6 Replies Latest reply on Mar 8, 2014 11:17 AM by DaKn_263916

Hi there,

we are a group of three and we are doing a project of measuring the voltage output of a circuit using PSoC5 Development kit and display the output voltage on PC. we already finished on interfacing the PSoC5 to PC but our problem is we don't know how will the PSoC5 will read the voltage as the voltage output range is from -14 volts to +14 volts DC. and the PSoC5 only has an input range of 0 to +5 Volts.

is there a circuit that can convert or compare the voltage output of our circuit and hsrink it to a range of 0 to 5 volts.?? this method may bring the voltage measuring accuracy down but it think this is the best way to measure the voltage of the circuit.

• ###### 1. Re: PSoC5 ADC

You have two problems -

1) Total range too great, so use a R divider to bring range down to 5 V.

2) Generate a new offset, see attached simple methods to do that.

Regards, Dana.

• ###### 2. Re: PSoC5 ADC

thank you sir we will try this on our project

• ###### 3. Re: PSoC5 ADC

It's my understanding that the analog votlage range is 0-1.024V, not 0-5V. Under "Absolute Maximum Ratings" in the datasheet for the CY8C58xx parts I see 2V as the maximum analog voltage, and the internal reference is 1.024V.

• ###### 4. Re: PSoC5 ADC

I stand corrected; you can get from 0-5V but the ADC will use its gain stage to reduce the input to 0-1.25V (5V * 0.25).

• ###### 5. Re: PSoC5 ADC

Take a look atr datasheet for Vref selection and ADC range.

Regards, Dana.

• ###### 6. Re: PSoC5 ADC

If you bypass buffer you can exceed Vdda by 100 mV -