Monolithic Power Systems Inc. MP100GN-P

Overview

MP100GN-P from Monolithic Power Systems is a compact, inductor-less offline AC/DC regulator IC designed to generate adjustable DC bias voltages (1.5V–15V) directly from universal AC mains (85–305V_RMS). It integrates a smart charging window control, internal LDO, active bleeder circuit, and power-good signaling-enabling low-component-count standby power for wireless control systems. Its 9.5Ω MOSFET R_DS(on), 120–270mA output current limit, and SOIC8E package support cost-sensitive, space-constrained off-line applications.

For engineers reviewing the MP100GN-P datasheet, MP100GN-P pinout, MP100GN-P application, or MP100GN-P equivalent, key selection criteria include its inductor-less topology, VD capacitor-based energy storage, thermal shutdown at 160°C, PG open-drain timing (200µs delay), and compatibility with full-bridge/half-wave rectifiers in wall-switch and ZigBee/Z-Wave power designs.

Technical Context

The MP100GN-P employs a proprietary smart-control architecture that activates its internal high-voltage switch only when VIN falls within a narrow charging window (typically <35V), minimizing conduction loss and enabling high efficiency at ultra-low standby loads. It uses VD as an energy reservoir-charged via VIN during low-voltage AC phases-and regulates output via an integrated LDO stage referenced to 1.235V FB voltage.

Protection logic is tightly coupled to VD voltage monitoring: over-current and short-circuit events trigger LDO shutdown when VD drops below 6.8V; VD over-voltage protection disables charging above 32.5V; and active bleeder activation below 14V ensures reliable restart after shutdown. Thermal shutdown (160°C) and hysteresis (20°C) provide autonomous die temperature management without external circuitry.

Key Specifications

Pinout & Package

MP100GN-P is housed in a thermally enhanced SOIC8E package with exposed pad (not electrically connected), requiring soldering to a GND copper pour for optimal thermal performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar offline inductor-less regulator applications.

Compared with MP101GN-P, MP100GN-P offers lower cost and identical thermal/footprint compatibility but trades 0.03% line regulation and soft-start for simplicity; versus LNK304P, it eliminates magnetics and feedback complexity but cannot provide isolation or >300mW continuous output.

Availability

MP100GN-P is available at Aetrix Electronics and suitable for wall switches and dimmers, AC/DC power supplies for wireless systems (ZigBee/Z-Wave), and standby power for general off-line applications requiring stable component supply, RoHS-compliant packaging, and long-term lifecycle continuity.

Supply support for MP100GN-P 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

Monolithic Power Systems (MPS) is a fabless semiconductor company specializing in high-performance analog and power ICs, with design centers in the US, China, and Taiwan, and manufacturing partners across Asia.

The MP100 product line delivers inductor-less AC/DC bias regulators targeting ultra-low-power, space-constrained off-line applications-including smart home controls, wireless sensors, and appliance standby circuits-where minimizing BOM count and board area is critical.

FAQ

What is the maximum recommended output voltage when using the PG pin?

The PG pin has an absolute maximum rating of 14V. Since PG is an open-drain output requiring a pull-up to VOUT, the regulated output voltage must not exceed 14V when PG functionality is enabled. For 15V output designs, PG must be left unused or disconnected.

How does the MP100GN-P achieve high efficiency without an inductor?

It uses a smart charging window technique: the internal 700V switch conducts only when rectified AC voltage falls below ~35V, charging the VD capacitor with minimal conduction loss. Energy stored in VD is then delivered to the load via a low-dropout linear regulator, eliminating switching losses and magnetic components.

Can MP100GN-P operate with a half-wave rectifier?

Yes-it supports both full-bridge and half-wave rectification. With half-wave input, output power capability is reduced by ~50% at the same VD capacitance and input voltage due to longer discharge intervals; Figure 2 in the datasheet shows derated P_OUT curves for half-wave operation.

What is the role of the NC pin (Pin 7), and can it be grounded?

Pin 7 is a true no-connect-internally unconnected and not bonded. It must remain floating; grounding or routing traces to it may introduce noise coupling or parasitic capacitance that disrupts VD voltage sensing and causes erratic startup or shutdown behavior.

Why is an X-capacitor required before the rectifier when using a variable transformer?

Variable/isolation transformers exhibit high leakage inductance (mH range). When the MP100GN-P's internal switch turns off, this inductance generates destructive voltage spikes exceeding 700V. An X-capacitor (e.g., 0.22–1µF) across the AC input clamps these spikes and ensures reliable operation per IEC 61000-4-4/5 standards.

How is thermal performance affected by the exposed pad connection?

The exposed pad is thermally conductive but electrically isolated. Soldering it to a ≥1cm² GND copper pour reduces θ_JA from 50°C/W to ~35°C/W, lowering junction temperature by up to 30°C at full load-critical for maintaining 125°C max operating junction temperature in enclosed environments.