Monolithic Power Systems Inc. MP024GS-10

Overview

MP024GS-10 from Monolithic Power Systems is a primary-side, constant-current/constant-voltage (CC/CV) flyback regulator with integrated 700V MOSFET and high-voltage start-up current source. It delivers accurate output regulation for low-power offline adapters without optocoupler or secondary feedback, supports programmable cable compensation, operates in DCM with variable off-time control, and achieves <30mW no-load power consumption - used in 5V/2A cell phone chargers.

For engineers reviewing the MP024GS-10 datasheet, MP024GS-10 pinout, MP024GS-10 application, or MP024GS-10 equivalent, key selection criteria include its 700V/4.5Ω integrated MOSFET, VCC UVLO thresholds (19.4V on / 8.7V off), FB reference voltage (3.96V), programmable CP-based cable compensation, and full protection suite (OVP, OLP, OTP, SSP, OCkP, VCC UVLO).

Technical Context

The MP024GS-10 implements primary-side regulation using zero-current detection (ZCD) with 100mV threshold to enforce discontinuous conduction mode (DCM), eliminating need for auxiliary winding sensing. Its variable off-time peak-current control modulates switching frequency between 75Hz and 54kHz to maintain CV/CC regulation while shaping EMI spectrum naturally.

Feedback is derived from an auxiliary winding via FB pin, with sampling time configurable via SS pin resistor (180–360ns typical) and dynamically adjusted during load transitions. Cable compensation is implemented by sinking current into FB proportional to CP voltage - enabled only when CP is connected directly to a 1µF capacitor, not via resistors.

Key Specifications

Pinout & Package

MP024GS-10 is housed in a SOIC8-7B package - an industry-standard 8-pin surface-mount outline with 7 functional pins (pin 3 omitted) and 0.65mm pitch, optimized for compact offline SMPS layouts with thermal pad exposure on underside.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar primary-side CC/CV flyback regulator applications.

Compared with MP024GS-10, MP023GS-10 removes CP functionality but retains identical regulation accuracy and thermal performance, while INN2214K adds safety features and EMI support at the cost of higher system complexity and reduced design flexibility in cable-compensated consumer adapters.

Availability

MP024GS-10 is available at Aetrix Electronics and suitable for smartphone charging adapters, USB-C wall adapters, IoT device power supplies, and Bluetooth headset chargers requiring stable component supply, long-term lifecycle support, and RoHS-compliant manufacturing.

Supply support for MP024GS-10 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 MP024 series targets cost-sensitive, low-power offline AC/DC conversion - designed specifically for primary-side regulated chargers and adapters where simplicity, reliability, and energy efficiency are paramount.

FAQ

What is the maximum continuous output power achievable with MP024GS-10 in a non-ventilated adapter?

The MP024GS-10 delivers up to 7.5W continuous output power in a non-ventilated enclosed adapter at 50°C ambient temperature with 5V output, limited by thermal shutdown at 140°C junction temperature. This rating assumes SOIC8-7B mounting on a standard 4-layer PCB with 2oz copper and minimal thermal relief.

How does the programmable cable compensation function work, and what external components are required?

Cable compensation requires a 1µF ceramic capacitor connected directly from CP to GND. The IC generates a switching signal proportional to current limit and duty cycle, filtered by the capacitor to produce a DC voltage (V_CP). This voltage controls current sinking into FB, adjusting the upper resistor's effective value to offset voltage drop across the cable - no external resistors on CP are permitted.

Can MP024GS-10 operate with universal AC input (85–265VAC), and what is the minimum bulk capacitor requirement?

Yes, MP024GS-10 supports universal AC input due to its 700V integrated MOSFET and HV start-up current source. For universal input, bulk capacitance should be 2–3µF per watt (e.g., 20–30µF for 10W). At 230VAC single-range, capacitance may be halved. Minimum DC bus voltage must satisfy Equation (11) to avoid current limitation under low-line conditions.

What protection features are built into MP024GS-10, and how do they behave during fault conditions?

MP024GS-10 includes VCC UVLO, OVP (5.96V FB threshold), OLP (128-cycle FB undershoot detection), OTP (140°C shutdown with 40°C hysteresis), SSP (t_ONmax = 40µs limit), and OCkP (open-loop monitoring). All protections trigger immediate hiccup-mode shutdown - drive pulses cease until fault clears and VCC recycles through UVLO band.

Is MP024GS-10 compatible with synchronous rectification, and which controller pairs with it?

MP024GS-10 is fully compatible with synchronous rectification. The MP6906 - an adaptive, high-speed SR controller in SOT23-6 - is recommended for 5V outputs. It senses secondary-side voltage transitions and drives an external MOSFET, improving efficiency by 3–4% over Schottky diodes without requiring auxiliary winding sensing.

What is the purpose of the SS pin, and how does resistor selection affect regulation accuracy?

The SS pin selects FB sampling time (180–360ns typical) via external resistor to align sampling with the end of secondary diode conduction. Correct timing ensures accurate auxiliary voltage measurement - too early causes over-regulation; too late causes under-regulation. Resistor values are specified in the Electrical Characteristics table (page 5) and must be selected based on transformer turns ratio and operating frequency.

Does MP024GS-10 require a minimum load to maintain regulation stability?

No minimum load is required. The MP024GS-10 maintains stable CV/CC regulation down to zero load, achieving <30mW no-load consumption via frequency reduction and burst-mode operation. Light-load efficiency is preserved by minimizing gate drive losses and disabling non-essential internal blocks during extended off-times.