Monolithic Power Systems Inc. EV6500A-U-00A

Overview

EV6500A-U-00A from Monolithic Power Systems is an evaluation board for the MP6500A bipolar stepper motor driver IC, demonstrating full/half/quarter/eighth-step microstepping operation with VSET-based current control up to 2.5A per phase at 35V supply. It features on-board step/dir logic switches (SW1), external signal connectors (CN1, EXT_STEP), and adjustable current limit via RV1 and JP1.

For engineers reviewing the EV6500A-U-00A datasheet, EV6500A-U-00A pinout, EV6500A-U-00A application, or EV6500A-U-00A equivalent, this board enables rapid validation of MP6500A integration in motion control systems requiring precise current-limited bipolar stepper actuation, flexible step resolution selection, and configurable sleep/enabled states.

Technical Context

The EV6500A-U-00A implements the MP6500A's internal microstepping translator and current regulation architecture, supporting four discrete step modes selected by MS1/MS2 logic levels. Its VSET interface accepts 0–2V analog input to set output current limit from 0A to 2.5A with ±5% accuracy under thermal stability conditions.

Board-level power delivery includes 100µF bulk input capacitance (C1), dual 10µF ceramic output caps (C5/C6), and dedicated decoupling for VCP charge pump and AGND separation. All control signals-DIR, STEP, nENBL, nSLEEP-are accessible via headers or manual switches with 3.3V/5V-compatible pull-up support.

Key Specifications

Availability

EV6500A-U-00A is available at Aetrix Electronics and suitable for industrial automation prototyping, robotics motion subsystem validation, and medical device actuator development requiring stable component supply and verified reference design implementation.

Supply support for EV6500A-U-00A 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 over two decades of innovation in DC/DC converters, motor drivers, and battery management solutions.

The EV6500A-U-00A belongs to MPS's evaluation board product line, designed specifically to accelerate adoption of their MP6500A stepper driver by providing fully tested hardware, documented schematics, and validated layout practices for motion control applications.

FAQ

What is the purpose of the JP1 jumper on the EV6500A-U-00A?

JP1 selects between external VSET voltage injection (open) and onboard potentiometer RV1 control (closed). When closed, RV1 adjusts the VSET voltage from 0 V to 2 V, directly setting the MP6500A's output current limit. This configuration requires a 3.3 V or 5 V VCC supply for proper pull-up biasing of control inputs.

Can the EV6500A-U-00A drive unipolar stepper motors?

No. The EV6500A-U-00A is designed exclusively for bipolar stepper motors using H-bridge outputs (AOUT1/AOUT2/BOUT1/BOUT2). Its internal architecture lacks center-tap switching capability required for unipolar motor excitation, and no provision exists for disabling one winding or reconfiguring phase connections.

How is fault reporting implemented on this evaluation board?

Fault status is reported via the NFAULT open-drain output pin of the MP6500A, routed to header pin "FLT" and test point "STEP, FLT". It asserts low during overcurrent, thermal shutdown, or undervoltage lockout events. An external pull-up resistor (R1 = 100 kΩ) ensures defined logic level when inactive.

Does the board include a charge pump capacitor for the MP6500A's internal gate driver?

Yes. Two 1 µF ceramic capacitors (C3 and C4) are placed across CP1 and CP2 as specified in the MP6500A datasheet for stable charge pump operation. These enable high-side MOSFET gate drive at full 35 V supply without external bootstrap components.

Is external VCC required even when using SW1 for manual control?

Yes. SW1 provides logic-level DIR and STEP signals but relies on external 3.3 V or 5 V VCC applied to the VCC header to power internal pull-ups and ensure correct logic thresholds for nENBL, nSLEEP, MS1, and MS2. Without VCC, switch inputs float and may cause undefined behavior.

What is the role of the RV2 potentiometer on the board?

RV2 adjusts the ROSC timing resistor value connected to pin 4 of U1, enabling fine-tuning of the MP6500A's internal oscillator frequency. This affects PWM switching frequency and thus impacts motor noise, efficiency, and thermal performance-critical for optimizing acoustic and EMI behavior in final designs.