Monolithic Power Systems Inc. MP163BGS-33-P

Overview

MP163BGS-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 420mA peak current limit, 14Ω R_DS(on), <30mW no-load consumption, and supports home appliance standby power and white-goods auxiliary supplies.

For engineers reviewing the MP163BGS-33-P datasheet, MP163BGS-33-P pinout, MP163BGS-33-P application, or MP163BGS-33-P equivalent, key selection criteria include primary-side CV regulation without optocoupler, SOIC8-7B package thermal limits (1.45W), green-mode frequency foldback, and dual-output capability enabled by the integrated LDO.

Technical Context

The MP163BGS-33-P implements primary-side constant voltage control using sampled feedback from a secondary-side capacitor, eliminating optocoupler dependency. Its internal 700V MOSFET operates with peak-current compression and frequency foldback to maintain efficiency down to light load.

It integrates an LDO with 3.3V ±2% output, 270mA peak current capability, and dropout voltage of 620–1100mV at 150mA. Protection includes thermal shutdown (150°C), OLP (220ms delay), SCP (600mA threshold), UVLO (5.1–5.8V turn-on), and open-loop detection (<0.5V FB).

Key Specifications

Pinout & Package

MP163BGS-33-P is housed in a SOIC8-7B package (7-pin variant with 1 pin unused), optimized for compact offline regulator designs with integrated high-voltage switching and LDO functions.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP163AGS-33, MP163BGS-33-P delivers 100% higher peak current and 12.5% lower R_DS(on) in the same footprint, enabling 4W operation without package upgrade; versus MP163CGS-33, it trades 33% lower peak current for improved thermal margin in space-constrained designs.

Availability

MP163BGS-33-P is available at Aetrix Electronics and suitable for home appliance control, white goods auxiliary power, and consumer electronics standby power requiring stable component supply across extended production lifecycles.

Supply support for MP163BGS-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 power ICs, with design centers in the US, China, and Taiwan.

The MP163 product line targets cost-sensitive, space-constrained offline AC/DC conversion in consumer and industrial applications, emphasizing integration, efficiency, and regulatory compliance without optical feedback.

FAQ

What is the maximum continuous output power achievable with MP163BGS-33-P in SOIC8-7B package?

The MP163BGS-33-P supports up to 4W continuous output power in SOIC8-7B, validated under TA = +25°C with θJA = 86°C/W and maximum junction temperature of 150°C. Derating is required above 50°C ambient; at 70°C, maximum sustainable power drops to ~2.5W due to thermal limits.

Does MP163BGS-33-P require an external optocoupler for output voltage regulation?

No. MP163BGS-33-P uses primary-side constant voltage (CV) regulation with internal sampling of the output voltage via a feedback capacitor network. This eliminates the need for an optocoupler, simplifying design and improving long-term reliability in consumer-grade applications.

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

The LDO (pin IN → OUT) accepts its input from the main converter's high-side output (e.g., 12V buck rail) and regulates it to 3.3V. Its 620–1100mV dropout requires ≥3.92V input at 150mA load. An external series resistor on IN mitigates thermal stress when input-to-output differential exceeds 5V.

What protection mechanisms activate during a short-circuit event on the main output?

During main output short-circuit, MP163BGS-33-P triggers short-circuit protection (SCP) when sensed peak current exceeds 600mA. The MOSFET shuts off immediately, VCC discharges to ~2.8V, and after a latch-off period (~16–24μA discharge current), the IC auto-restarts once VCC recharges above 5.1V.

Can MP163BGS-33-P operate with universal AC input (90–264VAC)?

Yes. With proper input capacitor sizing (≥2µF/W for full-wave rectification) and inductor selection, MP163BGS-33-P supports universal AC input. Its 700V MOSFET withstands 264VAC × √2 ≈ 373V peak plus surge margins, and green-mode operation maintains efficiency across the full input range.

Is there a recommended minimum dummy load for stable regulation at light load?

A 3mA dummy load is recommended to ensure sufficient inductor energy for reliable sampling of the output voltage by the feedback capacitor. This prevents regulation loss at no-load, especially critical for applications requiring tight CV accuracy below 10% load.

What is the function of the EN pin on MP163BGS-33-P, and is it present in SOIC8-7B?

The EN pin enables/disables the integrated LDO. However, MP163BGS-33-P in SOIC8-7B package does not expose EN-it is only available in SOIC16 variants (e.g., MP163BGSE-33). In SOIC8-7B, the LDO operates continuously when VCC is valid and FB is within regulation range.