| ??? 02/08/05 09:24 Read: times |
#86877 - PC817 optocoupler design aspects |
For a particular application I am reading the motor rpm with reluctance type of sensor and interfacing it to the MCU circuit with a PC817 optocoupler.
The drive motor is variable speed AC drive and you would have guessed what follows next - noise !! The PC817 data sheet specifies the response time(Rise) as 4us with a load of 100 Ohm and Vcc of 5V. In my case the load is at about 1 kOhm and Vcc is 5V. What I am keen to know is whether by properly dimensioning the load resistance, whether the response time can be altered up or down ? (or) Does it have anything to do with the noise rejection ? ( my valid input signal extends upto 6kHz and I want to cut down anything above it ) I have set the LED input current at about 15mA. While the machine is running OK , I would like to improve upon the stability of the RPM values. Any tips-n-tricks? Thanks. Raghu |
| Topic | Author | Date |
| PC817 optocoupler design aspects | 01/01/70 00:00 | |
| For AC i use the PC814 | 01/01/70 00:00 | |
| not this way | 01/01/70 00:00 | |
| PC817 | 01/01/70 00:00 | |
| assorted comments | 01/01/70 00:00 | |
| Optocoupler | 01/01/70 00:00 | |
| Opto Coupler Design Guide | 01/01/70 00:00 | |
So far so good.. | 01/01/70 00:00 |