Short Nuclear Instrumentation Crate - side view

The Nuclear Instrumentation Module (NIM) standard defines mechanical and electrical specifications for electronics modules used in experimental

particle In the Outline of physical science, physical sciences, a particle (or corpuscule in older texts) is a small wikt:local, localized physical body, object which can be described by several physical property, physical or chemical property, chemical ...

and

nuclear Nuclear may refer to: Physics Relating to the nucleus of the atom: * Nuclear engineering *Nuclear physics *Nuclear power *Nuclear reactor *Nuclear weapon *Nuclear medicine *Radiation therapy *Nuclear warfare Mathematics *Nuclear space *Nuclear ...

physics. The concept of

module Module, modular and modularity may refer to the concept of modularity. They may also refer to: Computing and engineering * Modular design, the engineering discipline of designing complex devices using separately designed sub-components * Mo ...

s in

electronic Electronic may refer to: *Electronics, the science of how to control electric energy in semiconductor * ''Electronics'' (magazine), a defunct American trade journal *Electronic storage, the storage of data using an electronic device *Electronic co ...

systems offers enormous advantages in flexibility, interchange of instruments, reduced design effort, ease in updating and maintaining the instruments. The NIM standard is one of the first (and perhaps the simplest) such standard. First defined by the

U.S. Atomic Energy Commission The United States Atomic Energy Commission (AEC) was an agency of the United States government established after World War II by U.S. Congress to foster and control the peacetime development of atomic science and technology. President ...

's report TID-20893 in 1968–1969, NIM was most recently revised in 1990 (DOE/ER-0457T). It provides a common footprint for electronic modules (amplifiers,

ADC ADC may refer to: Science and medicine * ADC (gene), a human gene * AIDS dementia complex, neurological disorder associated with HIV and AIDS * Allyl diglycol carbonate or CR-39, a polymer * Antibody-drug conjugate, a type of anticancer treatm ...

s, DACs, discriminators, etc.), which plug into a larger chassis ( NIM crate, or NIM bin). The crate must supply ±12 and ±24

volt The volt (symbol: V) is the unit of electric potential, electric potential difference (voltage), and electromotive force in the International System of Units (SI). It is named after the Italian physicist Alessandro Volta (1745–1827). Defi ...

s DC power to the modules via a

backplane A backplane (or "backplane system") is a group of electrical connectors in parallel with each other, so that each pin of each connector is linked to the same relative pin of all the other connectors, forming a computer bus. It is used as a back ...

; the standard also specifies ±6 V DC and 220 V or 110 V AC pins, but not all NIM bins provide them. Mechanically, NIM modules must have a minimum standard width of 1.35 in (34 mm), a maximum faceplate height of 8.7 in (221 mm) and depth of 9.7 in (246 mm). They can, however, also be built in multiples of this standard width, that is, double-width, triple-width etc.W. R. Leo, ''Techniques for Nuclear and Particle Physics Experiments - A How-to Approach''. 1994 The NIM standard also specifies cabling, connectors, impedances and levels for

logic Logic is the study of correct reasoning. It includes both formal and informal logic. Formal logic is the science of deductively valid inferences or of logical truths. It is a formal science investigating how conclusions follow from premises ...

signals. The fast logic standard (commonly known as NIM logic) is a current-based logic, negative "true" (at −16 mA into 50 ohms = −0.8 volts) and 0 mA for "false"; an ECL-based logic is also specified. Apart from the above mentioned mechanical/physical and electrical specifications/restrictions, the individual is free to design their module in any way desired, thus allowing for new developments and improvements for efficiency or looks/aesthetics. NIM modules cannot communicate with each other through the crate backplane; this is a feature of later standards such as CAMAC and

VMEbus VMEbus (Versa Module Europa or Versa Module Eurocard bus) is a computer bus standard, originally developed for the Motorola 68000 line of CPUs, but later widely used for many applications and standardized by the IEC as ANSI/IEEE 1014-1987. I ...

. As a consequence, NIM-based ADC modules are nowadays uncommon in nuclear and particle physics. NIM is still widely used for amplifiers, discriminators, nuclear pulse generators and other logic modules that do not require digital data communication but benefit from a backplane connector that is better suited for high power use.

Standard Pin Assignments

{, class="wikitable" , + NIM standard module connector pin assignments (required by DOE/ER-0457T) ! Pin # !! Function !! Pin # !! Function , - , 1 , , Reserved 3 V, 2 , , Reserved ��3 V, - , 3 , , Spare bus , 4 , , Reserved bus , - , 5 , , Coaxial , 6 , , Coaxial , - , 7 , , Coaxial , 8 , , 200 V DC , - , 9 , , Spare , 10 , , +6 V , - , 11 , , −6 V , 12 , , Reserved bus , - , 13 , , Spare , 14 , , Spare , - , 15 , , Reserved , 16 , , +12 V , - , 17 , , −12 V , 18 , , Spare bus , - , 19 , , Reserved bus , 20 , , Spare , - , 21 , , Spare , 22 , , Reserved , - , 23 , , Reserved , 24 , , Reserved , - , 25 , , Reserved , 26 , , Spare , - , 27 , , Spare , 28 , , +24 V , - , 29 , , −24 V , 30 , , Spare bus , - , 31 , , Spare , 32 , , Spare , - , 33 , , 117 V AC (hot) , 34 , , Power return Gnd , - , 35 , , Reset (scaler) , 36 , , Gate , - , 37 , , Reset (aux) , 38 , , Coaxial , - , 39 , , Coaxial , 40 , , Coaxial , - , 41 , , 117 V AC (neutral) , 42 , , High-quality Gnd , - , G , , Gnd guide pin , , , ,

References

Experimental particle physics

Standard Pin Assignments

See also

References