I need to count to nearly 1'000'000 on a counter, can anyone suggest a good counter ? this is for a clock signal generator
You need to provide a bit more information, what are you looking for? A pulse out after the counts or do you need a readout of the counts?
What are you trying to brew this time?
no just a digital counter / frequency divider IC, I'm putting in a 32.768 KHz clock and want to fire an impulse every 30 seconds so make a circuit send an impulse every time the counter resets (or other convenient number occures)
Looking at cost and board space the best solution is probably a PIC10XXX.
74HC160 or 74HC4059 should be usable.
Cascade 6 decade counters...
@thor-arne
you beat me by seconds...
Looking at cost and board space the best solution is probably a PIC10XXX.
Yep. I'm often the last to suggest a microcontroller, but they do make for nice, quick, custom "logic" chips when you need something this specific. I've got a pile of PIC10F200s (both DIP-8 and SOT-23-6 -
holy crap that is a small microcontroller, it's smaller than its 0805 decoupling cap!) that frequently get used for this sort of application. A cascade of 7400 series counters would work, but I'd probably prefer a single 10F200.
A DIP-8 $ 0.30 is hard to beat with 2-4 DIP 16-24 devices...
I had a very quick look at clock divider chips on digikey but you really need a divide and then a multiply to get 30s, which is two chips.
A mcu is going to be cheaper unless you can find a dirt cheap clock logic IC with a half-minute output.
Both 74HC160 and 74HC4059 can be pre-programmed with dip switches, that's why I suggested those.
A micro controller is also usable ofcourse, I just generally don't suggest those if it can be done easily with standard logic.
The MCU gets my vote.
... even if it is a PIC. XD
Could you use a higher frequency crystal with a 4521?
Using standard logic devices a '4060 will divide by 16384, followed by a '4024, '390 or '393 plus gate to divide by 60
how would it work?
32768Hz / 16384 = 2 second clock
2Hz / 60 = 33ms clock
how would it work?
32768Hz / 16384 = 2 second clock
2Hz / 60 = 33ms clock
Having a bad day Psi?
32768Hz / 16384 = 0.5 second
0.5 second / 60 = 30 second
Just saying...
the MCU is out, I'm getting fed up with MCU's at the moment as nothing about C is made simple and when you nearly have your problem solved but for a detail and ask a question on a forum you get told you missed some basic concept and have to go back to learning. Waste of time.
From my school days i seems to remember that I can have a counter that counts to t least what i need and use logic gates to sent out a reset signal at the right count, simples I'll get it done faster with basic digital circuitry than any of the MCU jargons, anythinf complex i'll take to an arduino, sad i know but as it is only with arduino that everything is made easy for idiots like me that is the route i will have to take.
My main concern is that I remeber something about counters not being sycronous and drifting due to propagation delays as one flip/flop clocked another, that is my main concern. What about the HCF4060M013TR ? it has built in oscillator circuitry
A brief search at Farnell led to the SN74LV8154N which can be used as a 32 bit counter (you need 20 bits I guess). It is a dual 16bit but can be connected as one 32bit. They only seem to have the SMD version in stock. You might need a 4 input AND gate (or 3 x 2 input AND gates) to detect when it reaches 0xF0000 and use that as both a reset and the clock (I may be out by one on this but the error of 1 part in a million is probably worth living with to simplify the circuit).
the MCU is out, I'm getting fed up with MCU's at the moment as nothing about C is made simple
Then I guess my suggestion of PIC10F200 is
way the hell out! With 384 bytes ROM and 16 bytes RAM, I don't think you'd have much luck programming it in anything but assembly.
I can definitely understand the draw of discrete logic chips. I use them a lot and love them. Sorry I can't help much with this specific problem though, if you want to use discrete logic - digital timing isn't exactly my forte.
A brief search at Farnell led to the SN74LV8154N which can be used as a 32 bit counter (you need 20 bits I guess). It is a dual 16bit but can be connected as one 32bit. They only seem to have the SMD version in stock. You might need a 4 input AND gate (or 3 x 2 input AND gates) to detect when it reaches 0xF0000 and use that as both a reset and the clock (I may be out by one on this but the error of 1 part in a million is probably worth living with to simplify the circuit).
so long as it does not have ripple type drift problems. I don't mind a slightly more complicated logic gate array to detect the overflow.
the MCU is out, I'm getting fed up with MCU's at the moment as nothing about C is made simple and when you nearly have your problem solved but for a detail and ask a question on a forum you get told you missed some basic concept and have to go back to learning. Waste of time.
Sounds like you need to put in some time to learn how to write (C or asm) code. The real waste of time happens when you refuse to learn.
What about the HCF4060M013TR ? it has built in oscillator circuitry
I've never been a fan of the 4060. A better discrete chip for large counts is the
MC14541B. It has 2^8, 2^10, 2^13, and 2^16 outputs, with the built-in oscillator circuitry, and pin controls for auto-reset and output logic level - plus it's not a ripple counter like the 4060 - and has a smaller pin count.
Combine this with any Divide-by-N 4-bit counter (like the MC14526B) and you can easily have precision 30 second pulses from 32kHz - done completely with synchronous counters - and without the need for any extra gates.
So do I need to specifically look for a synchronized counter to make sure it does not drift off timing due to propagation delays ?