Monolithic Power Systems Inc. MP163AGS-5-P

Overview

MP163AGS-5-P from Monolithic Power Systems is a 700V non-isolated offline primary-side regulator with integrated 700V MOSFET and 5V LDO, supporting buck/boost/flyback topologies for dual-output CV regulation without optocoupler. It delivers up to 4W output power, achieves <30mW no-load consumption, and features green-mode operation with frequency foldback and peak-current compression. Used in home appliance standby supplies and white-goods auxiliary rails.

For engineers reviewing the MP163AGS-5-P datasheet, MP163AGS-5-P pinout, MP163AGS-5-P application, or MP163AGS-5-P equivalent, key selection criteria include its SOIC8-7B package, 210mA peak current limit, 16Ω R_DS(on), 5V LDO output with 1100mV dropout at 150mA, and integrated thermal/OLP/SCP protection.

Technical Context

The MP163AGS-5-P implements primary-side constant-voltage control using sampled feedback from a secondary-side capacitor, eliminating optocoupler dependency. Its internal 700V MOSFET operates with programmable peak-current limiting (210mA typ) and leading-edge blanking (350ns), while the integrated LDO provides regulated 5V output referenced to SOURCE.

Green-mode operation dynamically reduces both switching frequency and peak current under light load, enabling <30mW no-load power consumption. Protection logic includes open-loop detection (FB < 0.5V), OLP with 175ms delay, and thermal shutdown at 150°C with 30°C hysteresis.

Key Specifications

Pinout & Package

MP163AGS-5-P is housed in an SOIC8-7B package with 7 active terminals (Pin 3 is NC). The exposed pad is electrically connected to SOURCE and serves as primary thermal path.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP163AGS-5-P, MP163AGSE-5 offers enable control and better thermal dissipation in SOIC16, while MP163BGS-5 delivers higher power capability in the same SOIC8-7B footprint-enabling scalable design reuse across 4W and 7W product tiers.

Availability

MP163AGS-5-P is available at Aetrix Electronics and suitable for home appliance control boards, white-goods standby supplies, and industrial sensor hub PSUs requiring stable component supply and long-term lifecycle support.

Supply support for MP163AGS-5-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 focus on efficiency, integration, and reliability.

The MP163 product line targets cost-sensitive, low-power offline AC/DC conversion, emphasizing primary-side regulation, green-mode operation, and integrated power stages for consumer and industrial applications.

FAQ

What is the maximum continuous output power achievable with MP163AGS-5-P in buck topology?

The MP163AGS-5-P supports up to 4W continuous output power in buck configuration under typical conditions (230VAC input, 25°C ambient, SOIC8-7B on 2-layer PCB with 1-in² copper pour). This limit arises from thermal constraints due to its 16Ω R_DS(on) and 1.45W package power dissipation rating-not from current or voltage headroom.

Does MP163AGS-5-P require an external optocoupler for output voltage regulation?

No. MP163AGS-5-P uses primary-side constant-voltage regulation with internal sampling of the secondary-side output capacitor voltage via a dedicated feedback network. This eliminates the need for optocoupler, TL431, or secondary-side sensing components-reducing BOM cost and improving reliability.

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

The LDO input (IN pin) is typically connected to the main buck output (e.g., 12V rail). It regulates down to 5V with 1100mV dropout at 150mA. Power dissipation in the LDO is managed by limiting input–output differential and using external series resistors to share voltage drop-critical for thermal performance in high-input-differential cases.

What is the purpose of the GND and SOURCE pins being separate in MP163AGS-5-P?

GND is the dedicated ground return for the integrated LDO output (OUT), while SOURCE serves as the power MOSFET source and ground reference for VCC and FB circuits. Separating them prevents LDO load transients from modulating the feedback reference, improving regulation accuracy and PSRR-especially critical in dual-rail systems.

Can MP163AGS-5-P operate in flyback topology, and what design changes are required?

Yes. In flyback mode, the DRAIN pin connects to the primary winding, SOURCE to primary ground, and FB senses reflected output voltage via an RC network. Key changes include adjusting feedback resistor values to account for turns ratio, adding snubber across primary, and ensuring transformer reset capability-per MPS AN-107 application note.

What is the significance of the 175ms OLP delay time, and how does it affect system behavior?

The 175ms overload protection delay prevents false triggering during inrush or transient overloads. If FB voltage remains below 1.74V for ≥175ms, the IC latches off and restarts after VCC discharges to VCCpro (2.8V). This timing aligns with typical appliance motor startup durations, allowing safe temporary overloads without shutdown.

How does the green-mode operation reduce no-load power consumption below 30mW?

Green-mode reduces both switching frequency and peak current under light load. As output current drops, off-time increases, lowering frequency; simultaneously, peak-current compression reduces energy per cycle. Combined with <200μA quiescent ICC and efficient HV startup, this achieves <30mW no-load consumption-verified at 230VAC input per datasheet Figure 11.