Category: Science

1N4001 , Why is the diode so called?


The 1Nxxxx numbering system is an American standard (now adopted globally) used to mark semiconductor devices. The “1N” means that it is a single junction semiconductor device (i.e. a diode). “4001” is a number given to the smallest diode in the 400x series (4001, 4002, and so on) – the number indicates the voltage, current and power ratings of the diode. A transistor (which has 2 junctions) would be numbered 2Nxxxx.

1-single junction semiconductor device N-Silicon device 400-its a particular series whose max allowed current is 1A. x- it denotes the voltage rating. 1-50V,2-100V,3-200V… 7-1000V.

SO, it is called 1N4001.



The objective of the circuit is to build an electronic dice based on the functions of a 555 timer integrated circuit that operates in the astable mode.

  • LM555 – a highly stable device for generating accurate oscillation or time delays with additional terminals provided for resetting or triggering, used in linear ramp generator, pulse position and width modulation, time delay & pulse generation, sequential &precision; timing, with features such as adjustable duty cycle, temperature stability, TTL compatible output, availability in 9-pin MSOP package, timing from microseconds, and operates in both astable & monostable modes
  • 4017 – a decade counter where the count advances as the clock input becomes high that may be combined with diodes for some functions such as flash sequences
  • BC550 – an NPN general purpose transistor with low current and low voltage used for low noise stages in audio frequency equipment

The 555 IC is a highly stable device for generating oscillation or accurate time delays used in pulse width/position modulation, sequential timing, time delay generation, linear ramp generator, precision timing, and pulse generation due to its features such as normally open and normally off output, temperature stability, output and supply TTL compatible, adjustable duty cycle, and operates in both astable and monostable mode.