What kind of inverter draws more current at the gates?

"Slurp" a écrit dans le message de news:43649ec8$0$6534$ snipped-for-privacy@ptn-nntp-reader01.plus.net...

which

in

through

could

the

say

of

try using a GTO (Gate turn off) which is a thyristor. they also have both a Scr and Gto combo devices.

Relying on gate input current sounds like an unreliable design methodology.

CMOS types won't take any current worth talking about, so it would be down to TTL. See the data sheets.

Graham

I'm constructing a circuit for source selection on a pre amp using N/O push buttons, so that when a button is pushed it opens the gate of a SCR, which lights an indicator LED and also goes to the gate of a hex inverter (which, in turn goes to the base of a transister and actuates a relay to switch in the input source). I'm limiting the current that can flow through the system, so that when a second button is pushed the current flowing through the first SCR drops below the holding current and it switches off.

To save me wading through datasheets I'm wondering if some kind soul could tell me what kind of inverter draws more current at the gates to help the SCR stay live (TTL, CMOS, Schmitt Triger etc). The specs for the SCRs say they need 2mA to stay conducting and the LEDs only draw 660pA, although I've bench tested the circuit, and it works, just want to make sure.

Thanks Andy

which

in

through

could

the

say

of

DOH!

Sorry SB 660uA (micro)