Microchip Technology MCP1812AT-020/LT

Overview

MCP1812AT-020/LT from Microchip Technology is a 300 mA ultra-low quiescent current (250 nA typical) fixed-output 2.0 V low-dropout linear regulator in a 3-lead SOT-23 package, featuring output discharge during shutdown and stable operation with only 2.2 µF ceramic output capacitance - designed for energy harvesting and long-life battery-powered medical and wearable electronics.

For engineers reviewing the MCP1812AT-020/LT datasheet, MCP1812AT-020/LT pinout, MCP1812AT-020/LT application, or MCP1812AT-020/LT equivalent, key selection criteria include ultra-low IQ (250 nA), 2.0 V fixed output, 300 mA load capability, 400 mV dropout at full load, and output discharge functionality - all critical for sleep-mode power integrity in constrained-energy systems.

Technical Context

The MCP1812AT-020/LT implements a PMOS pass transistor architecture enabling ultra-low quiescent current and fast start-up (400 µs delay from SHDN). Its internal error amplifier and feedback network maintain ±4% output voltage accuracy across –40°C to +85°C junction temperature and load currents up to 300 mA.

It integrates an active discharge transistor (RDCH = 100 Ω typical) that pulls VOUT to GND when SHDN = GND, preventing residual voltage hold-up on downstream circuitry - a feature exclusive to MCP1812A variants and absent in MCP1812B.

Key Specifications

Pinout & Package

Package: 3-Lead SOT-23 (JEDEC MO-178AA), 2.92 mm × 1.6 mm × 1.1 mm body, surface-mount, lead-free and RoHS compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1812AT-2002E/MB, the MCP1812AT-020/LT offers identical electrical specs in a smaller 3-lead SOT-23 footprint but lower thermal performance; versus XC6210B202MR-G, it adds essential output discharge at the cost of +1.2 µF output capacitance - a necessary trade-off for robust power sequencing in safety- or security-sensitive applications.

Availability

MCP1812AT-020/LT is available at Aetrix Electronics and suitable for energy harvesting systems, wearable medical sensors, and smart card readers requiring stable component supply with guaranteed long-term manufacturability and traceable sourcing.

Supply support for MCP1812AT-020/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, analog, FPGA, and mixed-signal semiconductors headquartered in Chandler, Arizona.

The MCP181X/12X product line was engineered specifically for ultra-low-power, battery-constrained applications - emphasizing nanoscale quiescent current, ceramic-capacitor compatibility, and integrated power sequencing features like output discharge.

FAQ

What is the maximum input voltage rating for the MCP1812AT-020/LT?

The MCP1812AT-020/LT has an absolute maximum input voltage rating of +6.0 V. However, its specified operating input voltage range is 1.8 V to 5.5 V. Exceeding 5.5 V may cause permanent damage or violate reliability specifications, even if below the 6.0 V absolute maximum. Always operate within the 1.8–5.5 V range for guaranteed performance and lifetime compliance.

Does the MCP1812AT-020/LT require an external resistor divider to set the output voltage?

No, the MCP1812AT-020/LT does not require an external resistor divider. It is a fixed-output LDO with a factory-trimmed 2.0 V regulation voltage. The "020" in the part number explicitly denotes the 2.0 V variant. All feedback resistors are internal, eliminating layout complexity and ensuring ±4% output accuracy over temperature and load without external components.

Is output discharge supported on the MCP1812AT-020/LT, and how does it function?

Yes, output discharge is fully supported on the MCP1812AT-020/LT. When the SHDN pin is pulled low (≤20% VIN), an internal 100 Ω discharge transistor connects VOUT to GND, actively pulling the output voltage to <100 mV within microseconds. This feature is inherent to the "A" suffix (MCP1812A), distinguishing it from the "B" variant which omits discharge.

What is the minimum recommended output capacitance for stable operation of the MCP1812AT-020/LT?

The minimum recommended output capacitance for stable operation of the MCP1812AT-020/LT is 2.2 µF ceramic (X7R or better dielectric). This value is required to ensure phase margin >45° and prevent oscillation under all load and temperature conditions. Using less than 2.2 µF - including 1.0 µF - risks instability, especially at light loads or elevated temperatures, and is not validated per the DS20006088C datasheet.

Can the MCP1812AT-020/LT be used with a 1.5 V alkaline battery as the input source?

No, the MCP1812AT-020/LT cannot reliably regulate from a 1.5 V alkaline battery. Its minimum operating input voltage is 1.8 V (per datasheet Section 1.0, "Input Operating Voltage"), and its dropout voltage is 400 mV at 300 mA. To deliver 2.0 V output, VIN must remain ≥2.4 V - well above the 1.5 V nominal and rapidly declining voltage of a single alkaline cell. Use two alkaline cells (2.0–3.2 V) or a Li-ion cell instead.