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MSP430F2001 Comparator

Robin Padden

Prodigy 20 points

Other Parts Discussed in Thread: MSP430F2001

One input to MSP430F2001 comparator a+ is 1.25V reference and other input is a voltage divider off a DC source we are wanting to determine when it exceeds a certain value. When the divided DC source input is below reference, it works fine but when it tries to go above the reference voltage, it's clamped at reference voltage level. Need it to be able to go above the reference voltage also. Supply to part is 3.6Vdc.

over 14 years ago

0 vikas dabas over 12 years ago

Intellectual 670 points

Connect the Gnd of both voltage together.

And Use Pullup at i/p port

0 Jens-Michael Gross over 12 years ago

Guru 227245 points

What is your circuitry? A simple voltage divider between VCC and GND and the middle point connected to the input?

Maximum common-mode input voltage is VCC-1V.

What is your init code?

0 vikas dabas over 12 years ago in reply to Jens-Michael Gross

Intellectual 670 points

One more thing you should absolute care that power supply must be different from what you are using for msp430 device.

Otherwise it will make one more parallel resistance which affect original resistance formed due to potential devider.

And last, don't take output from formulas available on net. They are wrong for me.

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