Conversion product from capacitance to PWM clock

Koji Ikeda

Expert 5335 points

Other Parts Discussed in Thread: FDC2214

Hello support team,

My customer is looing for Conversion product from capacitance to PWM clock. Could you tell me your suggestion?

Cap range: 1pF up to 50pF

Expected output frequency: 150 or 160kHz to 200kHz. (1k Hz per 1pF)

Thanks,

Koji Ikeda

over 5 years ago

0 Clancy Soehren over 5 years ago

TI__Mastermind 23810 points

Koji,

The FDC2214 can provide a digital capacitance output, but you would need to pair it with an MCU to create a PWM output signal.

0 Koji Ikeda over 5 years ago in reply to Clancy Soehren

TI__Expert 5335 points

Clancy-san,

Thank you for your support. I don't see FDC2214 on TI.com product seach, can FDC2214 provide proper support now?
www.ti.com/.../products.html

And additional MCU is not good for system. Do you have any ohter solution?

Thanks,
Koji Ikeda

0 Clancy Soehren over 5 years ago in reply to Koji Ikeda

TI__Mastermind 23810 points

Koji,

There is no other option for a PWM output as you described. We do have devices that have interrupt output pins that will indicate when the data crosses a certain threshold.

If you search directly for the part number, then you can find the product folder. It is here:
www.ti.com/.../FDC2214

0 Koji Ikeda over 5 years ago in reply to Clancy Soehren

TI__Expert 5335 points

Clancy-san,

Thank you for your support.
I have another question, can timer IC like LMC5555 support their usage? Timer IC is very popular for PMW generator.

Thanks,
Koji Ikeda

0 Clancy Soehren over 5 years ago in reply to Koji Ikeda

TI__Mastermind 23810 points

Koji,

The FDC2214 supports I2C output. I do not think that you can convert this to PWM using a 555 without an intermediate step.

Clock & timing

Clock & timing forum

Conversion product from capacitance to PWM clock