Monolithic Power Systems Inc. MP2102DK-LF-Z

Overview

MP2102DK-LF-Z from Monolithic Power Systems is a dual-output, synchronous step-down DC-DC converter with integrated high-side and synchronous rectifier MOSFETs, delivering up to 800mA per channel from 2.5V–6V input. It operates at fixed 1.5MHz PWM frequency, regulates outputs down to 0.6V, and features cycle-by-cycle current limiting and thermal shutdown. It powers dual-rail subsystems in Li+-battery-powered portable instruments.

For engineers reviewing the MP2102DK-LF-Z datasheet, MP2102DK-LF-Z pinout, MP2102DK-LF-Z application, or MP2102DK-LF-Z equivalent, this page provides verified functional identity, confirmed MSOP-10 package mapping, validated 10-pin terminal roles, real-world efficiency curves (up to 95%), and direct alternatives with documented electrical and application-level differences.

Technical Context

The MP2102DK-LF-Z implements peak current-mode control with internal slope compensation for stable operation at duty cycles >50%, eliminating external compensation components. Each channel uses independent enable inputs (EN1/EN2) and feedback pins (FB1/FB2) to support asynchronous start-up and independent output regulation.

Its open-drain PWROK output asserts low when either regulated output deviates beyond ±10% of target, while the DLY pin enables programmable power-on reset delay via external capacitor (e.g., 1nF → 0.5ms). The device integrates both P-channel main switches and N-channel synchronous rectifiers, removing need for external Schottky diodes.

Key Specifications

Pinout & Package

MP2102DK-LF-Z is housed in a RoHS-compliant, lead-free 10-pin MSOP package (3.0mm × 4.9mm), with exposed thermal pad omitted (unlike QFN variant); suitable for standard reflow assembly and moderate-power thermal management.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-output synchronous step-down converter applications.

Compared with MP2102DQ-LF-Z, the MSOP variant trades thermal performance for ease of hand-soldering and legacy board compatibility; versus TPS65120RGTR, it delivers true dual independent regulation with sequencing control-making it essential for systems requiring strict rail-ordering or fault-isolated power domains.

Availability

MP2102DK-LF-Z is available at Aetrix Electronics and suitable for DVD+/-RW drives, smart phones, PDAs, and digital cameras requiring stable component supply across extended production lifecycles and battery-operated reliability benchmarks.

Supply support for MP2102DK-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 in the US, China, and Taiwan, and global distribution since 1997.

The MP2102 belongs to MPS's high-frequency synchronous buck converter product line, engineered specifically for space-constrained, battery-powered portable electronics demanding dual-rail efficiency, minimal external components, and robust protection features.

FAQ

What is the maximum achievable output voltage for each channel?

The MP2102DK-LF-Z supports output voltages from 0.6V to 5.4V, set by external resistor dividers on FB1/FB2. Due to its ~90% maximum duty cycle and internal MOSFET R_DS(on), the practical upper limit is approximately 90% of VIN minus IR drops-e.g., 5.4V output requires ≥6V input. The 5.4V ceiling is guaranteed across temperature and load per datasheet specifications.

Can EN1 and EN2 be tied together for simultaneous channel enable?

Yes-EN1 and EN2 may be connected to a common enable signal for synchronized startup. Each pin has an internal 800kΩ pull-down resistor, so no external components are needed. However, independent control is supported if sequencing (e.g., core before I/O) is required, and both pins tolerate 0–6.5V logic levels.

Is the PWROK output truly open-drain, and what pull-up voltage should be used?

Yes, PWROK is a true open-drain NMOS output. It must be pulled up externally-typically to the host system's logic rail (e.g., 1.8V or 3.3V)-with a resistor between 10kΩ and 100kΩ. The datasheet specifies a 5mA sink capability and 0.3V low-level threshold, ensuring compatibility with standard CMOS inputs.

How does the DLY pin affect system boot timing, and what capacitor value gives 2ms delay?

The DLY pin sets PWROK assertion delay using t_DELAY ≈ 500µs × C₄(nF). For 2ms, use a 4nF capacitor (e.g., 3.9nF standard value). This delay ensures downstream logic (e.g., FPGA configuration or memory initialization) completes before PWROK signals "power good," preventing race conditions during cold start.

What is the recommended inductor DCR for optimal efficiency at 800mA load?

MPS recommends inductor DCR <200mΩ for best efficiency at full 800mA load. Lower DCR reduces conduction loss-e.g., Coilcraft LP1704-222M (2.2µH, 70mΩ DCR, 1.7A saturation) achieves >93% efficiency at 3.6V→1.8V/800mA per channel, per typical performance curves in the datasheet.

Does the MP2102DK-LF-Z support forced PWM mode or only auto PFM/PWM?

The MP2102DK-LF-Z operates exclusively in fixed-frequency PWM mode at 1.5MHz under all load conditions-no PFM or burst-mode operation. This ensures constant switching frequency for predictable EMI filtering and eliminates low-load output voltage ripple associated with discontinuous conduction mode.

What is the thermal resistance (θ_JA) of the MSOP-10 package, and how does it impact 800mA operation?

The MSOP-10 package has θ_JA = 150°C/W. At 800mA per channel with 3.6V input and 1.8V output, power dissipation is ~0.4W per channel. In 70°C ambient, junction temperature rises ~60°C-well below the 150°C shutdown threshold. Adequate copper area (≥1 sq-in) is still required to maintain reliability over lifetime.