• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

A slightly higher output voltage from a PIC

Status
Not open for further replies.

Richard S

New Member
I want to switch a chip (low current) which requires an off signal of under 4.5v, and an on signal of over 5.5v. I need to do this for eight pins.

The first thing I thought of was an ULN2803 with pullup resistors, but that takes up a lot of room, and makes the board very complex. Are there any chips which will do this without the use of pullup resistors? I would like a chip with 8 switchers in it, which eliminates MOSFET drivers etc (although these seem like a waste as it is low speed, low current).

Any ideas of chips?

Summary:
Input: 8 TTL inputs
Output: 8 low/high outputs, high being close to VCC.

There is 9V and 5V power rails currently.

Many thanks!

Richard
 

Electronworks

New Member
Unless I have missed something, what is wrong with powering an octal changeover analogue switch off the 9V rail and switching the logic inputs with your micro? Connect one side of the switch to your 9V, one side to ground and the common to the device you need to drive. Not sure if you can get octal changeovers, but 2 quads should be easy to get. take a look at Maxim or TI..:D
 

Richard S

New Member
That sounds like the solution - I just need to find one. Anyone got any suggestion (pref. Maxim)?

The device I want to control is two 4066s, running on 9v (so needing 5.5v for a logic 1).

Richard
 

Richard S

New Member
I've chosen:

I'm going to go with MAX474-something. They are the same as the 4066, but can be driven directly from a PIC (1.8v is logic high).

Thanks for everyone's help!

Richard
 
Last edited:
Status
Not open for further replies.

Latest threads

EE World Online Articles

Loading
Top