Monolithic Power Systems Inc. MP20046DQ-S-LF-Z

Overview

MP20046DQ-S-LF-Z from Monolithic Power Systems is a fast-transient-response, 2A low-dropout linear regulator with fixed 3.3V output, 210mV dropout at 2A, 70dB PSRR at 100Hz, and open-drain power-good (PG) output-designed for FPGA and DSP core supplies in telecom and server applications.

For engineers reviewing the MP20046DQ-S-LF-Z datasheet, MP20046DQ-S-LF-Z pinout, MP20046DQ-S-LF-Z application, or MP20046DQ-S-LF-Z equivalent, key selection criteria include dropout voltage under full load, PG threshold accuracy, thermal resistance in QFN10 package, and compatibility with low-ESR ceramic output capacitors.

Technical Context

The MP20046DQ-S-LF-Z uses an internal PMOS pass element to achieve low dropout and ultra-low ground current (75μA at 2A, 1μA in shutdown), enabling high-efficiency operation in battery-sensitive and thermally constrained systems. Its control loop architecture delivers fast load- and line-transient response without external compensation.

Integrated functions include precision 83% VOUT trip threshold for PG assertion, thermal shutdown at +150°C with 20°C hysteresis, and current limiting at 3.3A (min). The device operates across 2.7V–5.5V input and requires only 47μF ceramic output capacitance with ESR <1.5Ω.

Key Specifications

Pinout & Package

MP20046DQ-S-LF-Z is housed in a thermally enhanced 10-pin QFN package (3mm × 3mm, exposed pad), optimized for PCB heat dissipation with θJA = 60°C/W and θJC = 12°C/W on a 4-layer board.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LDO regulator applications.

Compared with TPS7A4700RGWR and ADM7172ACPZ-R7, MP20046DQ-S-LF-Z uniquely combines integrated PG, 75μA full-load quiescent current, and QFN10 compactness-making it optimal for space-constrained, cost-sensitive FPGA/DSP designs requiring autonomous power sequencing.

Availability

MP20046DQ-S-LF-Z is available at Aetrix Electronics and suitable for telecom infrastructure, server power management, and FPGA-based embedded computing requiring stable component supply, RoHS-compliant packaging, and tape-and-reel delivery.

Supply support for MP20046DQ-S-LF-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 across Asia and North America.

The MP20046 belongs to MPS's fast-transient LDO product line, engineered specifically for powering noise-sensitive digital loads-including FPGAs, DSPs, and ASICs-in telecom, datacenter, and portable equipment where efficiency, size, and reliability are critical.

FAQ

What is the minimum input voltage required for MP20046DQ-S-LF-Z to regulate 3.3V output?

The absolute minimum input voltage is 3.51V, calculated from the 210mV dropout specification at 2A load (3.3V + 0.21V). However, the recommended operating range starts at 2.7V input-valid only for lower output voltages (e.g., 1.5V); for 3.3V output, stable regulation requires VIN ≥ 3.51V per datasheet Section 6 Absolute Maximum Ratings and Electrical Characteristics.

Can MP20046DQ-S-LF-Z operate without an external pull-up resistor on the PG pin?

No. The PG pin is an open-drain output and requires an external pull-up resistor to a valid logic-high voltage (e.g., 3.3V or 5V) to assert HIGH when VOUT is within regulation. Without pull-up, PG remains floating and cannot drive downstream reset logic-this is explicitly required in the Operation section (page 11) and Typical Application schematic (page 2).

Is the SENSE pin mandatory for proper operation?

Yes. The SENSE pin must be connected directly to the load-side of the output capacitor to enable remote voltage sensing. Omitting this connection degrades output voltage accuracy to ±3% (vs. ±1%) due to PCB trace IR drop, as confirmed in the Application Information section (page 12) and Pin Functions table (page 5).

What thermal derating applies when using MP20046DQ-S-LF-Z in still-air conditions?

At TA = +25°C on a standard 4-layer JEDEC board, maximum continuous power dissipation is 1.67W (θJA = 60°C/W). For every 1°C rise in ambient temperature, allowable power drops by 27.8mW. At +70°C ambient, max dissipation reduces to 0.28W-requiring VIN–VOUT margin reduction or forced airflow to sustain 2A output.

Does MP20046DQ-S-LF-Z support reverse polarity protection?

No. The device lacks internal reverse-voltage protection. Applying reversed input voltage (VIN < GND) may damage the internal PMOS pass transistor and ESD structures. External protection-such as a series Schottky diode-is required in systems where input polarity reversal is possible.

How does the EN pin behave during power-up sequences?

The EN pin is active-low with VIH ≥1.5V and VIL ≤0.4V. During power-up, if EN is tied to VIN through a resistor divider, the device enables only after VIN exceeds ~1.5V-providing inherent input-voltage sequencing. Floating EN is prohibited; it must be pulled to GND (enabled) or driven actively (disabled) per Section 11 Operation.

What is the maximum allowable output capacitance for MP20046DQ-S-LF-Z?

No upper limit is specified-the device is stable with ceramic capacitors ≥47μF and ESR <1.5Ω. Larger values (e.g., 100μF) improve load transient response and reduce noise but increase inrush current and startup time. The datasheet confirms stability across the full range of standard X5R/X7R ceramics used in production designs.