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Most technologies are limited to VGS < 10 V, or 5 V in more modern ones, and need circuits like this. High voltage level shifters are needed in high voltage DC/DC converters and similar circuits. The general approach is to create a rail that is ~ 5 V below the HV supply and use this to limit the VGS of the high side FETs. You also don't drive the 10 pF ...


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The usual technique is to use a cross-coupled level shifter. If you use "your favourite search engine" you gets scads of images. This one is grabbed from Freescale Although you will notice that the PMOS here has gates that are subjected to the full voltage swing. Having done this before I am wondering if your statement about Vgs is true. This might be ...


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You'd leave out the compensation capacitor etc. and you have to make sure your front end topology will tolerate high differential voltage (many op-amps cannot - they may have something like back-to-back diodes across the input with some series resistance). Also, for many applications, offset voltage and gain is not as importance as speed, so those ...


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The main difference is that opamps need to be stable when in a negative feedback configuration. This means that they need to be compensated. Compensation slows your slew rate. For comparators stability is not such a big problem. All you need to ensure is that it saturates and doesn't oscillate. Comparators also have two output states. This means that gates ...


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Here is the NOR that is probably being referred to: In the state where both C&D signals are high both of the lower NMOS transistors are on and thus discharge the "Out" node faster than a single NMOS could (in the case of when only one of C or D is high). Basically you don't worry about it, because there are other more dominant effects. And to fully ...


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In such a case you have to consider the worst case, i.e. only one transistor active in the pull down network and of course you have to account for the series connection of two PMOS transistors in the pull up network. The design should use the inverter as reference for the worst case, so that you have equal delays. Of course for some transitions the gate ...


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You can regard both types as complementary, if the circuits are identical but one is just the "upside down" version of the other, everything applies to both architectures you only need to watch the directions of currents and voltage polarties but that is it. Lastly, what is the difference between these two architectures?(in general) They are identical but ...


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You can play around with making gates from transistors using the CD4007 chip. It contains two complimentary pairs plus an inverter. Some possible gates with one package: The other thing that might be useful is a CD4016 quad transmission gate. With those two you could make just about anything, in theory. In practice, it would be very tedious to make ...


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Inside the inverter there is a switch, this switch flips between Voh and Vol. Now, this switch has resistance (like pretty much everything) and so when you pull more current, the switch isn't able to pull the output as close to Vcc or GND as it would have been able to other wise. Basically, Voh drops and Vol rises (assuming equal loads in both directions)


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The voltage divider created by the totem pole output and the loads causes VOH to drop below VDD. If this voltage drops below VIH before the current reaches IOH then the digital circuit may glitch. If IOH is reached before VIH then the totem pole output may be damaged. Neither is a good outcome which is why one or more buffers may be needed if the load count ...



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