NIM

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For other meanings, see Nim (disambiguation).

NIM standard module connector pin assignments (required by DOE/ER-0457T)
Pin #	Function	Pin #	Function
1	+3 V	2	-3 V
3	Spare Bus	4	Reserved Bus
5	Coaxial	6	Coaxial
7	Coaxial	8	200 Vdc
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 Vac (hot)	34	Power Return Gnd
35	Reset (scaler)	36	Gate
37	Reset (aux)	38	Coaxial
39	Coaxial	40	Coaxial
41	117 Vac (neutral)	42	High Quality Gnd
G	Gnd Guide Pin

The first (and perhaps the simplest) standard established for nuclear and high energy physics.The Nuclear Instrumentation Module (NIM) standard defines mechanical and electrical specifications for electronics modules used in experimental particle and nuclear physics. First defined by the U.S. Atomic Energy Commission's report TID-20893 in 1968-1969, NIM was most recently revised in 1990 (DOE/ER-0457T).

The concept of modules in electronic systems are analogous to the concept of the objects in Object Oriented Programming or OOP. The use of these concepts in the applications offer enormous advantages in flexibility, interchange of instruments or programs, reduced design effort, ease in updating and maintaining the instruments or programs. A detailed knowledge of the electronics at the level of circuit design or of the coding at the level that is used to write the objects are not necessary in order to set up the system or write a particular application program, only an understanding of the logic will be enough.

The NIM standard provides a common footprint for electronic modules (amplifiers, ADCs, DACs, discriminators, etc.), which plug into a larger chassis (NIM crate, or NIM bin). The crate must supply ±12 and ±24 Volts DC power to the modules via a backplane; the standard also specifies ±6V DC and 220V or 110V AC pins, but not all NIM bins provide them. Mechanically, NIM modules must have a minimum standard width of 1.35 inches (3.43 cm) and a height of 8.75 in (22.225 cm). They can, however, also be built in multiples of this standard, that is, double-width, triple-width etc.^[1]

NIM modules cannot communicate with each other through the crate backplane; this is a feature of later standards such as CAMAC and VMEbus. As a consequence, NIM based ADC modules are nowadays uncommon in nuclear and particle physics. NIM is still widely used for amplifiers, discriminators and other logic modules which do not require digital data communication and benefit from a backplane connector that is also better suited for high power use and allows live plug-in/plug-out.

The NIM standard also specifies cabling, connectors, impedances and levels for logic signals. The fast logic standard (commonly known as NIM logic) is a current based logic, with negative true; an ECL-based logic is also specified.

Apart from the above mentioned mechanical/physical and electrical specifications/restrictions, the individual is free to design his module in any way desired, thus allowing for new developments and improvements for efficiency or looks/aesthetics.