Basic Electronic Queries

Hi Apoorva,

I do not know the answer to your question on the LCD module but I will tell you what I know about the motor question.

If the motor is rated for 5v to 9v this means that the motor will turn dependably at 5 volts and at 9 volts it will be at its full duty cycle voltage. More than 9 volts can be applied for short periods of time but the motor may spin faster than it is designed for when under no load. The current draw of the motor under any specific voltage will increase as load is applied to the motor. For example if we have a motor drawing 1 amp at 9 volts with no load and we make the motor spin a drill bit that is boring so that the drill bit slows the motor the current will increase. We could see the amperage go to 2 amps, 3 amps and so on as more load is applied to the motor. Ultimately too much load will stall the motor and we will get a stall current. This will quickly overheat and burn the windings in the motor. Your power supply will likely have a limit to the current that it can supply. This may prevent damage to the motor but it will also limit the power you can get out of the motor.

Very few motors that I know of are designed to have drill bits attached directly. In most cases the motors are geared down so that the drill bit turns at a slower speed but has a lot more torque. This is of course exactly what is done in a battery powered hand drill. I do not know what you are building but will a battery powered hand drill work. You would have a DC motor and a drill chuck.

John

1.Are 1602 and 16*2 just different names for same LCD module?

Yes

2.How  to identify whether the cheap LCD modules has HD44780 controller board inbuilt?

Consult the manufacturers documentation for the module.

Any supplier that is worth buying from will have this information ... if not find another that does.

Mark

I'm looking at the questions again and wondering what they are all related to.

Is this part of an assignment or homework ??

Mark

Thank you John for your detailed answer!

I was thinking of making drill with USB power supply(5v)

There are videos on YouTube which have done it but do not have a description of motor & power supply used.

The following is a shop based in my area(Link below)

Bombay Electronics - DC Motors

Please suggest motor which would suit best for my need from the above website,also provide the corresponding power supply Voltage & Amperage value I should use with motor on full load.

Awaiting for your advice!

Thanks in advance!

Thank you Mark !

For confirmation and advice on topic!

Hi Mark,

This is not a part of some assignment

Is it strange to have these doubts as a entry level hobbyist?

Is it strange to have these doubts as a entry level hobbyist?

Most people indicate what they want to do  (I was thinking of making drill with USB power supply(5v) ) and then have some questions.

We have seen lots of similar type questions asked before for assignments.

It was the manner and different items that made it seem like assignment type questions.

Mark

Just to add some more useful info on the LCD's - you can often buy them with an i2c backpack which can simplify their usage and reduce the amount of wires to connect to them considerably, by buying one with a backpack you also need not worry about the controller chip as the datasheet will list all of the commands you need to communicate with it through i2c.

Hi Apoorva,

The only size drills that could be successfully utilized with such a small motor and low power power supply would be 1.5 mm or less in diameter. It would also be a challenge to mount the drill concentrically on the motor shaft. Even mounting a small chuck if available would be a challenge. If you were to us a USB power supply choosing the one with the most amperage rating would be your best bet. 2 amps at 5 volts would give you about 10 watts of power available.

John

by buying one with a backpack you also need not worry about the controller chip as the datasheet will list all of the commands you need to communicate with it through i2c.

While I agree that the datasheet will give you the commands, it is based on the underlying controller chipset.

For clarification.

The I2C "backpack" is simply an I2C to 8 bit expander.

They are available already attached or seperately (for a couple of $) to add to most LCD's that use parallel interface. (ie have the 14 or 16 pins)

It simply provides a piece of hardware that converts what you send via the I2C interface into the multiple pins on the LCD.

They also have one big advantage in that they drive the Backlight without an external transistor, since these normally draw more current than a pin on the Arduino can handle.

Mark