Wiring instructions for HEF4894B

I've purchased a few 12-bit shift registers (HEF4894B) for a project. I've found many references on how to hook up and cascade 8-bit shift registers (the 74HC595), but nothing so far on the HEF4894B. The pins listed in the data sheet are a little different from the 74HC595, so I'm looking for a reference or tutorial on how to hook up and cascade a few HEF4894B to an Arduino.

Thanks,

Jeff

Hi Jeff and welcome.

As you have already found out, there probably isn't a tutorial out there for this chip. It's just not very common in Arduino circles. If you compare the data sheet for the chip with the NXP data sheet for the '595, it should be simple enough to figure out which pins are equivalent. Note that the '595 has a couple of pins with no equivalent on the '4894. You can manage without those.

I can forsee 2 problems: 1. The shiftOut and SPI.transfer functions normally used to send data to one or more chained '595s send data 8 bits at a time but the '4894 needs 12. There are ways to deal with this. 2. I think the '4894 may only be available as a surface mount component. Do you have experience soldering these? How will you prototype your circuit?

Paul

the DIP version shows to have the same power rating as their 595 DIP version. 750mW for the package vs 500mW for the SMT versions

digikey wants $3.93 for the DIP

the TPIC6B595 is high power and about half the cost the HC595 is less than 70 cents

although it seems like a nice chip, the costs are pretty high.

it does offer an opportunity to the Arduino world. with all the confusing 'tutorials' for the 595, it offers a clean slate for a clear and understandable tutorial for a shift register !

@PaulRB

If you compare the data sheet for the chip with the NXP data sheet for the '595, it should be simple enough to figure out which pins are equivalent. Note that the '595 has a couple of pins with no equivalent on the '4894. You can manage without those.

For reference, here is the link to the datasheet for the HEF4894B: http://www.nxp.com/documents/data_sheet/HEF4894B.pdf

...and here's a tutorial on the 74HC595 which I've used in the past (it has a clear explanation of the pins and how to wire up to an Arduino Uno): http://bildr.org/2011/02/74hc595/

(it sounds like you have a knowledgeable understanding of both chips, but I thought I'd list my references for anyone else who happens to come across this thread)

Here is my confusion: The 74HC595 has: serial input register clock serial clock serial clear

...and on the other hand the HEF4894B has: serial input (check) clock input (I'm assuming it's the same/equivalent to the serial clock on the 74HC595) two serial outputs strobe input

...so I have some confusion as to how to wire up a HEF4894B into an Arduino Uno.

  1. I think the '4894 may only be available as a surface mount component.

It's available both in SMD and through hole: http://www.digikey.com/product-search/en?x=0&y=0&lang=en&site=us&KeyWords=HEF4894B

(and I bought the through hole kind)

Thanks,

Jeff

@dave-in-nj

although it seems like a nice chip, the costs are pretty high.

I need to shift 10 bits (for a 10 LED bar graph, and want to be able to chain them). I couldn't find any 10-bit shift registers, only 8-bit, 12-bit, and 16-bit shift registers. I know I could use two 74HC595s, but that would yield 16 bits and I wanted to try designing a circuit around a 12-bit shift register. Maybe it might be easier to use two 74HC595s or a single 16-bit shift register.

it does offer an opportunity to the Arduino world. with all the confusing 'tutorials' for the 595, it offers a clean slate for a clear and understandable tutorial for a shift register !

That crossed my mind. After I'm all done, and if I can't find any good tutorials I was thinking about writing a tutorial of my own.

Thanks,

Jeff

"Two serial outputs": I think one is the 12th led driver pin (sink only, constant current) and the other is a regular ttl logic output for chaining to the input of the next register.

"Strobe input" equivalent to register clock I think.

You would hope that if a single manufacturer like nxp made both chips, they would standardise the terminology they use in their data sheets. But no...

You found thru-hole chips, so no problems with soldering!