage overshoot. The datasheet explicitly specifies 1.0 µF as the minimum stable value, and this requirement applies directly to the MCP1811BT-030/LT regardless of load current or temperature.

What is the thermal resistance (θJA) of the MCP1811BT-030/LT in its SOT-23 package?

The MCP1811BT-030/LT in the 3-lead SOT-23 package has a thermal resistance θJA of 211.33°C/W when mounted on a JEDEC-standard 4-layer FR4 board with 1 oz. copper. This value assumes no thermal vias or enhanced copper pours. For continuous 150 mA operation at high ambient temperatures, derating is essential - e.g., at TA = 60°C, maximum allowable power dissipation drops to ~315 mW before reaching TJ = 85°C, confirming the need for careful thermal design around the MCP1811BT-030/LT.

Is the output voltage of the MCP1811BT-030/LT trimmed at the factory?

Yes - the MCP1811BT-030/LT features factory-trimmed output voltage set to 3.0V with ±4% tolerance over temperature (-40°C to +85°C) and line/load conditions. This trimming is performed during final test and does not rely on external resistors. The 3.0V nominal value is laser-trimmed into the internal reference, ensuring consistent performance across units without calibration - a key reliability attribute for the MCP1811BT-030/LT in high-volume consumer and medical deployments.