Decoder chip with +Vcc outputs

Whimsy

New Member
I am working with a 4 to 16 decoder chip whose outputs are V- when active. This device is driving a 5V spst relay, and I am using a PNP transistor to convert V- to V+. This works, but is proving to be problematic, thus I am looking for a simpler more elegant solution. Perhaps there exits a decoder whose outputs are V+ when active, or alternatively you could suggest an IC that contains multiple PNP transistors that will eliminate the use of discreet components, resistors, and wires, and a lot of soldering.
 
You could use two 74HCT237E ICs; they are 3 to 8 decoders with active high outputs and both high and low enables.

Connect the fourth input to the low enable to get outputs 0-7 on one IC and the high enable on the other for outputs 8-15.

You can use a couple of octal darlington driver ICs to connect those with the relays, eg. ULN2803; they even include the "flywheel diodes":
 

You can use a CD4514B followed by a TBD62003A mosfet array driver.
 
You can use a CD4514B followed by a TBD62003A mosfet array driver.
That will help to drive a higher current load but it won't help if his load is connected to ground and needs high side Supply (Vcc).
 
That will help to drive a higher current load but it won't help if his load is connected to ground and needs high side Supply (Vcc).

I didn't bother to check that but neither will a ULN2803.
 
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A TBD63783A will provide a source output if the load is connected to ground.
 
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