Monolithic Power Systems Inc. MP9989AGV-Z

Overview

MP9989AGV-Z from Monolithic Power Systems is a CCM/DCM flyback ideal diode IC integrating a 100V/10mΩ MOSFET, designed for high-side or low-side synchronous rectification in AC/DC adapters. It regulates forward voltage drop to 40mV, achieves 110µA quiescent current, and eliminates auxiliary winding requirements - enabling compact 48W USB PD and QC charger designs with up to 4A output.

For engineers reviewing the MP9989AGV-Z datasheet, MP9989AGV-Z pinout, MP9989AGV-Z application, or MP9989AGV-Z equivalent, this device delivers fast turn-off timing (25ns), ringing detection for DCM/QR stability, and dual-package support (QFN4x5-8) critical for thermal management in high-density flyback converters.

Technical Context

The MP9989AGV-Z implements adaptive gate control using slew-rate detection and blanking timers to prevent false turn-on during demagnetizing ringing in DCM/QR modes. Its internal linear regulator generates VDD from SENSE without auxiliary winding, supporting operation from 0V output.

It operates across CCM, DCM, and quasi-resonant flyback topologies with precise thresholds: -80mV turn-on, -3mV turn-off, and 1.2µs turn-on blanking. The integrated 100V MOSFET features R_DS(ON) = 10mΩ at 25°C and single-pulse avalanche energy of 20mJ.

Key Specifications

Pinout & Package

MP9989AGV-Z is housed in a thermally enhanced QFN4x5-8 package with exposed thermal pad, optimized for high-power density flyback secondary-side layouts. Pin functions are identical across SOIC-8 and QFN variants per datasheet Rev. 1.1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar flyback synchronous rectifier applications.

Compared with NCP4307DR2G and SiHP065N10AD, MP9989AGV-Z uniquely integrates control, 100V switching, and self-biasing in one QFN package - reducing component count by 3+ parts and enabling smaller, cooler-running adapters without sacrificing CCM/DCM/QR flexibility.

Availability

MP9989AGV-Z is available at Aetrix Electronics and suitable for laptop adapters, USB PD chargers, and high-efficiency flyback converters requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MP9989AGV-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 power management ICs, with design centers in the US, China, and Taiwan.

The MP9989 belongs to MPS's intelligent rectifier product line, engineered specifically to replace Schottky diodes in flyback converters while eliminating auxiliary windings and maximizing efficiency across CCM, DCM, and QR modes.

FAQ

What is the maximum continuous output current supported by MP9989AGV-Z in a typical 48W adapter?

In a well-designed 48W flyback adapter with adequate PCB copper area and thermal vias, MP9989AGV-Z supports up to 4A continuous output current. This is validated in MPS application note AN-106, where the QFN4x5-8 package achieves 17.8A at 100°C case temperature - sufficient for 4A at ≤85°C ambient with standard 2oz copper and 6 thermal vias under the exposed pad.

Does MP9989AGV-Z require an external resistor on the SENSE pin, and if so, what value is recommended?

Yes - an external resistor between SENSE and the MOSFET drain is recommended to limit negative overvoltage stress during body-diode conduction. MPS specifies 100Ω to 300Ω; 220Ω is optimal for most 48W–65W adapters, balancing VDD supply stability and V_DS slew rate integrity without compromising turn-on responsiveness.

Can MP9989AGV-Z operate in both high-side and low-side rectification configurations?

Yes - MP9989AGV-Z supports both configurations. In high-side setups, VS connects to output rail and VD to transformer secondary; in low-side, VS ties to ground and VD to transformer center-tap or secondary return. The datasheet provides Figure 3 (low-side) and Figure 4 (high-side) schematics with matching PCB layout guidelines for each.

How does the slew-rate detection function prevent false turn-on during DCM ringing?

The IC monitors dV_DS/dt during negative transitions. If V_DS crosses the -80mV threshold but the slew rate is below the internal threshold (requiring >2V change within 30ns), the turn-on timer expires without triggering gate drive. This rejects slow ringing artifacts while preserving fast, valid turn-on events - confirmed in Figure 2 timing diagram and AN-106 test waveforms.

What is the purpose of the turn-on blanking time, and how is it implemented?

The 1.2µs turn-on blanking time prevents premature turn-off caused by voltage spikes during MOSFET conduction. Once the gate turns on, the controller ignores V_DS feedback for this duration unless V_DS rises above 1.8V - indicating abnormal conduction. This ensures stable on-state operation during transient load steps and magnetic reset events, as verified in 48W flyback test data on page 7 of the datasheet.

Is MP9989AGV-Z compliant with RoHS and halogen-free standards?

Yes - MP9989AGV-Z is lead-free, halogen-free, and fully compliant with the EU RoHS directive (2011/65/EU). MPS confirms green status on its website under Quality Assurance, and the device carries the "RoHS Compliant" marking on its top-side laser etch per JEDEC J-STD-020 moisture sensitivity level 2a handling requirements.