Overview
The DRV8821, produced by Texas Instruments, is a dual stepper motor controller and driver designed for applications requiring independent control of two stepper motors. This device integrates four N-channel MOSFET H-bridges, a microstepping indexer, and various fault protection features. It is suitable for use in printers, scanners, office automation machines, gaming machines, factory automation, and robotics.
The DRV8821 operates with a supply voltage range of 8 to 32 volts and can provide an output current of up to 1.5 amps per winding. It features a simple step/direction interface for easy interfacing with controller circuits and supports full-step, half-step, quarter-step, and eighth-step microstepping modes. The device also includes internal charge pump for gate drive, built-in 3.3-volt reference, and thermal shutdown protection.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Motor Power Supply Voltage (VM) | 8 to 32 | V |
| Continuous Motor Drive Output Current (IMOT) | 1 to 1.5 | A |
| VREF Input Voltage | 1 to 4 | V |
| Junction-to-Ambient Thermal Resistance (RθJA) | 31.3 | °C/W |
| Junction-to-Case (Top) Thermal Resistance (RθJC(top)) | 16.3 | °C/W |
| Package Type | HTSSOP (48 pins) | |
| Body Size (Nominal) | 6.10 mm x 12.50 mm |
Key Features
- Dual PWM microstepping motor driver capable of driving two independent stepper motors.
- Up to 1.5-A current per winding.
- Three-bit winding current control allowing up to eight current levels.
- Low MOSFET on-resistance.
- Selectable slow or mixed decay modes.
- Internal charge pump for gate drive and built-in 3.3-V reference.
- Simple step/direction interface for easy interfacing with controller circuits.
- Fully protected against undervoltage, overtemperature, and overcurrent.
- Thermally-enhanced surface mount package.
Applications
- Printers
- Scanners
- Office automation machines
- Gaming machines
- Factory automation
- Robotics
Q & A
- What is the operating voltage range of the DRV8821?
The DRV8821 operates with a supply voltage range of 8 to 32 volts.
- What is the maximum output current per winding of the DRV8821?
The DRV8821 can provide an output current of up to 1.5 amps per winding.
- What microstepping modes does the DRV8821 support?
The DRV8821 supports full-step, half-step, quarter-step, and eighth-step microstepping modes.
- What protection features does the DRV8821 include?
The DRV8821 is fully protected against undervoltage, overtemperature, and overcurrent events.
- What is the package type of the DRV8821?
The DRV8821 is packaged in a 48-pin HTSSOP package.
- How does the DRV8821 handle thermal management?
The DRV8821 includes thermal shutdown protection and is designed with thermally-enhanced surface mount packaging.
- What is the purpose of the internal charge pump in the DRV8821?
The internal charge pump is used for gate drive.
- How does the DRV8821 support current regulation?
The DRV8821 supports current regulation through a three-bit winding current control, allowing up to eight current levels.
- What are the typical applications of the DRV8821?
The DRV8821 is typically used in printers, scanners, office automation machines, gaming machines, factory automation, and robotics.
- How does the mixed decay mode work in the DRV8821?
The mixed decay mode begins as fast decay but switches to slow decay after 75% of the PWM cycle, only active when the current through the winding is decreasing.
