RoadTest: RoadTest the TI INA301EVM
Evaluation Type: Evaluation Boards
Did you receive all parts the manufacturer stated would be included in the package?: True
What other parts do you consider comparable to this product?:
What were the biggest problems encountered?: The biggest problem for me was utilizing the "pre-built" comparator threshold. The problem came form the 0805 SMD resistor, I simply couldn't use it with my application because I didn't(couldn't) get a 0805 SMD resistor that worked for me in the aviable stores around here.
Hello! First of all, I'd like to thank the team at Element 14 for choosing me as one of the winners of this road test and second of all that I took that long to write my review.
The INA301 evaluation board really helped me make my hydroponics project a whole lot awesome.
The problem I was facing was the battery operated system I was about to set up. The project itself was simple: microcontroller, real time clock module, transistor, diode, relay, mini water pump, soil humidity meter, lcd, shunt resistor. All of this is supposed to water my plants at home operating on battery power in case the power goes out when I am not at home on holidays or some other scenario. Now to the problem I was having. I was using the shunt resistor to only measure the current consumption when the water pump was working. This was necessary for me, because I am using an integrator to calculate the total power consumption so I'd know when to change the battery.
With the INA301 module I was able to use the differential voltage from the shunt resistor, while I couldn't read it with the analog input on my microcontroller. This reading allows me to get the total current consumption of the circuit and with that measurement I can calculate exactly how much power I have used/is left in the battery/.
The module itself is really great. It is easy to use because of all the ports in place, it has all the necessary components to utilize every aspect of the EV board(comparator led indication, shunt resistor filtering). I had one problem with the module itself, it wasn't something of a big deal because it can be fixed easily. The problem came form the 0805 SMD resistor for the comparator threshold voltage, I simply couldn't use it with my application because I didn't(couldn't) get a 0805 SMD resistor that worked for me in the aviable stores around here. Apart from that the module didn't have any other problems or flaws I could find. The evaluation board came with three different ICs: INA301A1 with a gain 20 V/V, INA301A2 with a gain 50 V/V, INA301A3 with a gain 100 V/V. Although the package they use is VSSOP8, they came soldered on VSSOP8 to DIP8 boards and could be easily interchanged on the EV board. Also I could easy fit them on a plastic DIP holder on my perf board for my circuit. And having them on my own board, I was able to use the right resistor for the purpose of my project(I simply have low current consumption for the set comparator threshold). Also the response rate is really fast when I have spikes in the power consumption.
Overall the INA301EVM is great. The three ICs it came with can be put in some other projects of mine in the future since they are so easy to set up and use. Also the built in comparator function makes it great for making some sort of a portable overcurrent alarm for some application, say a car amplifier.
Hello, I disconnected my hydroponics system so I can take a clear picture of it. Also I found the pictures of the unboxing I did.
As you can see, the EVM board came in a box with protective material and an ESD bag. Sadly I had to use the internet to figure out how to work with it, but Texas Instruments had a PDF datasheet available on their site which explained everything I needed to know in a simple manner, like I stated in my review. The ICs snap with ease from the board and fit perfectly on the footprint. The board itself is a two layer PCB and I think it could be done on one layer so the cost is cut down, but with the technology we have today, I don't think its such a big deal. Also the board has rubber pads on the bottom at the corners for stability(I guess).
Nowadays I usually make a perfboard(I think they are called that in english, in Bulgaria we use the therm experimental board) prototype, and if I need more than one circuit made I design PCBs and order them. In this case I used only a perfboard protoype, but it does the job.
Here we have the whole circuitry of the project with the additional hardware required. On the right you see the water pump with its corresponding input and output tubing. I disconnected the output tubing from the back push in fitting, because the rest of the tubing is tied to the plants and I didn't want to take that apart. On the top left you can see the 16x2 LCD with a 74HC595 shift register which allows me to use only 3 pins to communicate between the LCD and the microcontroller. On the bottom left is the soil humidity sensor just for indication. I could wire in an equation I came up with for my masters thesis which acts as a regulator for watering systems, but here its not that important. In the middle is the heart of the whole project, you can see it in the following picture.
Here you can see the battery for the RTC circuit, an ARduino Pro Mini, INA301A3, and the other components are LM78L05 and BC337 for the pump. As stated in my review of the EVM board its easy to use the individual ICs with plastic DIP8 holders. For my project I am using a 0,1 ohm 5% 1206 SMD resistor with a total power dissipation of 1/8W. I also mentioned the problem with the current limit resistor, for my circuit since I highly doubt I'd go over 1A the resistor value is 25 kOhm, for which I used a 10 and a 15 kOhm resistors in series. The other components used for the proper exploitation of the INA301A3 are the 10kOhm pull-up resistor for the alert pin and the corresponding output LED with its current limiting resistor.
My program is simple. It reads the input from the INA301A3 and knowing the resistor value I am using, the size of the ADC it calculates the current draw when it runs.(the shunt resistor is right after the input for the power supply) With a simple totalizator I can see how much power I have drawn from my power supply(in my case a battery pack), so I'd know when to recharge/replace it. The other part of the code is also quite simple: it reads the time and when the program reaches the set time for watering it activates the pump via a NPN transistor.
In the future, I could use the remaining ICs to make a project I had in mind, which is monitoring the current consumption of my house using those inexpensive ESP modules, instead of using Hall effect sensors.