3.3v logic to 5v logic

what is the best chip to use to convert 3.3v logic to 5v logic

only need one direction!
iv got 16 io lines so some sort of octal chip would be nice
needs to supply at least 15ma ish per output as well

really after some sort of level converting line driver buffer

thanks :slight_smile:

Which direction are you going? 3V3 to 5V or 5V to 3V3?

3.3 > 5v :slight_smile:

(3.3 from a LPC microcontroller)

check this http://www.sparkfun.com/products/8745,but you can use a simple npn transistor with a clam diode in the base

ah i saw this.

im after some sort of of octal version as im a bit pushed for space and need 16 lines so want some sort of 8/16 line package :slight_smile:

must be surface mount! :slight_smile:

russdx:
3.3 > 5v :slight_smile:

(3.3 from a LPC microcontroller)

Okay, so that's more cryptic than what you said before. Can you use words this time?

3.3 from a LPC to what?

If you want the outputs of a 3V3 device to connect to the inputs of a 5V device, no shift is probably necessary. The high threshold of the 5V device is probably low enough to detect a high for 3V3 logic.

A 74HC14 maybe?

i did some similar using normal TTL gate and no problem, i used a normal SN7414 with no problem,but i used only 4 of the 6 available , maybe you have to use one with less consumption like the SN74HTC14 in SO14 package

As James said, you don't need a converter from 3V3 logic to 5V logic.
(I myself use the 3V3 FTDI breakout to upload sketches to 5V Arduinos, and never had a communication problem.)

How about this?

Octal part, TTL input, +/- 24mA output to TTL.

you can also use this one...

sorry 3.3 to LPC actually means: 3.3v from a LPC2106 microcontroller IO :slight_smile:

im trying to interface to a HT1632C LED driver chip and it says its IO is 5v

my code wasn't working so i just assumed it was a logic level fault. but i tried my code on a arduino as well (deffo 5v logic) and it still dint work. so its prob not logic level lol

thanks for the suggestions :slight_smile:

problem is most likely my buggy code and not the voltage levels.

but i did come across this http://uk.rs-online.com/web/p/level-translator/0510617/

looks pretty cool :slight_smile:

EDIT - the above chip needs external resistors on the 5v side :frowning:

but this looks really good :slight_smile:
http://docs-europe.electrocomponents.com/webdocs/0e7e/0900766b80e7e0bc.pdf

was my bad programming not the logic levels to blame hehe

i will add the above chip to my design though to be safe :slight_smile: