Monolithic Power Systems Inc. MP9518GJS-XXXX-P

Overview

MP9518GJS-XXXX-P from Monolithic Power Systems is a single-phase BLDC motor driver IC with integrated Hall sensor, 3.3V–18V input range, 1.2A programmable current limit, and TSOT23-6-SL package. It drives CPU/server fans via PWM speed control, delivers FG/RD open-drain speed/fault indication, and features soft on/off phase transition and automatic BEMF–current phase lock for low-noise operation.

For engineers reviewing the MP9518GJS-XXXX-P datasheet, MP9518GJS-XXXX-P pinout, MP9518GJS-XXXX-P application, or MP9518GJS-XXXX-P equivalent, key selection criteria include integrated Hall sensing capability, reverse-voltage protection, rotor lock detection timing (0.6s), thermal shutdown threshold (150°C), and compatibility with 12–48kHz PWM input frequency.

Technical Context

The MP9518GJS-XXXX-P implements a Hall-based commutation controller with adaptive phase-lock logic that aligns winding BEMF zero-crossing with Hall signal edges. Its internal half-bridge integrates N-channel HS/LS MOSFETs (520mΩ + 330mΩ total R_DS(on)) and supports fixed 26kHz switching to avoid audible noise.

Control is executed via a 100kΩ internally pulled-up PWM input (12–48kHz), while FG/RD provides dual-mode open-drain output: rotational speed pulses (1:1 with Hall frequency) or rotor lock fault assertion after 0.6s of no Hall edge detection, followed by 3.6s auto-recovery.

Key Specifications

Pinout & Package

MP9518GJS-XXXX-P is housed in a thermally enhanced TSOT23-6-SL package (0.95mm height, JEDEC MO-193 AB variant), optimized for compact fan module layouts and PCB space-constrained server heatsink assemblies.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar single-phase BLDC motor driver applications.

Compared with MP6532GJ-Z and DRV10970RGET, MP9518GJS-XXXX-P uniquely combines integrated Hall sensing, reverse-voltage protection, and 0.6s rotor lock detection in a 0.95mm-height TSOT23-6-SL package - making it optimal for space- and noise-constrained single-phase fan applications where supply line polarity risk exists.

Availability

MP9518GJS-XXXX-P is available at Aetrix Electronics and suitable for CPU fan control in servers, embedded system cooling fans, desktop PC CPU coolers, and low-profile notebook heat sink modules requiring stable component supply across extended production lifecycles.

Supply support for MP9518GJS-XXXX-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 MP9518 belongs to MPS's fan motor driver product line, engineered specifically for intelligent, low-noise, and highly reliable thermal management in computing and communications infrastructure.

FAQ

What is the purpose of the FG/RD pin on MP9518GJS-XXXX-P?

The FG/RD pin serves dual functions: as an open-drain FG (tachometer) output delivering speed pulses synchronized to Hall sensor edges, and as an RD (rotor deadlock) fault indicator that pulls low for 0.6 seconds upon detecting no Hall edge change, followed by automatic 3.6-second recovery attempt. External pull-up resistor is mandatory for both modes.

How does the MP9518GJS-XXXX-P achieve soft on/off transitions?

It implements a 16-step linear duty-cycle ramp during startup and shutdown, controlled by configurable soft-turn-on (θSON_100 = 23.9°) and soft-turn-off (θSOFF_100 = 45°) angles. This gradual transition reduces mechanical shock, audible noise, and inrush current stress on motor windings and bearings.

Does MP9518GJS-XXXX-P require external MOSFETs?

No. The device integrates a complete N-channel half-bridge with total R_DS(on) of 850mΩ (520mΩ HS + 330mΩ LS), eliminating the need for external power switches. Only passive components - input capacitor, optional snubber, and FG/RD pull-up - are required for basic operation.

What protection features are built into MP9518GJS-XXXX-P?

It includes input over-voltage protection (19V threshold), under-voltage lockout (3V rising), thermal shutdown (150°C), rotor deadlock detection (0.6s timeout), and input reverse-voltage protection. All protections feature automatic recovery except OVP, which resumes once VCC falls below threshold.

Can MP9518GJS-XXXX-P drive bidirectional BLDC motors?

No. It is designed exclusively for unidirectional single-phase BLDC fan motors. The internal commutation logic and half-bridge topology support forward rotation only; direction reversal requires external H-bridge reconfiguration not supported by this IC.

What is the significance of the "XXXX" in MP9518GJS-XXXX-P?

The "XXXX" denotes a 4-digit hexadecimal configuration code defining operational parameters: current limit (e.g., 0001 = 1.2A), soft on/off enable, PLL disable, and FG/RD output mode. Default is 0000; custom codes must be generated in collaboration with an MPS FAE per application requirements.

Is MP9518GJS-XXXX-P RoHS-compliant and halogen-free?

Yes. All MPS parts, including MP9518GJS-XXXX-P, are lead-free, halogen-free, and fully compliant with the EU RoHS directive. Green status documentation is available on the MPS Quality Assurance webpage.