Monolithic Power Systems Inc. MP163AGS-33-P

Overview

MP163AGS-33-P from Monolithic Power Systems is a 700V non-isolated offline primary-side regulator with integrated 700V MOSFET and 3.3V LDO, delivering up to 4W output power in buck/boost/flyback topologies. It features 210mA peak current limit, 16Ω R_DS(on), <30mW no-load consumption, and operates across –40°C to +125°C for home appliance standby power supplies.

For engineers reviewing the MP163AGS-33-P datasheet, MP163AGS-33-P pinout, MP163AGS-33-P application, or MP163AGS-33-P equivalent, key selection criteria include primary-side CV regulation without optocoupler, SOIC8-7B package thermal limits (θ_JA = 86°C/W), green-mode frequency foldback, and dual-output capability enabled by the integrated LDO.

Technical Context

The MP163AGS-33-P implements primary-side constant voltage control using feedback sampling via an external resistor divider on the FB pin referenced to a 2.55V internal bandgap, enabling optocoupler-free regulation. Its green-mode operation dynamically reduces both switching frequency and peak current under light load, achieving <30mW no-load consumption.

It integrates a 700V vertical DMOS power switch with 16Ω typical R_DS(on) and a dedicated 3.3V LDO (150mA continuous, 270mA peak) powered from the IN pin-designed to supply auxiliary rails in dual-output offline converters. Protection includes thermal shutdown (150°C trip, 30°C hysteresis), OLP (1.74V FB threshold, 175ms delay), SCP (400mA threshold), and open-loop detection (0.5V FB threshold).

Key Specifications

Pinout & Package

MP163AGS-33-P is housed in a SOIC8-7B package (7-pin variant of SOIC-8 with exposed pad omitted), optimized for high-voltage creepage and thermal performance in compact offline designs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP163BGS-33 and MP163CGS-33, the MP163AGS-33-P offers optimal cost-efficiency balance for sub-4W consumer standby applications, with lower R_DS(on) than legacy controllers and tighter 3.3V LDO tolerance (±2%) versus standard ±5% alternatives.

Availability

MP163AGS-33-P is available at Aetrix Electronics and suitable for home appliance standby power, industrial sensor interfaces, and consumer electronics auxiliary rails requiring stable component supply across multi-year production cycles.

Supply support for MP163AGS-33-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 mixed-signal ICs for power management, motion control, and automotive systems.

The MP163 product line delivers highly integrated offline regulators targeting cost-sensitive, space-constrained applications in white goods and consumer electronics - emphasizing primary-side regulation, ultra-low no-load power, and simplified system-level design.

FAQ

What is the maximum continuous output power achievable with MP163AGS-33-P in a buck topology?

The MP163AGS-33-P supports up to 4W continuous output power in buck configuration, validated at 230VAC input, 12V/200mA main output, and 5V/50mA auxiliary output. This limit arises from thermal constraints of the SOIC8-7B package (1.45W P_D(max)) and 210mA peak current limit - exceeding this requires forced airflow or larger packages like SOIC16.

How does the integrated LDO interact with the main switching regulator output?

The LDO (pin 8, OUT) is powered from the IN pin (pin 1), which is typically connected to the main buck output (e.g., 12V). It provides a regulated 3.3V rail independent of main output ripple. Its dropout voltage (≤1.1V at 150mA) means the main output must be ≥4.4V to sustain full LDO current - a series resistor on IN can reduce LDO thermal stress when main output exceeds 7V.

Can MP163AGS-33-P operate without an external VCC capacitor?

No - an external VCC capacitor (typically 1–10µF ceramic) is mandatory. The IC uses internal HV startup current from DRAIN to charge VCC until it reaches 5.6V (VCC_OFF), then switches and disables the HV source. If VCC drops below 5.3V (VCC_ON), the HV source re-engages. Without the capacitor, regulation fails due to insufficient hold-up during switching transitions.

What is the purpose of the 0.5V open-loop detection threshold on the FB pin?

The 0.5V open-loop threshold detects failed feedback paths - such as open R1/R2 resistors or disconnected sampling capacitor - preventing uncontrolled output overvoltage. When FB falls below 0.5V, the IC halts switching and initiates automatic restart after VCC discharges to VCC_PRO (2.8V), ensuring safe recovery without manual intervention.

How does frequency foldback improve light-load efficiency in MP163AGS-33-P?

Frequency foldback reduces switching frequency proportionally to load reduction - e.g., from ~65kHz at full load to <10kHz at 10mA. This cuts dynamic switching losses (proportional to f_SW) while maintaining regulation via extended off-times, directly enabling the <30mW no-load consumption required for global energy standards.

Is MP163AGS-33-P RoHS-compliant and halogen-free?

Yes - MP163AGS-33-P is lead-free, halogen-free, and fully compliant with the EU RoHS Directive 2011/65/EU. MPS confirms green status via its Quality Assurance portal, and the device carries the "P" suffix denoting lead-free packaging per J-STD-609.

What is the minimum off-time limit (τ_MINOFF) and how does it affect power capability?

τ_MINOFF is 10µs typical for MP163AGS-33-P. It sets the shortest allowable MOSFET off-period, directly limiting maximum output power in discontinuous conduction mode (DCM) per P_MAX ≈ ½·L·I_PEAK²/τ_MINOFF. Reducing τ_MINOFF increases power capability but risks instability - the value is factory-trimmed and not user-adjustable.