Monolithic Power Systems Inc. MP6922DS-LF

Overview

MP6922DS-LF from Monolithic Power Systems is a dual-channel fast turn-off intelligent synchronous rectifier controller for LLC resonant converters, driving two N-channel MOSFETs with 70mV V_DS regulation, 20ns total turn-off delay, and integrated reverse current protection (RCP). It supports CCM, CrCM, and DCM operation up to 300kHz and consumes <600µA quiescent current in light-load latch-off mode.

For engineers reviewing the MP6922DS-LF datasheet, MP6922DS-LF pinout, MP6922DS-LF application, or MP6922DS-LF equivalent, key selection criteria include its dual-channel gate drive timing precision, 180V drain-sense capability, SOIC14 package thermal performance (θ_JA = 86°C/W), and RCP latch time of 100µs - all critical for high-efficiency AC-DC adapter and telecom SMPS designs.

Technical Context

The MP6922DS-LF implements adaptive V_DS-sensing control per channel to regulate forward voltage drop at ~70mV, enabling precise MOSFET conduction timing across load conditions. Its blanking logic enforces minimum on-time (~1µs) and off-time (1.6µs) to prevent shoot-through in high-frequency LLC topologies.

It integrates independent EN and LL pins for system-level enable control and programmable light-load entry timing via external resistor, while the RCP function monitors reverse current through an internal 5V reference and latches both gate drivers for 100µs upon detection - essential for safe center-tapped full-wave rectification in CCM.

Key Specifications

Pinout & Package

MP6922DS-LF is supplied in SOIC14 package with exposed pad not present (unlike SOIC8E); thermal resistance θ_JA = 86°C/W and θ_JC = 38°C/W support industrial ambient operation up to +125°C junction temperature.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-channel synchronous rectifier controller applications.

Compared with MP6922DS-LF, MP6921DS-LF reduces channel count and eliminates RCP/LL features for cost-sensitive single-output adapters, while SRK2001P trades higher precision regulation for slower turn-off and no light-load optimization - making MP6922DS-LF optimal for high-efficiency, high-reliability dual-channel LLC systems.

Availability

MP6922DS-LF is available at Aetrix Electronics and suitable for AC-DC adapters, LCD TV power supplies, and telecom SMPS requiring stable component supply, RoHS-compliant packaging, and long-term lifecycle support.

Supply support for MP6922DS-LF 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 MP6922 product line targets high-efficiency resonant converter synchronous rectification, specifically addressing timing-critical, high-voltage secondary-side control in LLC and phase-shifted full-bridge topologies.

FAQ

What is the maximum drain voltage the MP6922DS-LF can sense?

The MP6922DS-LF supports drain voltage sensing up to 180V on both VD1 and VD2 pins, verified per Absolute Maximum Ratings table. This allows direct connection to high-voltage secondary windings in universal-input AC-DC adapters without external level-shifting circuitry.

How does the light-load latch-off function improve efficiency?

The light-load mode reduces quiescent current to <600µA by latching off both gate drivers when MOSFET conduction time falls below 2.2µs per cycle. This eliminates gate charge/discharge losses during burst-mode or no-load conditions, directly enabling compliance with Energy Star 0.5W standby requirements.

Can MP6922DS-LF drive both standard and logic-level MOSFETs?

Yes - the VG1/VG2 outputs deliver 14V high-level drive (at VDD >16V) and 0.1V low-level saturation, compatible with both standard-threshold (2–4V) and logic-level (<2V) N-channel MOSFETs. The datasheet explicitly lists this as a core feature under "Works with both Standard and Logic Level FETs".

What is the purpose of the RCP pin and how is it implemented?

The RCP pin accepts a voltage divider from the MOSFET drain to detect reverse current. When voltage exceeds 3V, the IC latches both gate drivers for 100µs to prevent shoot-through - a critical safeguard in high-frequency CCM operation of center-tapped LLC converters where body-diode conduction reversal occurs rapidly.

Does MP6922DS-LF require external components for basic operation?

Yes - minimal external components include pull-up resistors on EN and VD pins, RC network on LL pin for light-load timing, and voltage divider on RCP pin for reverse current detection. The typical application circuit shows only 3–5 passive components beyond the MOSFETs and transformer, confirming its "minimum number of readily available standard external components" design goal.

How does the 20ns turn-off delay impact LLC converter performance?

The 20ns total turn-off delay ensures precise zero-current switching in high-frequency LLC converters (>250kHz), minimizing reverse recovery losses and EMI. Measured with 5nF load and 0Ω gate resistance, this timing allows clean turn-off before drain voltage reverses - directly enabling high-efficiency operation in compact, high-power-density designs.

What thermal considerations apply to the SOIC14 package?

The SOIC14 package has θ_JA = 86°C/W and θ_JC = 38°C/W. For continuous 1.5W power dissipation (per Absolute Maximum Ratings), PCB layout must provide adequate copper area on PGND pins and avoid thermal isolation - especially critical in telecom SMPS operating at full load in +70°C ambient environments.