HEF Datasheet, HEF PDF, HEF Data sheet, HEF manual, HEF pdf, HEF, datenblatt, Electronics HEF, alldatasheet, free. 15 Apr Data sheet acquired from Harris Semiconductor. SCHSC − Revised October HCDB consists of an oscillator section and CMOS Stage Ripple-Carry Binary Counter/Divider and Oscillator. CMOS Stage Ripple-Carry Binary Counter/Divider and Oscillator – CDB. Datasheet.
|Published (Last):||7 July 2005|
|PDF File Size:||17.92 Mb|
|ePub File Size:||14.96 Mb|
|Price:||Free* [*Free Regsitration Required]|
We are only interested in two others, the Hz and the 64Hz outputs, which are used in the display section of the clock. My way of keeping hef4060 datasheet site alive. This not only prevents the clock from advancing every minute during SET mode, it also starts counting a whole new minute once dafasheet clock is set to RUN mode again. The Hef4060 datasheet Counter And now the hours counter. Let’s start simple, the buttons, which are used to set the time. However that hef4060 datasheet require one extra chip for just one gate, whereas I had a spare flip-flop available which could be ab used for the same job.
The oscillator part is built as described in the HEF data sheet. The Q output will be used by the display part of the circuit to suppress the leading 0 of hef4060 datasheet hours counter.
At the end it will produce an accurate frequency of 2Hz on output pin 3. It is spread over two sheets, one sheet covers the time base and the seconds, minutes and hours counters. This will increase the stability of your clock.
This counter is also formed hef4060 datasheet 2 decade counters. Both buttons have a debouncing capacitor in parallel to make sure that every button press results hef4060 datasheet just one pulse. We ehf4060 1Hz, not 2Hz, to feed to our seconds counter.
SB-Projects – Projects – CMOS Clock – Hardware
It’s output Q0 of the first decade hef4060 datasheet IC4A. Hef4060 datasheet is a test point at which you can measure the buffered What is IC3B doing there? This pulse is very short because its cause is removed hef4060 datasheet the reset almost instantly.
Once the counters reach that state they are reset back to 0 again. This will produce a high going reset pulse on the output of IC10B.
In my case the pulse was about ns wide. It also produces several other division ratios. This reset pulse is also used as carry to the hours counter. dataseet
hef40060 Together with hef4060 datasheet knowledge you should be able to build the clock yourself too. This is a nice 0. In Hef4060 datasheet mode the SET hef4060 datasheet is high, and the seconds to minutes carry can never occur because the seconds counter is held in reset. It doesn’t really matter whether we use a rising or falling edge here because this carry pulse is very short. Datxsheet Hardware Part 1 You can download the circuit diagram here. While the clock is in SET mode there won’t come any carry pulses from the minutes counter and that signal is constantly high.
The precision of the resistor datassheet hef4060 datasheet no effect on the precision of the time base B. It’s a bed side table clock, I don’t need it to light up the entire room at night, you know. This helps to tune the frequency of the time base to the correct value.
The Time Hef4060 datasheet IC2 forms the time base oscillator and first pre-scaler stage. It is very important to use 0 tempco capacitor for C4.
The output pulse from IC10A also goes out to the minutes counter, which has to hef4060 datasheet advanced at every overflow of the seconds counter. We’ll have to tell the clock hef4060 datasheet time it is when it has lost all its power anyway.
This page will describe sheet one hef4060 datasheet detail, while the next page will describe datashset number two. But when the most significant digit of the hours counter increments the clock input of the flip-flop rises, which sets the flip-flop, making the Q output hef4060 datasheet.
C5 is used to set the correct frequency.
I don’t need the output of the seconds counter itself, because I do not have a seconds display.