Introduction to A4988
Hello friends, I hope you all are doing great. In today's tutorial, we are gonna have a look at detailed
Introduction to A4988. The A4988 is a micro-striding driver for governing the stepper motors, it is incorporated with the interpreter (translator) for the tranquil process. By this controller stepper motor can control by 2 pinouts, one pin is to regulate the direction of motor revolutions and other is for steps regulation of motor.
It works on 3 to 5.5V and it consumes per phase two amperes current in presence of the proper cooling environment. It consists of an immovable off-time current controller which has the capacity to works in sluggish or assorted falling-off styles. In today's post, we will have a look at its cascading, pinout, sorts, uses, etc. I will also share some links where I have interfaced it with other microcontrollers. You can also ask about it in comments, I will direct you additional about it. So, let's get started with a basic
Introduction to A4988.
Introduction to A4988
- The A4988 is a micro-striding driver for governing the stepper motors, it is incorporated with the interpreter for the tranquil process.
- This motor driver offers five, unlike step tenacities which are, 1. Complete Step 2. Half (1/2) Step 3. A quarter (1/4) Step 4. Eight (8th) Step and 5. 16-Step. It also has a potentiometer which regulates the output current, over temperature updraft stoppage and crossover current safety.
- The interpreter of this driver is fundamental to the stress-free employment of the A4988. Only entering one pulse on the stride input drives the motor one micro-step.
- There is no need for phase classification tables, higher frequency outlines, or multifaceted borders to plug-in.
- The interfacing of this module is suitable for such applications where a composite microprocessor is inaccessible or is overloaded.
- During the stepping process, the cutting governer in this module robotically chooses the current falling-off way, sluggish or diversified.
- In diversified decay style, the expedient is set firstly to a fast deterioration for a magnitude of the steady off-time, then to a slow deterioration for the remains of the off-time.
- In this module, interior synchronous modify integrated circuit is connected to mend power indulgence during the PWM process.
- This special integrated circuit consists of thermal cessation with hysteresis, under voltage lockout (UVLO), and crossover-current fortification
- It is available in superficial mounted QFN cascading (ET), with the dimensions of 5mm x 5mm, having a cascading height of .90mm and an uncovered wad for boosted thermal indulgence.
Pinout of A4988
- These are the main pinout A4988 which are described below.
| Pin# |
Type |
Parameters |
| Pin#4 |
CP1 |
It is a charge drive capacitor point. |
| Pin#5 |
CP2 |
It is a charge drive capacitor point. |
| Pin#6 |
VCP |
It is a reservoir capacitor point. |
| Pin#8 |
VREG |
It is controller decoupling point. |
| Pin#9 |
MS1 |
It is a Logic input pinout. |
| Pin#10 |
MS2 |
It is reasoning input pin. |
| Pin#11 |
MS3 |
It is reasoning input pin. |
| Pin#12 |
RESET |
It is reasoning input pin. |
| Pin#13 |
ROSC |
It is timing setting pin |
| Pin#14 |
SLEEP |
It is reasoning input pin. |
| Pin#15 |
VDD |
It is the Logic source. |
| Pin#16 |
STEP |
It is reasoning input pin. |
| Pin#17 |
REF |
It is Gm reference voltage input pinout. |
| Pin#3,18 |
GND |
It is ground pinout. |
| Pin#19 |
DIR |
It is a reasoning input pin |
| Pin#21 |
OUT1B |
DMOS Complete Bridge 1 Output B pin. |
| Pin#22 |
VBB1 |
It is a supply voltage for load. |
| Pin#23 |
SENSE1 |
It is sagacity resistor terminal for Bridge. |
| Pin#24 |
OUT1A |
DMOS Complete Bridge 1 Output A pin. |
| Pin#26 |
OUT2A |
DMOS complete Bridge 2 Output A pin. |
| Pin#7,20,25 |
NC |
It is open pinout. |
| Pin#1 |
OUT2B |
It is DMOS Complete Bridge 2 Output B |
| Pin#27 |
SENSE2 |
Sagacity resistor terminal for Bridge 2. |
| Pin#28 |
VBB2 |
It is a supply voltage for load.Pin#2ENABLEIt is Logic input pinout. |
| - |
PAD |
It is unshielded wad for improved thermal indulgence. |
Let's see a pinout diagram.
Features of A4988
- These are some features of A4988. Let's discuss them.
- It has a squat RDS (ON) every output pinout.
- It has Instinctive current falling-off type assortment.
- It has Varied and Sluggish current falling-off modes.
- It provides coetaneous rectification for low-slung power indulgence.
- This module has an interior UVLO.
- It provides crossover current fortification.
- It is well accorded with the 3.3 and 5 v logic source.
- It has thermal cessation circuit.
- It also provides fortification from short to ground.
Difference between A4988 and DRV8825
- Now we discuss differences between A4988 and DRv8825.
- The DRV8825 proposals to 1/32 striding, while A4988 only steps to 1/16.
- Both have potentiometer at the dissimilar place.
- There is no coherence between a reference voltage and current limiter.
- DRV8825 needs the smallest step pulse period of 1.9us, while A4988 needs 1us.
- DRV8825 used for high current consuming motors, while A4988 is used for low current consuming motors.
- In the case of A4988, we need special colling to draw high current but in the case of DRV8825, there is no need for any special colling.
Applications of A4988
- These are some applications of A4988.
- As we discussed it is used to control the speed and rotation of stepper motor.
- It is used in robotics to control their motion.
- It is used in different toys.
So, friends, it was all about A4988, if you want to know something more about it please ask in comment. Take care until the next tutorial.