Monolithic Power Systems Inc. MP175GS-Z

Overview

MP175GS-Z from Monolithic Power Systems is a 700V primary-side constant-voltage (CV) offline regulator with integrated 700V/4.5Ω MOSFET, supporting buck, buck-boost, boost, and flyback topologies. It delivers up to 600mA output current in CCM, achieves <30mW no-load consumption, and operates in green-mode with frequency foldback and peak-current compression. It targets non-isolated AC/DC power supplies for home appliances and standby power.

For engineers reviewing the MP175GS-Z datasheet, MP175GS-Z pinout, MP175GS-Z application, or MP175GS-Z equivalent, key selection criteria include primary-side CV regulation without optocoupler, SOIC-8 package thermal performance, 700V drain rating, fixed/adjustable output configuration, and integrated protection suite (OTP, SCP, OLP, BOP, OLD).

Technical Context

The MP175GS-Z implements primary-side regulation using VCC or FB feedback-internal 500kΩ lower divider enables fixed-output mode when FB is unconnected; external resistor divider overrides it for adjustable output. Its green-mode operation dynamically scales switching frequency and peak current limit downward under light load to maintain high average efficiency.

Start-up relies on an internal 700V high-voltage current source charging the VCC capacitor from DRAIN; UVLO (VCCL = 7–8.7V) and HV regulator hysteresis (VHVon/VHVoff = 7.9–9.6V) ensure robust turn-on/turn-off sequencing. Protection logic includes 8192-cycle OLP counter, SCP threshold at 135–175% of ILimit, and open-loop detection triggered below VOLD = 0.2–0.4V.

Key Specifications

Pinout & Package

MP175GS-Z is housed in a standard SOIC-8 package (JEDEC MS-012, variation AA) with exposed DRAIN pins (5–8) for enhanced thermal dissipation. The package supports surface-mount assembly and meets RoHS, lead-free, and halogen-free requirements.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP174GS-Z and LNK3206G, MP175GS-Z delivers higher integration (700V MOSFET + HV current source), better light-load efficiency (<30mW no-load vs. ≥80mW), and tighter CV regulation-making it optimal for new designs targeting global energy standards and compact form factors.

Availability

MP175GS-Z is available at Aetrix Electronics and suitable for home appliance control boards, industrial sensor transmitters, and LED lighting auxiliary supplies requiring stable component supply, long-lifecycle support, and RoHS-compliant manufacturing.

Supply support for MP175GS-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 MP175 product line targets cost-sensitive, non-isolated offline AC/DC conversion-designed specifically for low-power (<10W) applications where optocoupler-free primary-side regulation, green-mode efficiency, and integrated protection are critical.

FAQ

What topologies does MP175GS-Z support?

The MP175GS-Z supports buck, buck-boost, boost, and flyback topologies in non-isolated configurations. Its primary-side CV regulation architecture eliminates the need for optocouplers or secondary-side feedback, enabling simplified designs across all four topologies with shared component selection rules for inductors, diodes, and capacitors.

How does MP175GS-Z achieve <30mW no-load consumption?

MP175GS-Z achieves <30mW no-load consumption through green-mode operation: switching frequency and peak current limit scale downward under light load, reducing dynamic losses; combined with low VCC operating current (220–400μA) and internally biased VCC, it minimizes quiescent power without auxiliary windings or external bias circuits.

Can MP175GS-Z be used in isolated designs?

No-MP175GS-Z is explicitly designed for non-isolated offline regulators. Its internal architecture ties VCC and FB references to the primary side, and it lacks isolation-enabling features like transformer-coupled feedback or reinforced insulation ratings. For isolated applications, MPS recommends the MP173 or MP176 series.

What is the role of GNDA and GNDP pins?

GNDA is the analog ground reference for FB and internal sensing circuits; GNDP is the power ground return for the internal MOSFET source and high-current paths. They must be shorted externally but kept as separate copper pours on the PCB to prevent noise from power switching from corrupting feedback accuracy and regulation stability.

Does MP175GS-Z require a minimum load?

Yes-a dummy load is recommended to maintain regulation under no-load conditions. The IC switches at minimum frequency and delivers residual power; without a load, output voltage may rise beyond specification. A 1–5mA resistive dummy load ensures stable regulation and predictable protection behavior during startup and fault recovery.

How is over-temperature protection implemented?

MP175GS-Z integrates a thermal sensor that triggers shutdown when junction temperature exceeds 150°C. The protection is non-latching: after shutdown, the device cools passively and automatically resumes operation once die temperature falls below the hysteresis threshold (~140°C), ensuring self-recovery without manual reset.

What layout practices improve EMI performance?

Minimize the high-di/dt loop formed by CIN, DRAIN, freewheeling diode, inductor, and COUT; place a 1nF bypass capacitor between FB and GNDA close to the IC; use large copper pour on DRAIN pins for thermal and EMI control; keep AC input traces short and shielded; and separate GNDA/GNDP ground planes until single-point connection near CIN.