Monolithic Power Systems Inc. MP18021HN-A-LF-Z

Overview

MP18021HN-A-LF-Z from Monolithic Power Systems is a 100V, 2.5A high-frequency half-bridge N-channel MOSFET gate driver in SOIC8E package, featuring independent high-side and low-side control with <5ns propagation matching, integrated bootstrap diode, and dual UVLO protection. It drives 1nF loads with 12ns/9ns rise/fall times at 12V VDD and supports telecom half-bridge power supplies.

For engineers reviewing the MP18021HN-A-LF-Z datasheet, MP18021HN-A-LF-Z pinout, MP18021HN-A-LF-Z application, or MP18021HN-A-LF-Z equivalent, key selection criteria include bootstrap voltage range (100V), gate drive matching (<5ns), TTL-compatible inputs, quiescent current (<150µA), and SOIC8E thermal performance (θJA = 48°C/W).

Technical Context

The MP18021HN-A-LF-Z implements a level-shifted floating driver architecture with independent INH/INL inputs controlling DRVH and DRVL outputs. Its internal bootstrap diode enables self-biased high-side operation up to 100V VBST–SW, while matched propagation delays (16ns typ.) and sub-5ns channel-to-channel skew ensure precise timing in hard-switching topologies.

Dual under-voltage lockout circuits monitor both VDD (7.7–8.5V threshold) and BST–SW (6.7–7.5V threshold), forcing DRVH and DRVL low during supply faults. The device operates across –40°C to +125°C junction temperature with thermal shutdown at 160°C and 20°C hysteresis.

Key Specifications

Pinout & Package

MP18021HN-A-LF-Z uses the SOIC8E package (JEDEC MS-012 BA), with exposed thermal pad connected to VSS for enhanced heat dissipation. Package dimensions: 4.90 × 6.00 × 1.75 mm, θJA = 48°C/W on 4-layer PCB.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar half-bridge gate driver applications.

Compared with IRS21844STRPBF and LM5109BMAX/NOPB, MP18021HN-A-LF-Z delivers superior timing precision (<5ns matching), lower quiescent current (<150µA), and integrated thermal management via SOIC8E exposed pad-making it optimal for high-density, high-frequency telecom and avionics power stages.

Availability

MP18021HN-A-LF-Z is available at Aetrix Electronics and suitable for telecom half-bridge power supplies, avionics DC-DC converters, and two-switch forward converters requiring stable component supply, RoHS-compliant packaging, and long-term lifecycle assurance.

Supply support for MP18021HN-A-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 manufacturing partnerships.

The MP18021 series targets high-frequency isolated and non-isolated DC-DC conversion, emphasizing timing accuracy, integrated bootstrap functionality, and thermal robustness for mission-critical power systems.

FAQ

What is the maximum recommended switching frequency for MP18021HN-A-LF-Z?

The device supports reliable operation up to 2MHz, based on its 16ns typical propagation delay and 12ns/9ns rise/fall times into 1nF loads. At 500kHz, total gate drive current is 3.5mA (IDDO), well within SOIC8E thermal limits. Higher frequencies require careful PCB layout to minimize parasitic inductance on BST and SW nodes.

Can MP18021HN-A-LF-Z drive GaN HEMTs?

Yes-it delivers 2.5A peak source/sink current and 12ns/9ns edge rates suitable for common GaN devices with Qg < 10nC. However, its 100V VBST rating and lack of negative turn-off bias mean it's best paired with enhancement-mode GaN FETs requiring only positive gate drive, not depletion-mode types needing negative voltage.

How does the integrated bootstrap diode affect reliability in high-temperature operation?

The on-chip diode has VF = 0.9V @ 100mA and dynamic resistance of 2.5Ω, resulting in <90mW conduction loss at 100mA. This is significantly lower than typical 1N4148 losses, reducing thermal stress on the die. Combined with SOIC8E's exposed pad, it maintains <125°C junction temperature even at TA = 100°C in 500kHz operation.

Is there a minimum required bootstrap capacitor value for 100V operation?

For 100V VSW and 500kHz operation, a 100nF X7R ceramic capacitor rated ≥100V is recommended. This ensures <1% voltage droop per cycle (calculated from IBSTO = 3mA and tON ≈ 1µs), maintaining sufficient gate drive margin above the 6.7V BST–SW UVLO threshold during extended high-side conduction.

Does MP18021HN-A-LF-Z support 3.3V logic inputs?

No-its INH/INL inputs require TTL-level thresholds: VIH ≥ 2.4V and VIL ≤ 1.4V. A 3.3V microcontroller GPIO can drive it directly, but 1.8V or 2.5V logic sources require level-shifting. The internal 185kΩ pull-down ensures safe default-low state if inputs float.

What failure modes does the dual UVLO protect against?

Dual UVLO prevents false turn-on during startup, brown-out, or bootstrap capacitor discharge. If VDD drops below 7.7V, DRVL is forced low; if BST–SW falls below 6.7V, DRVH is forced low-eliminating shoot-through risk in half-bridge configurations where high-side and low-side FETs could conduct simultaneously.

How is thermal performance affected by the SOIC8E exposed pad connection?

Connecting the exposed pad to a ≥1cm² copper pour reduces θJA from 48°C/W to ~35°C/W. Without this connection, power dissipation is limited to 0.52W at TA = 100°C; with proper thermal land pattern and soldering, it supports 0.75W-enabling full 2.5A drive capability at elevated ambient temperatures.