Stepper motor driver circuit

Stepper Motor Data

• Stepper Motor Data 1
• Stepper Motor Data 2
• Stepper Motor Data 3
• Microstepping Data

Stepper Motor Driver Circuit

• 2A Step Motor Driver Circuit
• bipolar stepper motor with current control
• Microstep Stepper motor driver circuit
• Precision Microstepping Driver Circuit
• High Current Microstep Stepper Motor Driver

High Current Microstep Stepper Motor Driver

High Current Microstep Stepper Motor Driver
with protection
The TMC236 / TMC236A (1) is a dual full bridge driver IC for bipolar
stepper motor control applications. It is realized in a HVCMOS
technology combined with Low-RDS-ON high efficiency MOSFETs
(pat. pend.). It allows to drive a coil current of up to 1500mA even at
high environment temperatures. Its low current consumption and high
efficiency together with the miniature package make it a perfect
solution for embedded motion control and for battery powered devices.
The low power dissipation makes the TMC236 an optimum choice for
drives, where a high reliability is desired. Internal DACs allow
microstepping as well as smart current control. The device can be
controlled by a serial interface (SPI™i) or by analog / digital input
signals. Short circuit, temperature, undervoltage and overvoltage
protection are integrated.

Feature

• Control via SPI with easy-to-use 12 bit protocol or external
analog / digital signals
• Short circuit, overvoltage and overtemperature protection integrated
• Status flags for overcurrent, open load, over temperature, temperature
pre-warning, undervoltage
• Integrated 4 bit DACs allow up to 16 times microstepping via SPI
(can be expanded to 64 microsteps)
• Any resolution via analog control
• Mixed decay feature for smooth motor operation
• Slope control user programmable to reduce electromagnetic emissions
• Chopper frequency programmable via a single capacitor or external clock
• Current control allows cool motor and driver operation
• Internal open load detector
• 7V to 34V motor supply voltage (A-type)
• Up to 1500mA output current and more than 800mA at 105°C
• 3.3V or 5V operation for digital part
• Low power dissipation via low RDS-ON power stage
• Standby and shutdown mode available

TMC236 Datasheet pdf

Precision Microstepping Driver Circuit

PBM 3960 is a dual 7-bit+sign, Digital-to-Analog Converter (DAC)
Especially developed to be used together with the PBL 3771,
Precision Stepper Motor driver in micro-stepping applications.
The circuit has a set of input registers connected to an 8-bit data port
for easy interfacing directly to a microprocessor. Two registers are
used to store the data for each seven-bit DAC, the eighth bit being a
sign bit (sign/ magnitude coding). A second set of registers are used
for automatic fast/slow current decay control in conjunction with
the PBL 3771, a feature that greatly improves highspeed micro-stepping
performance. The PBM 3960 is fabricated in a high-speed CMOS
process.

Key Features
- Analog control voltages from 3 V down to 0.0 V.
- High-speed microprocessor interface.
- Automatic fast/slow current decay control.
- Full-scale error ±1 LSB.
- Interfaces directly with TTL levels and CMOS devices.
- Fast conversion speed, 3 ms.
- Matches PBL 3771.

PBM 3960 Datasheet pdf

Stepper motor driver circuit Index

Microstepping Data

Microstepping of Stepper Motors
Let's now look at what current ratios are needed to produce a particular
step angle. The Microstep angle can be graphically represented with
a Phasor Diagram. (See diagram below) The X and Y axis indicate
the current level in two respective coils A, B. A vector (ray from origin
to coordinate X,Y) shows the resultant angle and Torque (magnitude
of the vector) when some current is applied to both coils. Keep in mind
that this diagram shows the 'sub-angle' between natural whole steps
(poles) of the motors. On a typical 200 step per revolution motor this
is 1.8 degrees. The graph below is a representation of how that angle
can be further sub-divided.
http://www.stepperworld.com/Tutorials/pgMicrostepping.htm

Microstepping Tutorial
If the controller is designed with the capability to control the magnitude
of the current in each winding, then microstepping can be implemented.
The phase diagrams below all show different implementations of "divide
by 4" microstepping. Note that it is the phasor angle (not it's length) that
determines the microstep position.

http://www.zaber.com/wiki/Microstepping_Tutorial

Stepping Motor Physics
Microstepping allows even smaller steps by using different currents
through the two motor windings

For a two-winding variable reluctance or permanent magnet motor,
assuming nonsaturating magnetic circuits, and assuming perfectly
sinusoidal torque versus position curves for each motor winding
http://www.suc-tech.com/technology/stepcontrol2.htm