Trevor Rymell
Member
Dear All
How to increase the voltage/current output from a flip-flop.
I’m using a large 7-segment common anode LED driven from a 7447 decoder/driver. The LED has 2 anodes which are used to switch the LED from red to green with a SPDT switch.
I want to replace the SPDT switch with a push-to-make button (for reasons that seemed good at the time) so I put in a 7453 J-K flip-flop (with a 7414 to debounce the mechanical button) and connected the Q and NOT Q outputs to the anodes of the display. This works fine with Q and NOT Q toggling the LED from red to green every time the button is pressed.
The problem is that there is not enough current from the flip-flop to drive the LED to required brightness even if I leave out current limiting resistors. I tried a switching transistor but the increase was minimal.
Can anyone advise if there’s a way around this? Sorry if I’ve been long-winded.
Thanks in advance.
Trevor
How to increase the voltage/current output from a flip-flop.
I’m using a large 7-segment common anode LED driven from a 7447 decoder/driver. The LED has 2 anodes which are used to switch the LED from red to green with a SPDT switch.
I want to replace the SPDT switch with a push-to-make button (for reasons that seemed good at the time) so I put in a 7453 J-K flip-flop (with a 7414 to debounce the mechanical button) and connected the Q and NOT Q outputs to the anodes of the display. This works fine with Q and NOT Q toggling the LED from red to green every time the button is pressed.
The problem is that there is not enough current from the flip-flop to drive the LED to required brightness even if I leave out current limiting resistors. I tried a switching transistor but the increase was minimal.
Can anyone advise if there’s a way around this? Sorry if I’ve been long-winded.
Thanks in advance.
Trevor