Is it possible to create a Heaviside step function with the WaveDAC or PWM?

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Anonymous
Not applicable

Hello everyone,

I'm trying to create a signal that is commonly known as the unit step function:

0, t < value

1, t > value

Does any of you know if this possible with the PSoC 5LP?

Right now, I kinda do it. Implemented a 1 Hz wave with the WaveDAC block.

The final goal is to obtain the capacitor response: https://www.electrical4u.com/images/2017/may/1495305721.GIF

Thanks in advance

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1 Solution
odissey1
Level 9
Level 9
First comment on KBA 1000 replies posted 750 replies posted

TelmoBarros,

It is my understanding that you want stable (referenced) step function with hardware ON/OFF. For that I suggest VDAC8 with hardware enable pin. When it is High, the VDAC provides stable voltage (whatever you set e.g. by API VDAC_Write(128)), when it is LOW, VDAC output is 0 V.

Specifically for capacitor characterization it is better to use IDAC8. In this case the voltage increases linearly,  which is much easy to analyze and process. For example, you may set voltage comparator at 1.24V and count time it takes between IDAC start and Comparator stop events.

/odissey1

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1 Reply
odissey1
Level 9
Level 9
First comment on KBA 1000 replies posted 750 replies posted

TelmoBarros,

It is my understanding that you want stable (referenced) step function with hardware ON/OFF. For that I suggest VDAC8 with hardware enable pin. When it is High, the VDAC provides stable voltage (whatever you set e.g. by API VDAC_Write(128)), when it is LOW, VDAC output is 0 V.

Specifically for capacitor characterization it is better to use IDAC8. In this case the voltage increases linearly,  which is much easy to analyze and process. For example, you may set voltage comparator at 1.24V and count time it takes between IDAC start and Comparator stop events.

/odissey1