Monolithic Power Systems Inc. MP2158AGQH-P

Overview

MP2158AGQH-P from Monolithic Power Systems is a synchronous step-down DC-DC converter IC with integrated 120mΩ high-side and 90mΩ low-side MOSFETs, delivering up to 1A continuous output current from a 2.5V–6V input. It features constant-on-time (COT) control, 17μA quiescent current, 1.5MHz switching frequency, and 0.6V reference voltage for adjustable output down to 0.6V - optimized for space-constrained portable power rails in FPGAs and DSPs.

For engineers reviewing the MP2158AGQH-P datasheet, MP2158AGQH-P pinout, MP2158AGQH-P application, or MP2158AGQH-P equivalent, key selection criteria include its ultra-low IQ for battery longevity, ±1.5% VFB accuracy for tight regulation, EN/PG support for sequencing in multi-rail systems, and QFN-8 (1.5mm×2mm) package compatibility with high-density PCB layouts.

Technical Context

The MP2158AGQH-P implements a constant-on-time control architecture with input-voltage feed-forward, enabling near-constant 1.5MHz switching across input (2.5–6V) and output (0.6–VIN) ranges while delivering fast transient response without external compensation. Its COT loop uses an internal 0.6V reference and monitors FB voltage against ±10% PG thresholds.

It integrates cycle-by-cycle over-current protection with 2A minimum current limit, hiccup-mode short-circuit recovery, thermal shutdown at 150°C, and 100% duty-cycle operation in dropout - all managed within a single monolithic die using proprietary light-load DCM control that disables reverse inductor current via zero-cross detection.

Key Specifications

Pinout & Package

MP2158AGQH-P is housed in an ultra-small QFN-8 package measuring 1.5mm × 2.0mm with exposed thermal pad, optimized for thermal performance and board area savings in portable designs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS62865RRLR and RT7295BGJ6F, MP2158AGQH-P uniquely balances 1A output, full adjustability (0.6V–VIN), EN/PG sequencing support, and ultra-small footprint - making it optimal for multi-rail portable systems requiring design flexibility and long battery life.

Availability

MP2158AGQH-P is available at Aetrix Electronics and suitable for wireless networking cards, portable medical instruments, and battery-powered test equipment requiring stable component supply with guaranteed long-term manufacturability.

Supply support for MP2158AGQH-P 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 manufacturing partnerships.

The MP2158A belongs to MPS's ultra-compact DC-DC converter product line, engineered specifically for space- and power-constrained portable electronics requiring high efficiency, fast transient response, and minimal external components.

FAQ

What is the minimum recommended output capacitance for stable operation?

The MP2158AGQH-P is stable with low-ESR ceramic capacitors ≥10μF. Using X5R/X7R dielectrics with 10μF at the output ensures <15mV peak-to-peak ripple at 1A load and 1.2V output, meeting typical FPGA core rail requirements without additional compensation.

Does MP2158AGQH-P support 100% duty-cycle operation?

Yes - the device supports 100% duty-cycle operation in dropout mode, allowing VOUT to track VIN down to VOUT = VIN − (ILOAD × RDSON_HS). This enables seamless transition during brownout conditions without output collapse, critical for maintaining MCU operation during battery voltage sag.

How does the power good (PG) pin behave during startup and fault conditions?

PG asserts high (pulled to VIN via 550kΩ internal resistor) only when FB voltage remains within ±10% of 0.6V for ≥50μs. During startup, PG remains low until VOUT settles; during over-current or thermal shutdown, PG pulls low within 50μs, providing deterministic system reset signaling.

Can MP2158AGQH-P operate with input voltages below 2.5V?

No - the absolute minimum operating input is 2.5V per datasheet specifications. Below this, UVLO prevents enablement; the rising UVLO threshold is 2.3V typical with 260mV hysteresis, ensuring reliable turn-on only within the validated 2.5–6V range.

What is the thermal performance of the QFN-8 (1.5mm×2mm) package?

With JEDEC-standard 4-layer PCB layout, the package exhibits θJA = 110°C/W and θJC = 55°C/W. At 1A load and 5V input, junction temperature rise is ~65°C above ambient - well within the 125°C max operating TJ, provided the exposed thermal pad is soldered to ≥100mm² copper pour.

Is external compensation required for loop stability?

No - the constant-on-time control architecture eliminates the need for external compensation components. Stability is ensured across all valid input/output combinations using only the recommended 10μF input and output ceramic capacitors and a 1μH inductor.

How does light-load efficiency compare between CCM and DCM modes?

At 10mA load, DCM operation improves efficiency by 18% versus forced CCM (e.g., 82% vs 64%) due to elimination of reverse inductor current and reduced switching losses - enabled automatically via zero-current detection without user configuration.