You can use a fet or transistor to PWM drive a resistor connected to +10V rail. That way, the PWM signal will be 0-10V, so you will have full control of your analog output signal after filtering. The opamp option will work, but you will lose about a volt in each rail, unless you use true rail to rail opamps, and will need a negative power supply to make it work. The transistor, maybe a BC548, will do the job without problems. Rafael Fraga ----- Original Message ----- From: Lee Wright To: Sent: Sunday, January 04, 2004 10:29 AM Subject: [PIC:] Scaling 0-5v to 0 to 10v Dear People, I hope no-one minds me posting another question so soon after my one about serial comms and 628 but anyway. I am using a 16f84 to act as a 4 channel Digital to Analog converter using PWM. It seems to work OK but what I really need to do is scale it so that it is 0 to 10v rather than 0 to 5. This is just a signal voltage so very little load. Appreciate any comments. Regards, Lee. -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details. -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.