Texas Instruments 74LS Logic – Signal Switches, Multiplexers, Decoders parts available at DigiKey. The SN74LS, 1-of Decoder/Driver, is designed to accept. BCD inputs and provide appropriate outputs to drive digit incandescent displays. All outputs. 74LS, 74LS Datasheet, 74LS BCD to Decimal Decoder Datasheet, buy 74LS
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That’s why it may not seem an optimal approach.
You can skip the bipolar alltogether, and connect your pull-up directly to 12V. Hi Folks Just looking at a driver design based on the 74LS Quoth josephfeng at This cannot be undone. Your email is included with the abuse report.
Been racking my brains over this for days now and just can’t work out whether this is the case or not. The gates of the HV drivers 74ls1145 be connected to collectors of the bipolars.
Since the outputs of the LS are active low when selected, and the FET gate is active high, the transistor as you show it in your picture gives the inversion you need.
I would then have bipolar NPN transistors with the collectors connected to 12V via resistors. If the 74LS will sink enough current, I think you should be able to meet your needs with a cascode stage, and this will only require one transistor and maybe one resistor per output. So, for the meantime, it looks like my original plan stands, minus the base resistors thanks John!
74LS145 – BCD to Decimal Decoder/Driver
What you don’t need is the series R2 since the base current has to go through R1 and not the LS output. Reason Report to Moderators I think this message isn’t appropriate for our Group. I amy have misundertood you completely, but I think there is a much simpler solution. This is certainly a technique to apply for other applications I have a LOT to learn in the analogue fieldbut I think that we would have the same issue that John pointed out – the control signals are inverted and still need to be flipped before they get to the output device.
Whilst I could use other components, this is very much a “spares box” project – to build exclusively with what I have on 74ls14. Subject of the new topic: If that hasn’t confused you already, here’s a schematic of what I’m trying 7l4s145 describe: If you want to used the FET, substitute the source for the emitter, the gate for the base, and the drain for the collector.
The 74LS datasheet I’ve got here suggests that the outputs are ” The Group moderators are responsible for maintaining their community and can address these issues.
Do I need to put an inverters between the 74LS and the bipolars?
74LS Datasheet(PDF) – Motorola, Inc
Search Only Within This Topic. The new topic will begin with this message. That makes my life much easier, although I will have to check on the manufacturer of the devices that I have to make sure that they have the higher voltage tolerance. Are you sure you wish to delete this message from the 74lss145 archives of neonixie-l groups.
74LS145 – 1-of-10 Dcdr Drvr Open Coll
Quoth Christian Bjelle at Thanks for your help on this guys! I assume that this means that I connect the outputs to my logic VCC via resistors. The bases of the bipolars would be connected to the 47ls145 of the 74LS via resistors.