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RS-232 is a standard built a longer while ago, and its specifications dictate a maximum voltage of +-25V. HIGH signal levels at +-5V, +-12V and +-15V are not uncommon. The range of operation is from -25V to +25V. Also, RS-232 standard notes that levels between -3V and +3V are illegal (as in, they are assumed not to exist, nor carry any information).
On the other hand, TTL stands for Transistor-Transistor Logic, and the maximum rating for that is 5V. HIGH signal levels are at any point above 3.5V. The range of operation is between 0V and 5V.
If one were to connect these with no conversion, the TTL device would probably be burned. Even if it would withstand, the designs are sufficiently different for them not to communicate properly. Thus, the need to 'bridge the gap' between the two.
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What is a TTL-compatible output?
Compatibility in TTL means that the output of one TTL device can be used to drive the Input of the other TTL device , This because the low and high output window fit inside the low and high input window/profile TTL stand for Transistor Transistor Logic, so any voltage between 0 and 5 volt is compatible where any voltage between 3V and 5V is logic 1 and zero volt is logic 0
Which has a shorter propagation delay TTL or CMOS?
TTL
What is voltage of TTL circuit?
CMOS gate circuits have input and output signal specifications that are quite different from TTL. For a CMOS gate operating at a power supply voltage of 5 volts, the acceptable input signal voltages range from 0 volts to 1.5 volts for a "low" logic state, and 3.5 volts to 5 volts for a "high" logic state. "Acceptable" output signal voltages (voltage levels guaranteed by the gate manufacturer over a specified range of load conditions) range from 0 volts to 0.05 volts for a "low" logic state, and 4.95 volts to 5 volts for a "high" logic state:It should be obvious from these figures that CMOS gate circuits have far greater noise margins than TTL: 1.45 volts for CMOS low-level and high-level margins, versus a maximum of 0.7 volts for TTL. In other words, CMOS circuits can tolerate over twice the amount of superimposed "noise" voltage on their input lines before signal interpretation errors will result.CMOS noise margins widen even further with higher operating voltages. Unlike TTL, which is restricted to a power supply voltage of 5 volts, CMOS may be powered by voltages as high as 15 volts (some CMOS circuits as high as 18 volts). Shown here are the acceptable "high" and "low" states, for both input and output, of CMOS integrated circuits operating at 10 volts and 15 volts, respectively:The margins for acceptable "high" and "low" signals may be greater than what is shown in the previous illustrations. What is shown represents "worst-case" input signal performance, based on manufacturer's specifications. In practice, it may be found that a gate circuit will tolerate "high" signals of considerably less voltage and "low" signals of considerably greater voltage than those specified here.Conversely, the extremely small output margins shown -- guaranteeing output states for "high" and "low" signals to within 0.05 volts of the power supply "rails" -- are optimistic. Such "solid" output voltage levels will be true only for conditions of minimum loading. If the gate is sourcing or sinking substantial current to a load, the output voltage will not be able to maintain these optimum levels, due to internal channel resistance of the gate's final output MOSFETs.Within the "uncertain" range for any gate input, there will be some point of demarcation dividing the gate's actual "low" input signal range from its actual "high" input signal range. That is, somewhere between the lowest "high" signal voltage level and the highest "low" signal voltage level guaranteed by the gate manufacturer, there is a threshold voltage at which the gate willactuallyswitch its interpretation of a signal from "low" or "high" or vice versa. For most gate circuits, this unspecified voltage is a single point:
Ttl nand gate?
The TTL Nand gate is usually used in the design of various electric circuits.
Can DTL logic work with TTL logic?
Yes, standard 5V powered DTL and TTL devices are fully input/output logic level and fanout compatible. However DTL chips are nearly impossible to find today. The only thing to be careful about is old DTL based designs often used wired-and gates (i.e. directly tying outputs of several gates together to reduce part count). You cannot do this with normal TTL!
Why ttl voltage level converting to rs232 level?
Whwn an IC is connected to a PC, then the voltage levels of these two should be synchronized. For this purpose, the TTL voltage level is converted to RS 232 level. RS 232 is the interface between a PC and an IC.
Why do you connect capacitor in MAX232?
The input to the max232 ic will be of Transistor Transistor Logic (TTL) and its voltage range will be of 5 volt. The output of the max 232 ic will be of Recomended Standard 232 Logic (RS232 logic) and its voltage range will be of 12 volt. The max 232 ic which is operating on 5 volt supply has to step up the 5 volt input to 12 volt. Hence a capacitor is used for pumping the voltage and called as pumping capacitor.
What is 232 in RS232 and MAX232?
The difference between max232 and rs232 is the voltage levels of the rs232 are high. In order to reduce those voltage means to convert those voltage levels to TTL logic levels we use max232 integrated chip which is a dual driver/ receiver.
What is conversion of TTl voltage level to MOS level?
A: TTL Vcc is fixed at 5v +/- .5 volts while MOS can be run at higher Vcc like 12 volts therefore there is a compatibility problem and a converter must be installed between this family of gates to make them compatible with each other. So a converter will do just that translate a TTL level to a MOS level
What is voltage level of ttl?
Standard TTL (which stands for Transistor-Transistor Logic) circuits operate on a 5V power supply. The typical level for a logical "0" is between 0V and 0.8V, and the typical level for a logal "1" is somewhere between 2.2V and 5V. Typically, a value little lower than Vcc (power source voltage) is used; in case of a 5V supply, this is usually around 4.5V, but TTL devices are built to withstand full Vcc as input, just in case.
What TTL Logic Voltage Level?
Historically, transistor-transistor logic (TTL) voltage levels have been 5.0 volts, with a high being any voltage above about 3.5 volts and a low being any voltage below about 1.5 volts, with lots of variations on the high/low cutoffs from part to part. Since about 2001, however, most processors have been using low-voltage TTL (LVTTL), which has a nominal voltage of 3.3 volts (approx >2.2 volts for high and approx < 1.2 volts for low). Hence, many parts advertised as "TTL" today actually work at 3.3 volts rather than 5.0 volts.
Full form of vcc and vdd in TTL and CMOS?
vcc-voltage collector to collector vdd- voltage deran to deran ttl- transister transister logic cmos - complementary metal oxide same conductor
What is the maximum supply voltage for a 74LS08?
The maximum supply voltage per the data sheet is 5.25 volts. This is a common max for TTL type IC's.
What is a TTL-compatible output?
Compatibility in TTL means that the output of one TTL device can be used to drive the Input of the other TTL device , This because the low and high output window fit inside the low and high input window/profile TTL stand for Transistor Transistor Logic, so any voltage between 0 and 5 volt is compatible where any voltage between 3V and 5V is logic 1 and zero volt is logic 0
What is a TTL compatible output?
A: TTL gates operates on the premise of having +5 dc on the rail therefore the output will be in the range +5 volts. A cmos gate while similar to a TTL function is not really compatible since the output volts can be 12 volts or more. Besides that TTL gates require some input current for it to operate
What is the difference between ULN2803 and ULN2804?
ULN2802 ULN2803 ULN2804A 8 NPN Darlington transistors, connected in arrays ideal for logic interface level digital circuits (eg TTL, CMOS or PMOS/NMOS) and higher current/voltage such as lamps, solenoids, relays, print Hammers or other similar loads, a wide range of uses: computer, industrial and consumer applications. All device functions are transiently suppressed by collector output and clamping diodes. The ULN2803 is designed for standard TTL compliance, while the ULN2804 is manufactured to fit 6 to 15V on high-level CMOS or PMOS. The circuit is a reverse output type, that is when a low-level voltage is an input, the output terminal can be turned on to work. For more, The ULN2803 and ULN2804 have the same pinout and current parameters. But there is a little difference. The drive voltage of ULN2803 is 5V for TTL and CMOS circuits. The driving voltage of ULN2804 is 6V-15V for CMOS and PMOS circuits. Reference: The Overview of ULN2804A [FAQ] [ utmel]
Interfacing of ttl with cmos and cmos with ttl?
whis is Endurance mors or ttl
