Monolithic Power Systems Inc. MP6605EGR-P

Overview

MP6605EGR-P from Monolithic Power Systems is a 4-channel low-side driver IC with serial interface, integrating four N-channel MOSFETs (R_DS(ON) = 350 mΩ) and clamp diodes for inductive load control. It operates from 4.5V to 60V input, delivers up to 1.5A per channel (single-FET on), includes OCP, UVLO, OTP, and fault reporting via open-drain nFAULT - designed specifically for unipolar stepper motor and solenoid drive applications.

For engineers reviewing the MP6605EGR-P datasheet, MP6605EGR-P pinout, MP6605EGR-P application, or MP6605EGR-P equivalent, key selection criteria include serial-addressable 4-channel low-side switching capability, 60V clamp voltage support, thermal shutdown behavior, and compatibility with 3.3V/5V logic interfaces in space-constrained industrial motion control designs.

Technical Context

The MP6605EGR-P implements a serial command protocol using SCLK/SDI/SDO/SCS with wake-up (0xFEh) and stop (0x7Eh) bytes, supporting broadcast (ADDR=0x0) and individual addressing via A0–A3 pins. Each command writes output states and reads back SIN0–SIN2 sensor inputs in a fixed 3-byte frame.

It integrates internal gate drivers, high-side clamp diode paths tied to VCLAMP, and protection circuitry that disables all outputs during over-current (IOCP = 1.5A typ), under-voltage (VIN_RISE = 4.5V), or over-temperature (TTSD = 155°C) events - with automatic recovery after deglitch and retry timing (tOCP = 3.5 µs, tOCR = 2.5 ms).

Key Specifications

Pinout & Package

MP6605EGR-P is housed in a thermally enhanced QFN-24 (4mm × 4mm) package with exposed thermal pad (EP), optimized for high-power density motor drive layouts. Pin 7 and EP are both GND connections for low-impedance return path and thermal dissipation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TB6612FNG and STSPIN250, the MP6605EGR-P uniquely combines 4-channel serial addressability, integrated VCLAMP clamping, and unified fault reporting - reducing component count and firmware complexity in multi-solenoid or multi-winding stepper systems.

Availability

MP6605EGR-P is available at Aetrix Electronics and suitable for unipolar stepper motor control, industrial solenoid actuation, and PLC I/O expansion requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for MP6605EGR-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, with design centers across Asia and North America and global distribution infrastructure.

The MP6605EGR-P belongs to MPS's industrial motor driver product line, engineered specifically for compact, reliable, and serially configurable control of inductive loads in harsh environments - emphasizing thermal robustness, integrated protection, and minimal external component count.

FAQ

What is the maximum allowable voltage on the OUTx pins?

The absolute maximum voltage on OUT1–OUT4 is +65V, but the recommended operating maximum is 60V - matching the VCLAMP clamp rating. Exceeding 60V risks triggering over-voltage protection or damaging internal clamp structures, especially during inductive flyback without proper external TVS diode selection.

Can MP6605EGR-P drive bipolar stepper motors?

No - MP6605EGR-P is a low-side-only driver with no high-side switching capability or complementary output pairs. It lacks the H-bridge topology required for bipolar stepper control; it is explicitly designed for unipolar stepper windings where one side connects to VIN and the other is switched to GND.

How does the serial interface handle multiple devices on the same bus?

Each MP6605EGR-P uses A0–A3 pins to set a unique 4-bit slave address (0x1–0xF); the broadcast address 0x0 allows simultaneous command transmission. SCS is device-selective, and SDO outputs are open-drain to prevent bus contention - enabling up to 15 independent devices on one 4-wire serial bus.

Is an external pull-up resistor required for nFAULT?

Yes - nFAULT is an open-drain output. An external pull-up resistor (typically 4.7kΩ to 3.3V or 5V) is mandatory to establish a valid high state when no fault is present. Without it, the pin remains floating and cannot signal fault clearance reliably.

What thermal vias are recommended for the QFN-24 exposed pad?

MPS recommends ≥9 thermal vias (0.3mm diameter, 0.5mm pitch) under the EP pad, connected to an internal or bottom-layer solid GND plane. This achieves θ_JA ≈ 42°C/W on a 4-layer PCB - critical to sustain 1.5A per channel without exceeding 125°C junction temperature.

Does the MP6605EGR-P support PWM dimming or variable current control?

No - it is a digital on/off driver only. Output current is determined by external load resistance and VIN; no internal PWM generator, current DAC, or analog dimming interface is provided. For adjustable current, external PWM gating of ENBL or serial command rate is required.

What happens to the outputs when ENBL is low?

When ENBL is logic low, all OUT1–OUT4 are forced into high-impedance (off) state regardless of serial register contents. The serial interface remains fully functional - allowing configuration updates and sensor reads - enabling safe power sequencing and dynamic reconfiguration without interrupting bus communication.