Hi all,
I am looking for a logarithmic converter with a voltage input and voltage output. Any suggestion would be very helpful.
Thanks very much,
Regards,
Joseph
- posted
14 years ago
Logarithmic converter
Loading thread data ...
- Vote on answer
- posted
14 years ago
.----------------. .-------------------. | | | | | ||100p |/ \| 100p|| | o---||--. .--| LM394 |-. .-||---o | || | | |> --o '-----)--|___|-o-< | Rref .--|+/ | ___ | 1k5 \+|--. | |/ o---|___|--o-----' \| | === | 15k | AD795 === GND AD549 | .-. GND | | |1k ptc o | |+0.3%/K Vout '-' | === GND (created by AACircuit v1.28.6 beta 04/19/05
formatting link
The output is -1V/decade and the range is around 7 decades, if you put an offset cancellation pot on the AD549, but the response gets slow on the lower end.
- Vote on answer
- posted
14 years ago
Would a software solution using micro be useable - would allow nice tuning etc.
- Vote on answer
- posted
14 years ago
g
If you want to use a micro and need a very wide range, you can place a digitally controlled gain in front of the ADC. If your micro is one with multiple ADC inputs, you can select the input that has the gain you discover is needed.
On the output side, a real DAC would be the best way to go. A PWM based DAC is noisy.