Monolithic Power Systems Inc. MP2331CGTL-Z

Overview

MP2331CGTL-Z from Monolithic Power Systems is a fully integrated 24V-input, 2A synchronous step-down DC/DC converter with constant-on-time (COT) control, forced continuous conduction mode (FCCM), power-good (PG) output, and programmable soft-start. It delivers tight regulation across 4.2–24V input and 0.8–13V output ranges, features 110mΩ/45mΩ internal MOSFETs, and operates at 650kHz in a 1.6×2.1mm SOT583 package-used in compact power rails for game consoles and flat-panel displays.

For engineers reviewing the MP2331CGTL-Z datasheet, MP2331CGTL-Z pinout, MP2331CGTL-Z application, or MP2331CGTL-Z equivalent, key selection criteria include its 200µA quiescent current, pre-bias start-up capability, hiccup-mode over-current protection, thermal shutdown at 150°C, and PG open-drain signaling with 87–97% VREF rising threshold.

Technical Context

The MP2331CGTL-Z implements COT control with fixed on-time determined by input and output voltage to maintain stable 650kHz switching across wide VIN range. Its internal high-side (110mΩ) and low-side (45mΩ) N-channel MOSFETs enable synchronous rectification, eliminating external diode losses and supporting FCCM operation down to zero load.

It integrates bootstrap charging for the high-side gate driver, uses valley-current sensing for OCP, and employs an internal 7.3µA soft-start current source to charge an external capacitor-enabling monotonic startup into pre-biased outputs while preventing inrush. The PG pin asserts high only after soft-start completion and sustained VFB within 87–120% of 805mV reference.

Key Specifications

Pinout & Package

The MP2331CGTL-Z is housed in a thermally enhanced 8-pin SOT583 package (1.6mm × 2.1mm, 0.5mm pitch), with exposed thermal pad connected to GND for improved heat dissipation in space-constrained layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous buck converter applications.

Compared with MP2331GTL-Z, the MP2331CGTL-Z adds extended temperature qualification critical for automotive infotainment and industrial HMIs; versus RT7295BGJ8F, it delivers superior light-load regulation and built-in system monitoring via PG-reducing design complexity and component count.

Availability

MP2331CGTL-Z is available at Aetrix Electronics and suitable for game console power management, digital set-top box SoC supplies, and flat-panel display logic rails requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for MP2331CGTL-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, and global manufacturing partnerships.

The MP2331C product line targets space-constrained, high-efficiency DC/DC conversion in consumer electronics and industrial displays-emphasizing integration, thermal robustness, and ease of layout with minimal external components.

FAQ

What is the minimum recommended output capacitance for stable operation at 2A load?

The MP2331CGTL-Z requires ≥22µF total output capacitance with low ESR (e.g., X5R/X7R ceramic). For 3.3V/2A operation, 44µF is recommended per typical application circuit-ensuring <20mV ripple and adequate phase margin. Exceeding 220µF may delay soft-start completion due to C_{O_MAX} limit.

Can the MP2331CGTL-Z operate with a 3.3V input supply?

No. The absolute minimum input voltage is 4.2V per datasheet specifications. At 3.3V, the internal regulator fails to power control circuitry, causing UVLO lockout and no switching activity. For sub-4.2V inputs, consider the MP2307 (3V–6V range) or MP2317 (2.5V–6V).

How is the soft-start time calculated for a given capacitor value?

Soft-start time is determined by T_SS(ms) = 2 × C_SS(nF) / I_SS(µA), where I_SS = 7.3µA typical. For example, a 100nF capacitor yields ~27.4ms ramp time. This formula assumes ideal conditions; actual time may vary ±15% due to process variation and temperature drift.

Does the PG pin require an external pull-up resistor, and what value is recommended?

Yes-PG is open-drain and requires an external pull-up. A 10kΩ resistor to 3.3V or 5V is standard; values from 4.7kΩ to 100kΩ are acceptable. Lower values improve noise immunity but increase static current; higher values reduce current but risk slow rise time in noisy environments.

What is the maximum allowable inductor DCR for stable 2A operation?

Inductor DCR must be ≤19.5mΩ for 3.3V/2A operation per typical efficiency curves. Higher DCR increases conduction loss and reduces efficiency-e.g., 30mΩ DCR drops efficiency by ~2.5% at full load. Use shielded power inductors with saturation current ≥2.8A to avoid collapse under peak load.

Is the MP2331CGTL-Z pin-compatible with earlier MP2331 variants?

Yes-MP2331CGTL-Z shares identical pinout, footprint, and electrical behavior with MP2331GTL-Z and MP2331DJL-Z. However, the 'C' grade offers extended temperature range (-40°C to +125°C) and tighter V_REF tolerance (±2%), making it a drop-in upgrade for thermal-critical designs.

How does the MP2331CGTL-Z handle output short-circuit conditions?

Upon short-circuit detection, it enters hiccup mode: disables switching, discharges SS capacitor, waits ~20ms, then attempts soft-start again. Each hiccup cycle limits average power to <150mW, preventing thermal damage. Recovery occurs automatically once short is removed and V_OUT rises above 87% V_REF.