Monolithic Power Systems Inc. MP6605EGR-Z

Overview

MP6605EGR-Z from Monolithic Power Systems is a 4-channel low-side driver IC with serial interface, designed to control inductive loads such as unipolar stepper motors and solenoids. It integrates four N-channel MOSFETs (R_DS(ON) = 350 mΩ), supports 4.5V–60V input voltage, delivers up to 1.5A per channel (single-FET on), and features over-current, under-voltage lockout, and thermal shutdown protections.

For engineers reviewing the MP6605EGR-Z datasheet, MP6605EGR-Z pinout, MP6605EGR-Z application, or MP6605EGR-Z equivalent, key selection criteria include serial-addressable 4-channel low-side drive capability, VCLAMP-based inductive energy clamping, fault reporting via open-drain nFAULT, and QFN-24 package compatibility with high-density motor control PCB layouts.

Technical Context

The MP6605EGR-Z implements a serially addressed, 3-byte SPI-like protocol (wake-up 0xFEh → address/data → stop 0x7Eh) enabling daisy-chained configuration of multiple devices using A0–A3 address pins. Its internal logic accepts 3.3V/5V-compatible Schmitt-trigger inputs and drives outputs independently while maintaining full serial interface operation during ENBL disable.

Each channel combines a low-side MOSFET with integrated body diode and shares a common VCLAMP pin for external TVS/Zener clamping-critical for managing leakage inductance spikes in unipolar stepper windings. Fault detection (OCP, UVLO, OTP) triggers nFAULT assertion and automatic recovery (2.5ms retry), ensuring robust operation in intermittent-load industrial environments.

Key Specifications

Pinout & Package

MP6605EGR-Z is housed in a thermally enhanced QFN-24 (4mm × 4mm) package with exposed thermal pad (EP, Pin 7) for PCB heat sinking. The pinout supports serial configuration, sensor feedback, and independent output control with dedicated VCLAMP clamping node.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-side serial driver applications.

Compared with TB9051FTG and STSPIN220, MP6605EGR-Z uniquely balances wide-input-voltage serial addressability, integrated VCLAMP clamping, and sensor feedback in a single QFN package-making it optimal for scalable, multi-actuator industrial control where flexibility and thermal efficiency are critical.

Availability

MP6605EGR-Z is available at Aetrix Electronics and suitable for unipolar stepper motor control, solenoid actuation, industrial PLC I/O modules, and automated test equipment requiring stable component supply across extended temperature ranges (−40°C to +125°C).

Supply support for MP6605EGR-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 design expertise in DC/DC converters, motor drivers, and battery management solutions.

The MP6605E product line targets industrial and automation applications requiring robust, serially configurable low-side drivers for inductive loads - emphasizing thermal resilience, fault intelligence, and layout simplicity in space-constrained systems.

FAQ

What is the maximum continuous output current per channel when all four channels are active?

The MP6605EGR-Z supports 700mA maximum continuous output current per channel when all four low-side MOSFETs are simultaneously active. This derating accounts for thermal limitations in the QFN-24 package under typical PCB copper area and airflow conditions; exceeding this value risks thermal shutdown activation.

How does the VCLAMP pin function during inductive load switching?

VCLAMP serves as the common return node for flyback energy from all four output channels. When any OUTx turns off, stored inductive energy flows through the internal clamp diode to VCLAMP, which must be externally clamped to VIN (via TVS or Zener) to limit voltage to ≤60V. Direct connection to VIN provides basic clamping; adding a TVS enables faster current decay for high-speed stepping.

Can the MP6605EGR-Z operate without an external pull-up resistor on the nFAULT pin?

No. The nFAULT pin is an open-drain output and requires an external pull-up resistor (typically 4.7kΩ to 3.3V or 5V) to assert a valid high-level signal during normal operation. Without it, the pin remains floating when no fault occurs, preventing reliable system-level fault detection and interrupt generation.

What happens to the serial interface when the ENBL pin is driven low?

Driving ENBL low disables all four output channels (OUT1–OUT4 go high-impedance), but the serial interface remains fully operational: SDI, SCLK, SCS, and SDO continue to accept commands and report SIN0–SIN2 states. This allows configuration, diagnostics, and sensor polling even while outputs are inactive.

Is the MP6605EGR-Z compatible with 3.3V microcontrollers without level shifting?

Yes. All logic inputs (SDI, SCLK, SCS, ENBL, A0–A3, SIN0–SIN2) feature Schmitt-trigger receivers with 0.7V V_IL and 2.3V V_IH, making them directly compatible with both 3.3V and 5V CMOS logic levels. No external level shifters are required for standard microcontroller interfacing.

How is device addressing implemented in multi-driver configurations?

Addressing uses four hardware pins (A0–A3), each internally pulled up to ~6V. Grounding or leaving pins floating sets a 4-bit binary address (0000–1111); address 0000 is reserved for broadcast mode, where all connected MP6605EGR-Z devices respond to the same command. This enables daisy-chained control with minimal wiring.

Does the MP6605EGR-Z require external bypass capacitors, and if so, what values are recommended?

Yes. A minimum 100nF X7R ceramic capacitor must be placed adjacent to the VIN pin, and a 4.7µF ceramic capacitor is recommended nearby. If the IC is located >2cm from the main power source, additional bulk capacitance (e.g., 10–47µF electrolytic) is advised to suppress supply ripple during high-current switching transients.