31-07-2012, 11:03 AM
IC 555
[attachment=29625]
Monostable mode:
In this mode, the 555 functions as a "one-shot" pulse generator. Applications include timers, missing pulse detection, bounce free switches, and touch switches, frequency divider, capacitance measurement, pulse-width modulation (PWM) and so on.
Astable:
Free running mode: the 555 can operate as an oscillator. Uses include LED and lamp flashers, pulse generation, logic clocks, tone generation, security alarms, pulse position modulation and so on. Selecting a thermistor as timing resistor allows the use of the 555 in a temperature sensor: the period of the output pulse is determined by the temperature. The use of a microprocessor based circuit can then convert the pulse period to temperature, linearize it and even provide calibration means.
Bistable mode or Schmitt trigger:
The 555 can operate as a flip-flop, if the DIS pin is not connected and no capacitor is used. Uses include bounce-free latched switches.
Specifications:
These specifications apply to the NE555. Other 555 timers can have different specifications depending on the grade (military, medical, etc.).Supply voltage (VCC) 4.5 to 15 V
Supply current (VCC = +5 V) 3 to 6 mA
Supply current (VCC = +15 V) 10 to 15 mA
Output current (maximum) 200 mA
Maximum Power dissipation 600 mW
Power consumption (minimum operating)
Operating temperature 0 to 70 °C
IC 4011
The 4011 is a member of the 4000 Series CMOS range, and contains four independent NAND gates, each with two inputs. The pin out diagram, given on the right, is the standard two-input CMOS logic gate IC layout:
Pin 7 is the negative supply
Pin 14 is the positive supply
Pins 1&2, 5&6, 8&9, 12&13 are gate inputs
Pins 3, 4, 10, 11 are gate outputs
[attachment=29625]
Monostable mode:
In this mode, the 555 functions as a "one-shot" pulse generator. Applications include timers, missing pulse detection, bounce free switches, and touch switches, frequency divider, capacitance measurement, pulse-width modulation (PWM) and so on.
Astable:
Free running mode: the 555 can operate as an oscillator. Uses include LED and lamp flashers, pulse generation, logic clocks, tone generation, security alarms, pulse position modulation and so on. Selecting a thermistor as timing resistor allows the use of the 555 in a temperature sensor: the period of the output pulse is determined by the temperature. The use of a microprocessor based circuit can then convert the pulse period to temperature, linearize it and even provide calibration means.
Bistable mode or Schmitt trigger:
The 555 can operate as a flip-flop, if the DIS pin is not connected and no capacitor is used. Uses include bounce-free latched switches.
Specifications:
These specifications apply to the NE555. Other 555 timers can have different specifications depending on the grade (military, medical, etc.).Supply voltage (VCC) 4.5 to 15 V
Supply current (VCC = +5 V) 3 to 6 mA
Supply current (VCC = +15 V) 10 to 15 mA
Output current (maximum) 200 mA
Maximum Power dissipation 600 mW
Power consumption (minimum operating)
Operating temperature 0 to 70 °C
IC 4011
The 4011 is a member of the 4000 Series CMOS range, and contains four independent NAND gates, each with two inputs. The pin out diagram, given on the right, is the standard two-input CMOS logic gate IC layout:
Pin 7 is the negative supply
Pin 14 is the positive supply
Pins 1&2, 5&6, 8&9, 12&13 are gate inputs
Pins 3, 4, 10, 11 are gate outputs