From: Jim Thompson
Subject: Re: 68hc11 A/D converter question
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Date: Thu, 26 Dec 2002 22:27:57 GMT
NNTP-Posting-Date: Thu, 26 Dec 2002 17:27:57 EST
Organization: Cox Communications
On Thu, 26 Dec 2002 22:25:26 GMT,
In Newsgroup: sci.electronics.design,
Entitled: "68hc11 A/D converter question",
Wrote the following:
| I am building a single axis joystick for a robot. I will have to use
|a potentiometer(linear) in order to determine the joystick position. I am
|using the A/D on the 68hc11 and have connected a voltage divider circuit as
| +5V <-----/\/\/\-------/\/\/\------GND
| fixed | pot
| resistor |
| Vout(To A/D on 68hc11)
|My problem is that Vout does not vary linearly. It changes faster at lower
|pot values and slower at higher pot values. Is there any way to fix this
|non-linearity? Any suggestions will be appreciated. TIA.
Use the pot wiper as the output rather than the tap between the pot
and the fixed resistor.
Also make sure it's a linear pot, not logarithmic.
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| Jim-T@analog_innovations.com Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |
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