As part of a bigger circuit, I am using an H-bridge inverter to get a +-5V square pulse in output. For that I need a 50% duty gate pulse at the gate of the four switches of the inverter. How do I generate that in practice/hardware design?
I tried to use a 555 timer IC to generate the gate pulse, but there were several issues.
i) The output was quite unexpected, instead of getting a +-5V output from inverter, I got an output that took more than 50 ms to settle to this desired result. However it was perfect when I was using a voltage pulse source from Ltspice library (at the gates of the switches).
ii) In my circuit I simply used a behavioral NOT gate to generate the complementary pulse, but in practice how do I invert this pulse to feed to the other switch in each arm?
iii) For the switches on higher side (source not at ground), how do I generate the pulse w.r.t their source voltage? In my simulation I used ideal switches, so it doesn't really matter. But when I use an actual switch like a MOSFET, the voltage at gate needs to be w.r.t source voltage (Vgs should be 10V and 0V). I don't know how to achieve that.
I'm attaching the .asc file that uses the 555 timer.
Any recommendations to make this circuit work or some other way to generate the +-5V output, would be appreciated.
Thanks!

 

Have a look at the IRS2543 it can do the whole thing all in one go.

For a more modern device try a pair of LTC7060. You only need a single squarewave to drive it because you can swap the output stages to make it invert.

 

Have a look at the IRS2543 it can do the whole thing all in one go.

For a more modern device try a pair of LTC7060. You only need a single squarewave to drive it because you can swap the output stages to make it invert.

Thank you so much for the suggestion!
I really liked the first device, as it does not need a PWM input. But problem is too low sink current and I can't find its spice models.
For the second, can you suggest a PWM generator?

 

How about a CD4047? It has a divide by two stage, so you know that the mark-space ratio is exactly 50%.
How accurate so you need the frequency?
A CD4060 and a crystal?
What does it need to drive, and at what frequency?
(I‘m answering on an iPad, so .asc files do me no good!)

 

I need a slightly higher frequency ~50kHz. Does not have to be accurate, I'm only concerned with the order of magnitude.

 

4047 should manage that.

 

I am using a full bridge inverter to get +-5V square wave output from 5V dc. I needed a 50% duty, so I was operating it at that earlier, and the output was fine. But for some purpose I tried a 40% duty, and in that case the output is +-5V initially, but it's increasing with time (difference still remains 10V, but I'm not getting +-5V but 6V and -3V say, at a later time). I have attached the .asc file.
Can anyone explain the reason for this behavior at a different duty, and how to solve this so that I get a +-5V output.

 

LM555 is far not best solution for gate pulses source. First, it have no a proper time gap between both sides. Secondly - it PWM capacity is rather weak and depend on temperature as well the voltage. Beter is IR2153 if there is no need for PWM (start-stop regime) or UC3843...UC3845 if PWM is needed, As the most stable solutions are TL494 with excellent PWM part and it`s precision twin TL594, if You have anything against the skewed bridge.

 

I am using a full bridge inverter to get +-5V square wave output from 5V dc. I needed a 50% duty, so I was operating it at that earlier, and the output was fine. But for some purpose I tried a 40% duty, and in that case the output is +-5V initially, but it's increasing with time (difference still remains 10V, but I'm not getting +-5V but 6V and -3V say, at a later time). I have attached the .asc file.
Can anyone explain the reason for this behavior at a different duty, and how to solve this so that I get a +-5V output.

If your bridge drives a transformer, then it won’t work at anything other than 50% duty cycle, as anything else will saturate the transformer.

 

LM555 is far not best solution for gate pulses source. First, it have no a proper time gap between both sides. Secondly - it PWM capacity is rather weak and depend on temperature as well the voltage. Beter is IR2153 if there is no need for PWM (start-stop regime) or UC3843...UC3845 if PWM is needed, As the most stable solutions are TL494 with excellent PWM part and it`s precision twin TL594, if You have anything against the skewed bridge.

I see, thanks a lot!

 

If your bridge drives a transformer, then it won’t work at anything other than 50% duty cycle, as anything else will saturate the transformer.

Ohh yes, makes sense. Thank you so much

 

It would really help if You would explain for us exactly what You are trying to accomplish overall.
Then explain what You have tried so far, and how it turned-out.

What is your initial Power-Supply ?, ( Battery ?, Solar ?, Mains? )
What are You Powering ?, Split-Supply or Single-Ended ?
How much Current ?
What are your special requirements if any ?
Etc., Etc., Etc.

"H-Bridge" can be a huge subject.
.
.
.

 

It would really help if You would explain for us exactly what You are trying to accomplish overall.
Then explain what You have tried so far, and how it turned-out.

What is your initial Power-Supply ?, ( Battery ?, Solar ?, Mains? )
What are You Powering ?, Split-Supply or Single-Ended ?
How much Current ?
What are your special requirements if any ?
Etc., Etc., Etc.

"H-Bridge" can be a huge subject.
.
.
.

I need a +-5V input to drive a transformer, input is 5V DC supply. That is why I'm using an inverter. I uploaded the .asc file, that is the circuit I am working on. I am looking for an IC that takes a 5V input and includes a half or full bridge driver, that is, the switches and gate drivers in one single IC. I can generate the input PWM pulse from TL494. I am aware that there are several gate driver ICs available, but for compactness of my circuit I am looking for an IC that includes the gate drivers and switches in it, that is, it can take a PWM input, a Vcc of 5V and generate +-5V square wave of 50% duty and adjustable frequency (I need around 50KHz). (Even if it consists of just two switches, it's fine. I can connect two capacitors to make a half bridge inverter configuration)
I found an IC TPM8837 on the Digikey website, but as there's no simulation model available, I have my doubts as to whether it will actually work. If someone could confirm whether it will work, or could suggest another IC, it would be great.

 

This project could be ridiculously simple ........... or not.

But You still have not answered the previous questions,
so no suggestions can be given, only vague assumptions.

What is your initial Power-Supply ?, ( Battery ?, Solar ?, Mains? )
What are You Powering ?, Split-Supply or Single-Ended ?
How much Current ?
What are your special requirements if any ?
Etc., Etc., Etc.
.
.
.

 

I need a +-5V input to drive a transformer, input is 5V DC supply. That is why I'm using an inverter. I uploaded the .asc file, that is the circuit I am working on. I am looking for an IC that takes a 5V input and includes a half or full bridge driver, that is, the switches and gate drivers in one single IC. I can generate the input PWM pulse from TL494. I am aware that there are several gate driver ICs available, but for compactness of my circuit I am looking for an IC that includes the gate drivers and switches in it, that is, it can take a PWM input, a Vcc of 5V and generate +-5V square wave of 50% duty and adjustable frequency (I need around 50KHz). (Even if it consists of just two switches, it's fine. I can connect two capacitors to make a half bridge inverter configuration)
I found an IC TPM8837 on the Digikey website, but as there's no simulation model available, I have my doubts as to whether it will actually work. If someone could confirm whether it will work, or could suggest another IC, it would be great.

SN6501?
(although I still don't know how much power is required)

 

This project could be ridiculously simple ........... or not.

But You still have not answered the previous questions,
so no suggestions can be given, only vague assumptions.

What is your initial Power-Supply ?, ( Battery ?, Solar ?, Mains? )
What are You Powering ?, Split-Supply or Single-Ended ?
How much Current ?
What are your special requirements if any ?
Etc., Etc., Etc.
.
.
.

A battery.
I'm not sure what is meant by a split/single-ended supply, but I need two output terminals, such that when I measure the voltage between them I get a +-5V square wave (50% duty).
Current ~1A
Could you tell if a TL494 can give a 50% duty pulse? I think I read somewhere that its maximum duty is 45%.

 

If You don't know what a split-Supply is,
then how do You know that it needs to run at 50khz ????
Most Circuits running above, oh maybe, ~10khz can start to get tricky, especially for a beginner.

The attached Circuit is really easy to build, and is adjustable from ~71Khz to ~12Khz.
It will probably do what You want if you are using a custom designed high-frequency-Transformer.
It will produce a very clean, and sharp, Square-Wave-Output.
.
.
.

.

 

SN6505A will give 1 Amp
https://www.ti.com/lit/ds/symlink/s...40323&ref_url=https%3A%2F%2Fwww.google.com%2F