You need to handle these carefully, things may have changed, but they used to be horribly static-sensitive.
That's another very good point.
Any CMOS IC's should come in some static protected packaging such as conductive foam or in a conductive tube etc. Before you handle the device, if possible try and touch something that is grounded to discharge any static on your person. Location and climate plays a big part in this with dry conditions and low humidity being the danger signs.
I think most devices have protection diodes on the inputs but they are not foolproof. When you fit a device, solder the power pins first and then the others.
Any CMOS IC's should come in some static protected packaging such as conductive foam or in a conductive tube etc. Before you handle the device, if possible try and touch something that is grounded to discharge any static on your person. Location and climate plays a big part in this with dry conditions and low humidity being the danger signs.
I think most devices have protection diodes on the inputs but they are not foolproof. When you fit a device, solder the power pins first and then the others.
Sorry for the delay in reply, last days were quite busy.
@ RMJ1, thanks for pointing this out, indeed, I'm quite new to this type of electronics.
I will place the small CAP over the supply and GND of the chip.
Good to know that the standard version will work. Have made an order for the
C4011 Quad 2 inp NAND Gate DIP14
The circuit will be used in home audio, is static also still a risk when installed? Or is this Ok when a ground lead is connected.
Maybe good to solder these devices with a GND connected?
@ RMJ1, thanks for pointing this out, indeed, I'm quite new to this type of electronics.
I will place the small CAP over the supply and GND of the chip.
Good to know that the standard version will work. Have made an order for the
C4011 Quad 2 inp NAND Gate DIP14
The circuit will be used in home audio, is static also still a risk when installed? Or is this Ok when a ground lead is connected.
Maybe good to solder these devices with a GND connected?
Static is no problem once its installed. Remember no input must be left floating, they must be tied either high, low, or if more convenient to board layout to an adjacent output pin of another gate.
For soldering and working with CMOS a grounded iron is essential really. My technique would be to be sat down (so not moving about generating static) and then to touch momentarily a grounded object to dissipate any static on me. Even placing your hand on a wall for a second or two will will do the same. Then solder the chip in. If your iron isn't grounded then unplug it and then solder it in whilst its still hot.
(CMOS isn't as bad to work with as it might appear but better to be safe than sorry)
For soldering and working with CMOS a grounded iron is essential really. My technique would be to be sat down (so not moving about generating static) and then to touch momentarily a grounded object to dissipate any static on me. Even placing your hand on a wall for a second or two will will do the same. Then solder the chip in. If your iron isn't grounded then unplug it and then solder it in whilst its still hot.
(CMOS isn't as bad to work with as it might appear but better to be safe than sorry)
Ok, thanks for the tips, will check if my iron is grounded.
It sounds a little bit scary, but indeed, better be safe than sorry.
In the circuit all gates are used, so floating should not be a problem at all.
Was just googling some data sheets and found the TC4467. This is a high current (and also costly) device. Would something like this limit the risk on a not saturated transistor?
It sounds a little bit scary
, but indeed, better be safe than sorry.In the circuit all gates are used, so floating should not be a problem at all.
Was just googling some data sheets and found the TC4467. This is a high current (and also costly) device. Would something like this limit the risk on a not saturated transistor?
You will have no problem fully turning on the transistor with a 4011.
The static issue is really common sense... when you think that walking on a man made carpet in low humidity can charge you up to perhaps 10 or 15kV (15 thousand volts) and you then discharge that through your finger into a semicondutor that has layers a few microns thick internally... well you see the problem.
Static damage is only a problem when it actually happens to you Many use CMOS and take no precautions at all and get away with it. A few seconds thought guarantees you wont have a problem.
The static issue is really common sense... when you think that walking on a man made carpet in low humidity can charge you up to perhaps 10 or 15kV (15 thousand volts) and you then discharge that through your finger into a semicondutor that has layers a few microns thick internally... well you see the problem.
Static damage is only a problem when it actually happens to you
Many use CMOS and take no precautions at all and get away with it. A few seconds thought guarantees you wont have a problem.Indeed, static discharge can be quite intense and high voltage. I did draw occasionally a large spark from my volume knob... In the winter now I always touch the ground of my wall outlet first.
I intend to build it first on a bread board, will make a good lead to gnd with it.
I just ordered the 4011, I also found a .1uf ceramic cap. Difficult to find until I searched in the multi layer section of the supplier I use.
In the winter now I always touch the ground of my wall outlet first.I intend to build it first on a bread board, will make a good lead to gnd with it.
I just ordered the 4011, I also found a .1uf ceramic cap. Difficult to find until I searched in the multi layer section of the supplier I use.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.