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SPWM using PIC16F684 –  I’m generating SPWM using PIC16F684 microcontroller for an inverter circuit. I followed Tahmid’s blog and am using his code to get an SPWM output. I have simulated the design on Proteus and I got the similar output as he did, but when I build this design on hardware I didn’t get similar output. I’m attaching my results kindly tell me what is the issue in it? Read more

 

 

Need help for PIC12f675 – I want to make simple circuit but I can’t understand it. Everything is ok here but the yellow LED is not blinking. Which code can I add for a blinking yellow LED. Read more

Controlling a tungsten lamp using microcontrollers – I would like to a control tungsten lamp. The lamp will operate at 12 V dc from a battery. The lamp will take a maximum 1.5A from the power supply. Do I use PNP or NPN transistor to control the lamp? Read more

Simple circuit of 7-segments – I want to help in this simple circuit, if I press the button, it stops the count. Read more

PIC18f452 for three phase sequence identification– I am trying to find out the phases of the given supply, the project main aim to protect the three phase motor if any wrong sequence given to motor. I am giving three phase AC voltage (5 V) with different phases, let us assume R Y B to the RA0 RA1 RA2. I am taking each phase 30 samples, but I cant find it out which phase is that. How to find the phase starting point or ending point. Can you check the code and give me an idea of how to find the phase sequence? Read more

Why does this audio DAC need external filter in spite of having internal filtering? – The CS4334 is an Audio DAC. It already has internal on-chip filtering and interpolation capabilities as clear from datasheet page 12 Figure 8. I assume that this means that no filter is require to remove the high-frequency components that are typical of outputs on DACs. However, the recommended connection diagram on page 4 Figure 1 of the datasheet looks like this:

Questions:
(1) Why are there networks of resistors and capacitors at the output?
(2) Why is load shown as resistive, should it not be inductive as speakers are represented? If a power amplifier is being used at the output than this makes sense.
(3) Why is there in arrow pointed to right after the RL as if the signal goes beyond the RL?
(4) Why is C dependant on the load? Certainly if we want to get a specific frequency response, we should have fixed values for RC in the high and low pass filters. Read more

Hex file for 8086 microprocessor in Proteus – I have a simulation project with Proteus and the 8086 microprocessor. How do I create a Hex file for the 8086? Read more

How to generate 13 pulses of PWM signal from microcontroller? – I am working on a project and I don’t know how to generate only 13 pulses of PWM from a microcontroller at every 1 second. I am using an ATmega16. Read more

USB Type-C for 230v power supply and 5V DC voltage –  I’m willing to use USB Type-C to connect a power supply from one point to another point — upper two LEDs for AC 230V and lower two LEDs for 5V DC voltage. Will there be any problems?   Read more

STM32f103 ARM microcontroller doesn’t program twice – I have an STM32f103RB and I made a program with STMCUBEMX and IAR. The program is for a test and it is an LED blinker. After I program it for the first time it’s Ok but it doesn’t program again. The MCU is running correctly but I can’t program it again. Read more