Decoder chip with +Vcc outputs

[Whimsy]

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.

 

[rjenkinsgb]

You could use two 74HCT237E ICs; they are 3 to 8 decoders with active high outputs and both high and low enables.

https://uk.farnell.com/texas-instruments/cd74hc237e/logic-decoder-demux-hs-3-8-16dip/dp/3119876

https://www.ti.com/lit/ds/symlink/cd74hc137.pdf?ts=1595445268853&ref_url=https%253A%252F%252Fwww.google.co.uk%252F

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":

https://www.ti.com/lit/ds/symlink/uln2803a.pdf?ts=1595445531591&ref_url=https%253A%252F%252Fwww.google.co.uk%252F

 

[Whimsy]

I followed the links provided, and they both look promising as solutions to my problem. Thanks rjenkinsgb!

 

[eTech]

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 can use a CD4514B followed by a TBD62003A mosfet array driver.

 

[gophert]

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).

 

[eTech]

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.

 

[eTech]

A TBD63783A will provide a source output if the load is connected to ground.

 

[eTech]

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).

See post #7