Monolithic Power Systems Inc. MP6615GQKT-Z

Overview

MP6615GQKT-Z from Monolithic Power Systems is a 40V, 8A H-bridge DC motor driver IC integrating four N-channel power MOSFETs (11mΩ R_DS(ON) each at 25°C), internal charge pump for 100% duty-cycle high-side drive, bidirectional current-sense amplifiers (1/11000 A/A typical ratio), and protection circuitry including UVLO (4.4V), OVP (48V), thermal shutdown (150°C), and configurable over-current protection. It drives brushed DC motors in automotive seat actuators and industrial door locks.

For engineers reviewing the MP6615GQKT-Z datasheet, MP6615GQKT-Z pinout, MP6615GQKT-Z application, or MP6615GQKT-Z equivalent, this page delivers verified technical context, validated pin functions, real-world use cases, and confirmed alternative parts - all grounded in the official MPS Rev. 1.0 datasheet and functional block diagram.

Technical Context

The MP6615 implements a fully integrated H-bridge with independent gate drivers, an internal charge pump generating V_CP ≈ VIN + 5V to sustain high-side FET conduction at 100% duty cycle, and a trickle-charge circuit maintaining gate voltage under sustained PWM. Its dual current-sense outputs (SOA/SOB) deliver proportional analog currents referenced to VREF, enabling precise motor current monitoring without external shunts.

Three input logic modes-EN/PWM, ENBL/DIR/BRK, and INH/INL-are selected via INM[1:0], allowing flexible microcontroller interface options. Fault handling includes open-drain nFAULT assertion on OCP (16–25A threshold), thermal shutdown, and UVLO/OVP events, with OCMD pin selecting latch-off vs. auto-retry OCP behavior.

Key Specifications

Pinout & Package

TQFN-26 (6mm × 6mm) package with exposed thermal pad; requires soldering to PCB ground plane for thermal management and electrical stability.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar H-bridge motor driver applications.

Compared with TB9051FTG and VNH7040AS, MP6615GQKT-Z uniquely combines 8A continuous drive, on-chip current sensing, 100%-duty-cycle support, and three hardware-selectable control modes - making it optimal for space-constrained, thermally demanding brushed motor applications requiring minimal external components.

Availability

MP6615GQKT-Z is available at Aetrix Electronics and suitable for automotive seat actuators, industrial door locks, robotics joint control, and medical pump actuation requiring stable component supply across production lifecycles.

Supply support for MP6615GQKT-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 power management ICs, with emphasis on integration, efficiency, and thermal robustness.

The MP6615 belongs to MPS's motor driver product line, designed specifically for compact, high-current brushed DC motor control in automotive and industrial environments where reliability, current sensing, and fault resilience are critical.

FAQ

What is the maximum continuous output current of the MP6615GQKT-Z?

The MP6615GQKT-Z delivers up to 8A of continuous output current under typical thermal conditions (T_A = 25°C, 4-layer PCB with adequate copper pour and thermal vias). This rating assumes proper layout per MPS AN-112 guidelines and accounts for 11mΩ R_DS(ON) per MOSFET and internal thermal shutdown at 150°C.

How does the MP6615GQKT-Z support 100% duty cycle operation?

It uses an internal charge pump with CP1/CP2/VCP capacitors to generate a gate drive voltage exceeding VIN, enabling sustained conduction of high-side N-channel MOSFETs. A trickle-charge circuit maintains sufficient V_CP even during extended high-side-on periods, eliminating shoot-through risk and ensuring full forward torque capability.

Can the MP6615GQKT-Z sense current in both motor directions?

Yes - the internal current-sense amplifiers monitor low-side FET current in both forward and reverse conduction paths. SOA and SOB provide proportional output currents (e.g., I_LOAD/11000) that swing above or below V_REF, enabling bidirectional current measurement without polarity reversal or external circuitry.

What are the key differences between latch-off and retry OCP modes?

When OCMD is tied to GND, OCP triggers permanent latch-off until VIN drops below UVLO. When OCMD is left open or pulled high, the device disables outputs for ~2ms then automatically re-enables - useful for transient overload recovery. Both modes assert nFAULT low, but only retry mode permits autonomous resumption.

Which external capacitors are mandatory for stable operation?

Four are required: (1) 4.7–10µF X7R ceramic from VG to GND; (2) 1µF/10V X7R from VCP to VIN; (3) 100nF/≥VIN-rated X7R between CP1 and CP2; and (4) bulk input capacitance (not specified in datasheet but recommended ≥10µF) at VIN–PGND. All must be placed adjacent to respective pins per layout Figure 4.

Does the MP6615GQKT-Z require external bootstrap diodes or capacitors?

No - the integrated charge pump eliminates need for external bootstrap components. Unlike traditional high-side drivers, MP6615 uses a flying-capacitor topology (CP1/CP2/VCP) to generate gate voltage, removing diode forward-drop limitations and enabling true 100% duty cycle without timing constraints.

How is thermal performance affected by PCB layout?

Thermal resistance θ_JA is specified at 21.4°C/W on a JESD51-7 4-layer board. Performance degrades significantly without the exposed thermal pad soldered to a large GND plane and thermal vias. Layout deviations (e.g., missing vias, undersized copper) can raise junction temperature >30°C at 8A, risking thermal shutdown.