Hello.
I have a circuit setup using a tlc5940 through hex invertors to switch logic level mosfets.
I have recently been looking at introducing decoupling capacitance to smooth out the circuit.
Is it really necessary if the load is minimal.
What would be the best type of capacitor. Can I use a minimal standard electrolytic one.?
Is there a specific place they must be installed. I'm thinking possibly best between the suplly to each TLC chip of hex invertor.
Thanks
Matt
All 5V logic chips should have 0.1 uF ceramic or tantalum caps as close to the power pins as physically possible (< 1 cm). This originated with TTL logic of the 70s and has continued ever since. CMOS don't reqyire it but the TLC5940 might benefit from it. You should understand that a cjip thst sinks current like the TLC5940 is not giung to need the same kind of decoupling as a TTL gate. It probably needs a 100uF to 220uF filter cap on the 5V bus more than it needs 0.1 uF decoupling caps.
CMOS chips most certainly do need decoupling capacitors.
Do not use tantalum caps for decoupling, they are expensive, not as effective and a fire hazard when placed across a supply.
Great thanks.
I have a large selection on electrolytic capacitors. From small to the real huge ones.
So looks like I can use them.