Monolithic Power Systems Inc. MP9517GJL-P

Overview

MP9517GJL-P from Monolithic Power Systems is a single-phase brushless DC motor driver IC with integrated Hall-effect sensor, power MOSFETs, and full protection circuitry. It operates from 3.3V to 18V input, delivers up to 2A output current limit, features fixed 26kHz switching frequency, soft-on/off commutation (22.5°/45°), and open-drain FG speed indicator - designed for compact, low-noise CPU fan control in servers and desktop PCs.

For engineers reviewing the MP9517GJL-P datasheet, MP9517GJL-P pinout, MP9517GJL-P application, or MP9517GJL-P equivalent, key selection criteria include Hall-integrated single-phase BLDC topology, TSOT23-6-L package compatibility, reverse voltage protection, rotor deadlock recovery timing (0.6s detection), and PWM-controlled speed regulation across 2–100kHz input range.

Technical Context

The MP9517GJL-P implements a Hall-sensor-based commutation engine that synchronizes winding BEMF and current zero-crossing within the same phase, enabling precise single-phase BLDC rotation without external sensors. Its internal half-bridge integrates N-channel HS/LS MOSFETs with combined R_DS(on) of 1.02Ω and supports automatic soft-switching transitions.

Control logic accepts PWM input (2–100kHz) with internal 50kΩ pull-up and interprets duty cycle to linearly modulate output drive; FG provides open-drain Hall-edge pulses at motor speed. Protection includes UVLO (3.25V rising), OVP (19V), thermal shutdown (150°C), and rotor lock detection with 3.6s auto-recovery.

Key Specifications

Pinout & Package

MP9517GJL-P is housed in a TSOT23-6-L package - ultra-compact, surface-mount, lead-free, RoHS-compliant 6-pin thermally enhanced variant with exposed pad (not electrically connected). Pin 1 is lower-left when top marking "BMG" is read left-to-right.

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 DRV10970PWP, MP9517GJL-P uniquely combines Hall integration, TSOT23-6-L footprint, and single-phase optimization - delivering lowest system-level cost and smallest PCB area for CPU/server fan applications.

Availability

MP9517GJL-P is available at Aetrix Electronics and suitable for CPU fan control, server chassis cooling, embedded industrial fan, and network equipment cooling applications requiring stable component supply, long-lifecycle support, and RoHS-compliant sourcing.

Supply support for MP9517GJL-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 power management ICs, including DC/DC converters, motor drivers, and LED controllers - headquartered in Kirkland, WA, with global design and support centers.

The MP9517 product line targets compact, intelligent fan control solutions for computing and communications infrastructure - emphasizing integration, reliability, and acoustic performance in space-constrained thermal systems.

FAQ

What is the minimum PWM duty cycle required to start motor rotation?

The MP9517GJL-P requires ≥9% PWM duty cycle to initiate rotation, with 1.2% hysteresis to prevent oscillation near threshold. Below 7.8%, the motor remains stationary. This start-up behavior is internally fixed and not adjustable via external components or registers.

Does MP9517GJL-P support bidirectional motor control?

No. MP9517GJL-P is a unidirectional single-phase BLDC driver. Its internal commutation logic and Hall sensor orientation are fixed for clockwise-only rotation. Reverse operation would require hardware redesign and is not supported by the IC's architecture or protection schemes.

How is the FG output frequency related to motor speed?

FG outputs one pulse per Hall sensor edge transition. For a standard 2-pole BLDC motor, FG frequency equals RPM ÷ 60. For example, at 6000 RPM, FG outputs 100 Hz. The signal is open-drain and requires an external pull-up resistor (typically 4.7kΩ to 5V).

What thermal derating applies above 25°C ambient?

With θ_JA = 100°C/W (TSOT23-6), power dissipation must be reduced by 12.5mW/°C above 25°C to maintain T_J ≤ 125°C. At 85°C ambient, maximum continuous power drops to 0.75W - requiring careful PCB copper area and airflow validation.

Can MP9517GJL-P drive motors beyond 2A peak current?

No. The overload current limit is fixed at ~2A (typical). Exceeding this triggers immediate HS-FET shutdown with 1.5µs blanking time. Sustained operation above 2A risks thermal shutdown or permanent damage - motor selection must stay within rated limits.

Is the Hall sensor sensitivity adjustable?

No. Hall sensor sensitivity is factory-trimmed and fixed at ±1mT minimum magnetic field strength. No external pins, registers, or passive components allow adjustment. Motor magnet strength and air gap must comply with datasheet mechanical recommendations.

What is the purpose of the 2Ω resistor (R1) in the typical application circuit?

R1 forms an RC snubber with the input capacitor (C1) to dampen ringing caused by energy exchange during soft commutation. It suppresses high-frequency voltage spikes on VCC, reducing EMI and preventing false OVP triggering - especially critical with large inertia fans.