Allegro MicroSystems Inc. 1A Dual Full Bridge 1/8 Microstep Driver W/Ocp A4985SETTR-T

The A4985 is a complete microstepping motor driver with built-in translator for easy operation. It is designed to operate bipolar stepper motors in full-, half-, quarter-, and eighth-step modes. Step modes are selectable by MSx logic inputs. It has an output drive capacity of up to 35 V and ±1 A. The A4985 includes a fixed off-time current regulator which has the ability to operate in slow or mixed decay modes.

The ET package meets customer requirements for no smoke no fire (NSNF) designs by adding no-connect pins between critical output, sense, and supply pins. So, in the case of a pin-to-adjacent-pin short, the device does not cause smoke or fire. Additionally, the device does not cause smoke or fire when any pin is shorted to ground or left open.

The translator is the key to the easy implementation of the A4985. Simply inputting one pulse on the STEP input drives the motor one microstep. There are no phase sequence tables, high frequency control lines, or complex interfaces to program. The A4985 interface is an ideal fit for applications where a complex microprocessor is unavailable or is overburdened.

During stepping operation, the chopping control in the A4985 automatically selects the current decay mode, Slow or Mixed. In Mixed decay mode, the device is set initially to a fast decay for a proportion of the fixed off-time, then to a slow decay for the remainder of the off-time. Mixed decay current control results in reduced audible motor noise, increased step accuracy, and reduced power dissipation.

Internal synchronous rectification control circuitry is provided to improve power dissipation during PWM operation. Internal circuit protection includes: thermal shutdown with hysteresis, undervoltage lockout (UVLO), and crossover-current protection. Special power-on sequencing is not required.

The A4985 is supplied in three surface mount packages: two QFN packages, the 4 mm × 4 mm, 0.75 mm nominal overall height ES package, and the 5 mm × 5 mm × 0.90 mm ET package. The LP package is a 24-pin TSSOP. All three packages have exposed pads for enhanced thermal dissipation, and are lead (Pb) free (suffix –T), with 100% matte tin plated leadframes.

IC MTR DRVR BIPOLAR 3-5.5V 32QFN

Manufacturer: Allegro MicroSystems, LLC
Win Source Part Number: 909023-A4985SETTR-T
Operating Temperature Range: -20°C ~ 150°C (TJ)
Features: Bipolar Motor Driver DMOS Logic 32-QFN (5x5)
Package: 32-VFQFN Exposed Pad
Package: Reel - TR
Mounting: Surface Mount
Family Name: A4985
Categories: Integrated Circuits (ICs)
Case / Package: 32-QFN (5x5)
ECCN: EAR99
Popularity: High
Fake Threat In the Open Market: 82 pct.
Supply and Demand Status: Balance
Quantity per package: 9000
MSL Level: 2 (1 Year)
Estimated Pruduction Lead Time: 7 Weeks
REACH Status: REACH Unaffected
HTSUS: 8542.39.0001
Other Part Number: 620-1457-6, 620-1457-2, A4985SETTRT, A4985SETTR-T-ND, 620-1457-1

Bipolar Motor Driver DMOS Logic 32-QFN (5x5)

Bipolar Motor Driver DMOS Logic 32-QFN (5x5)

Bipolar Motor Driver DMOS Logic 32-QFN (5x5)

IC MTR DRVR BIPOLAR 3-5.5V 32QFN

Bipolar Motor Driver DMOS Logic 32-QFN (5x5)