Monolithic Power Systems Inc. MP6536DU-LF-P

Overview

MP6536DU-LF-P from Monolithic Power Systems is a 3-channel half-bridge driver IC designed to control external N-channel MOSFETs in 3-phase brushless DC motor systems. It delivers ±5.5A peak output current per channel, supports 5V–26V VSP supply, operates up to 1MHz PWM frequency, and integrates 0.14Ω protected power switches with 10ns dead time. Used in compact BLDC motor drives requiring integrated fault protection and bootstrap gate drive.

For engineers reviewing the MP6536DU-LF-P datasheet, MP6536DU-LF-P pinout, MP6536DU-LF-P application, or MP6536DU-LF-P equivalent, key selection criteria include verified 3-phase half-bridge timing coordination, validated thermal shutdown at 160°C, confirmed open-drain FAULTB/FLT2B/FLT3B fault signaling, and QFN-40 (5mm×5mm) package compatibility with high-density PCB layouts.

Technical Context

The MP6536DU-LF-P implements three independent half-bridge channels, each with dedicated bootstrap supplies (BST1/BST2/BST3), low-side source terminals (LS1/LS2/LS3), and gate drive bypass rails (VDR1/VDR2). All channels accept standard 0.8V–1.8V logic-level PWM inputs and enforce symmetrical 10ns dead time to prevent shoot-through.

It integrates dual UVLO monitoring (VSP and BST), cycle-by-cycle current limiting at 5.5A per switch, thermal shutdown at 160°C with 35°C hysteresis, and fault reporting via active-low open-drain outputs (FAULTB, FLT2B, FLT3B) with distinct OCP/OTP/UVP encoding per Table 1 of the datasheet.

Key Specifications

Pinout & Package

MP6536DU-LF-P is housed in a thermally enhanced 40-pin QFN package (5mm × 5mm, 0.5mm pitch) with exposed thermal pad. Pin numbering follows top-view orientation with Pin 1 marked by index area; PGND pins (22,23, and others) connect directly to the exposed pad for optimal heat dissipation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 3-channel half-bridge driver applications.

Compared with DRV8305PWP and STSPIN32F0A, MP6536DU-LF-P offers minimal-footprint, logic-input-only operation with best-in-class 10ns dead time and triple fault flag decoding-ideal for cost-sensitive, high-volume BLDC systems where MCU handles all intelligence externally.

Availability

MP6536DU-LF-P is available at Aetrix Electronics and suitable for BLDC motor fan control, industrial pump drivers, electric power tool modules, and medical ventilator motor systems requiring stable component supply and RoHS-compliant packaging.

Supply support for MP6536DU-LF-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 manufacturing partners qualified to ISO 9001 and IATF 16949 standards.

The MP6536 belongs to MPS's high-current gate driver product line, engineered specifically for compact, thermally constrained 3-phase BLDC motor applications where reliability under overload and fast fault response are critical.

FAQ

What is the minimum recommended bootstrap capacitor value for BST1/BST2/BST3?

The datasheet specifies a minimum of 0.1µF ceramic capacitor between each BSTx and SWx node. This value ensures sufficient charge storage to sustain high-side gate drive during continuous PWM operation at 1MHz. Larger values (e.g., 0.22µF) improve stability under high-duty-cycle conditions but do not alter functional behavior.

Can MP6536DU-LF-P drive P-channel high-side MOSFETs?

No. The MP6536DU-LF-P is designed exclusively for N-channel high-side MOSFETs using bootstrap gate drive. Its BSTx outputs are floating supplies referenced to SWx, which only support gate-source voltage generation for N-channel devices. Driving P-channel devices would require inverted logic and non-bootstrap topology.

How does the FAULTB signal behave during thermal shutdown?

FAULTB asserts low during thermal shutdown (T_J ≥ 160°C) and remains low until junction temperature falls below 125°C (35°C hysteresis). During this period, all SWx outputs enter high-impedance state. FAULTB returns high automatically upon thermal recovery-no external reset is required.

Is STBYB compatible with direct MCU GPIO control without pull-up resistors?

Yes. STBYB has an internal pull-down resistor, so it defaults to low (high-impedance output mode) when left unconnected. Driving it high with a standard 3.3V or 5V GPIO meets its 1.6V–1.8V logic-high threshold and requires no external pull-up.

What is the purpose of separate VDR1 and VDR2 pins?

VDR1 powers gate drive circuitry for SW1 and SW2 channels; VDR2 powers SW3's gate drive. This separation isolates noise and transient coupling between phases, improving commutation timing accuracy and reducing crosstalk-induced jitter in multi-phase BLDC systems.

Does MP6536DU-LF-P support 100% duty cycle operation?

No. Due to bootstrap architecture, sustained 100% high-side conduction is not supported. The high-side MOSFET requires periodic low-side conduction to recharge the BSTx capacitor. For continuous conduction, an external charge pump or high-side driver with floating supply is required.

How are FLT2B and FLT3B encoded for simultaneous faults?

FLT2B and FLT3B follow the truth table in datasheet page 10: both go low only during over-current (OCP); FLT2B low + FLT3B high indicates over-temperature (OTP); FLT2B high + FLT3B low indicates under-voltage (UVP). Simultaneous OCP+OTP results in both low, matching the OCP row.