Monolithic Power Systems Inc. MP163BGSE-33-Z

Overview

MP163BGSE-33-Z from Monolithic Power Systems is a 700V non-isolated offline primary-side regulator with integrated 700V MOSFET and 3.3V LDO, supporting buck/boost/flyback topologies for dual-output CV regulation without optocoupler. Typical peak current limit is 420mA, R_DS(on) is 14Ω, no-load power consumption is <30mW, and max output power is 4W - used in home appliance standby supplies and white-goods auxiliary rails.

For engineers reviewing the MP163BGSE-33-Z datasheet, MP163BGSE-33-Z pinout, MP163BGSE-33-Z application, or MP163BGSE-33-Z equivalent, key selection criteria include primary-side CV accuracy, integrated HV MOSFET voltage rating, LDO dropout performance at 150mA, green-mode frequency foldback behavior, and SOIC16 thermal resistance (θ_JA = 80°C/W).

Technical Context

The MP163BGSE-33-Z implements primary-side constant voltage control using sampled feedback from a secondary-side capacitor, eliminating optocoupler dependency. Its internal error amplifier compares FB voltage to a 2.55V reference and adjusts switching on-time via peak-current limiting.

Green-mode operation dynamically reduces both peak current and switching frequency under light load, enabled by τ_minoff = 12μs and τ_maxon = 24μs timing constraints, while ramp compensation and leading-edge blanking (180ns) ensure stable CCM/DCM transitions across line/load variations.

Key Specifications

Pinout & Package

MP163BGSE-33-Z is housed in a 16-pin SOIC package with exposed pad (SOIC16), rated for 1.56W continuous power dissipation at T_A = +25°C and θ_JA = 80°C/W.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP163BGSE-33-Z, MP163CGSE-33-Z delivers higher power capability at the cost of slightly higher no-load current, while MP163BGSE-5-Z preserves identical topology support and thermal profile but shifts LDO voltage - both require revalidation of feedback divider and dummy load values.

Availability

MP163BGSE-33-Z is available at Aetrix Electronics and suitable for home appliance control boards, white-goods auxiliary power supplies, and IoT hub standby circuits requiring stable component supply across multi-year production cycles.

Supply support for MP163BGSE-33-Z 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 global distribution through authorized partners.

The MP163 product line targets cost-sensitive, low-power offline AC/DC conversion in consumer and industrial applications, emphasizing integration, efficiency, and regulatory compliance without compromising reliability.

FAQ

What is the minimum recommended input capacitance for MP163BGSE-33-Z in universal AC applications?

For universal AC input (85–265V AC) with full-wave rectification, the minimum input capacitance is 1.5µF per watt of output power. For a 4W design, this equals 6µF minimum. Use low-ESR electrolytic or polymer capacitors rated for ≥400V DC with ripple current handling exceeding 1.2× output current.

Can MP163BGSE-33-Z operate in continuous conduction mode (CCM) at full load?

Yes - MP163BGSE-33-Z supports CCM operation at full load when inductance is selected to keep peak current below 420mA and minimum off time above 12µs. Equation (7) in the datasheet confirms CCM power capability depends on L, V_OUT, and τ_minoff; typical designs use 1–2mH for 12V/300mA outputs.

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

The LDO (pin IN → OUT) is powered from the main converter's high-side output (e.g., buck output). Its input voltage must exceed 4.3V to regulate 3.3V at 150mA. Excess voltage drops across the LDO pass element, so thermal design must account for (V_{IN_LDO} − 3.3V) × I_LOAD power dissipation in the SOIC16 package.

What is the purpose of the EN pin, and what happens during LDO shutdown?

The EN pin enables or disables the integrated LDO only - it does not affect the main switching regulator. When EN is pulled low (<1.07V), LDO output shuts down and draws just 9µA. The main controller continues switching and regulating the primary output, allowing independent power sequencing of digital and analog subsystems.

Is an external dummy load required, and how is its value determined?

Yes - a minimum 3mA dummy load is required on the main output to ensure sufficient inductor energy for sampling capacitor charging and FB voltage stability. Value is calculated as R_DUMMY = V_OUT/0.003A; for 12V output, use 4kΩ 0.25W resistor. Reduce value if light-load regulation degrades, but verify no-load power remains <30mW.

Does MP163BGSE-33-Z support ZVS or QR operation?

No - MP163BGSE-33-Z uses fixed-frequency peak-current-mode control with frequency foldback, not valley-switching or quasi-resonant control. It operates in CCM or DCM based on inductance and load, but lacks zero-voltage switching detection circuitry or variable-frequency resonance timing.

How is open-loop protection triggered, and can it be disabled?

Open-loop protection activates when FB voltage falls below 0.5V for >100ms, indicating loss of feedback signal or output short. It cannot be disabled - the IC forces restart after VCC discharge to V_CCpro (2.8V). This is a safety-critical feature per IEC 62368-1 and must remain functional in certified designs.