I have a number of the AD725 chips, wide SOIC -> DIP adapters, and all of the other miscellaneous components on hand, and I am now drawing up how I am going ot lay it all out on the stripboard.
My question is about the logical high at TTL levels needed for the NTSC select, and the 'power on' select at pin 5. Since I only expect to use NTSC, ever, and if the chip has power, it should be on, I need to get a high level signal to these two points. My question is, what is the best way to send that signal? Should I:
1. Just wire it straight to the +5v line.
2. Connect it to the +5v line via a pull up resistor of X ohms?
3. Go through the hassle of adding in an inverter, shorting the input of one inverter gate to GND, and connecting the output of that gate to the two points?
Any suggestions appreciated.
My question is about the logical high at TTL levels needed for the NTSC select, and the 'power on' select at pin 5. Since I only expect to use NTSC, ever, and if the chip has power, it should be on, I need to get a high level signal to these two points. My question is, what is the best way to send that signal? Should I:
1. Just wire it straight to the +5v line.
2. Connect it to the +5v line via a pull up resistor of X ohms?
3. Go through the hassle of adding in an inverter, shorting the input of one inverter gate to GND, and connecting the output of that gate to the two points?
Any suggestions appreciated.