Method for naming semiconductor device type in China
The semiconductor device model is composed of five parts (field effect device, semiconductor special device, composite tube, PIN tube, laser device name only third, four or five parts). The five part is as follows:
Part I: digital representation of the effective number of electrodes in a semiconductor device. 2- diode, 3- transistor.
The second part: the material and the polarity of the semiconductor device with the Chinese phonetic alphabet. When the diode is expressed: A-N type germanium material, B-P type germanium material, C-N type silicon material, D-P type silicon material. When the transistor is said: A-PNP type germanium material, B-NPN type germanium material, C-PNP type silicon material, D-NPN type silicon material.
In the third part, the inner form of the semiconductor device is represented by the Chinese phonetic alphabet. P- tube and V- microwave tube, W- regulator, C- tube, Z- parameter rectifier, L- rectifier stack, S- pipe, N- pipe, tunnel damping U- optoelectronic devices, K- switch, X- low frequency power tube (F<3MHz, Pc<1W), G- high frequency low power tube (f>3MHz, Pc<1W), low frequency D- highpowervalve (f< 3MHz, Pc>1W A-), high frequency and high power tube (f>3MHz, Pc>1W), T- (thyristor controlled rectifier), Y- effect device, avalanche transistor B- and J- step recovery tube, CS- FET, BT- semiconductor devices, special FH- composite pipe, PIN-PIN pipe, JG- laser device.
The fourth part: the number of serial number.
The fifth part: the specification number of the phonetic alphabet of the Chinese phonetic alphabet.
For example: 3DG18 said NPN type silicon material high frequency transistor.
Japanese semiconductor discrete device type designation method. Two, the Japanese production of semiconductor discrete devices, from five to seven parts. Usually only to the first five parts, the symbols of each part are as follows:
The first part: the number or type of effective electrode. 0- (Ji Guangmin) combined photoelectric diode transistor and the device, 1- diode, triode tube with 2 or two other PN node devices, 3- has four effective electrode or with three PN nodes, all of all other devices and so on.
The second part: the Japanese electronics industry association JEIA registration mark. S- says semiconductor discrete devices that have been registered in the Japanese electronics industry association JEIA.
The third part: using the letter to indicate the polarity and type of the material. A-PNP type high frequency tube, B-PNP tube, C-NPN tube type high frequency and low frequency, low frequency D-NPN pipe, F-P control thyristor, G-N control thyristor, H-N base single transistor and J-P channel fet, K-N channel field-effect tube, M- triac.
The fourth part: the digital representation in the order number of the Japanese electronics industry association JEIA registration. Integer - more than two from "11", said the sequence number registered in the electronic industry association of Japan JEIA; the same device performance of different companies can use the same sequence number; the larger the number, the more recent products.
The fifth part: the letter of the same model of the improved product logo. A, B, C, D, E, F said that the device is the prototype of the product improvement.
American semiconductor discrete device model nomenclature.
Three, the United States, the name of the transistor or other semiconductor devices is more chaotic. The electronic industry association of the United States, the name of the semiconductor discrete devices are as follows:
The first part: the type of the use of symbols. JAN-, JANTX-, JANTXV- special corps Corps corps, super JANS-, space level (no) - non military supplies.
In the second part, the number of PN nodes is represented by numbers. 1- diode, 2= transistor, PN three 3- junction devices, PN N-N junction devices.
The third part: the United States Electronic Industry Association (EIA) registered mark. N- the device has been registered in the United States Electronic Industry Association (EIA).
The fourth part: the registration sequence number of the American electronics industry association. Number of digits - the device in the order number of the American Electronics Industry Association.
The fifth part: using the letter to indicate the component file. A, B, C levels, D, all of all - the same type of devices don‘t. Such as: JAN2N3251A PNP silicon high-frequency switching power transistor, JAN- transistor, N-EIA 2- grade, 3251-EIA registered marks, registration number, A-2N3251A.
Four, the International Federation of electronic semiconductor device model name method
Germany, France, Italy, Holland, Belgium and other European countries, Hungary, Romania, Yugoslavia, Poland and other Eastern European countries, most of the will of type designation for discrete semiconductor devices and electronic international. This naming method consists of four basic parts, each part of the symbol and meaning as follows:
Part 1: materials used in the use of letters. The A- device uses materials such as germanium, the band gap Eg=0.6~1.0eV B- devices using materials such as silicon and Eg=1.0~1.3eV C- devices using Eg>1.3eV materials such as gallium arsenide, D- devices using materials such as InSb Eg<0.6eV, E- device using composite material and light battery.
The second part: the type and the main features of the device. A- detection switch diode mixer, B- varactor, C- low frequency power transistor, D- low frequency power transistor, E- tunnel diodes, F- high frequency low power transistor, G- composite device and other devices, H- magneto diode and K- open magnetic circuit Holzer element, L- high frequency power transistor, M- Holzer in the closed magnetic circuit element, P- sensitive devices, Q- devices, R- small power thyristor, S- power switch, T- power thyristor, U- power switch tube, X- double diode, rectifier diode, zener diode Z- Y-.
In the third part, the registration number is represented by numbers or letters. Three digits - represents the registration number of general semiconductor devices, a letter plus two digits - the number of registered serial number of special semiconductor devices.
The fourth part: using the letter of the same type of device to divide the file. A, B, C, D, E all - all said the same type of device for mark grading according to a parameter.
In addition to the four basic parts, and sometimes with a suffix, in order to distinguish the characteristics or further classification. Common suffix is as follows:
1, voltage regulator diode model suffix. The first part of the suffix is a letter, said the range of allowable error stable voltage, A, B, C, letter D, E said the allowable error is + 1%, + 2%, + 5%, + 10% and + 15% respectively; the second part is the suffix number, an integer representing the nominal voltage numerical stability; the third part is the suffix letter V, on behalf of the decimal point, after the letter V as digital voltage regulator tube nominal voltage stability small value.
2, the rectifier diode suffix is digital, said the device is the maximum reverse peak voltage value, the unit is volts.
3, the number of the suffix is also a number, usually marked with the maximum reverse peak voltage value and the maximum reverse turn off voltage in the value of the smaller value of the voltage.
Such as: NPN said BDX51- silicon low frequency high power transistors, AF239S- said PNP germanium high frequency small power transistors.
Five, the European early semiconductor discrete device model nomenclature
Some European countries, such as Germany and Holland, adopt the following naming methods.
Part 1: O- representation of semiconductor devices.
Second part: A- diode, C- transistor, AP- photodiode, CP- photoelectric transistor, AZ- voltage regulator tube, RP- photoelectric device.
The third part: multi bit digital representation device

(a), semiconductor diode parameter symbols and their significance
CT--- barrier capacitance
Cj--- (inter) capacitor, said in the set at both ends of the diode bias, the total capacitance of germanium detector diode
Cjv--- bias junction capacitance
Co--- zero bias capacitance
Cjo--- zero bias junction capacitance
Cjo/Cjn--- junction capacitance variation
Cs--- tube shell capacitor or package capacitor
Ct--- total capacitance
CTV--- voltage temperature coefficient. Under the test current, the relative change of the stable voltage and the absolute change of the ambient temperature.
CTC--- capacitance temperature coefficient
Cvn--- nominal capacitance
IF--- forward direct current (positive test current). Germanium detector diode in the forward voltage under the VF regulations, through the current between the electrodes; silicon rectifiers, silicon stack in the use of the prescribed conditions, the maximum current through the half wave sine allows continuous in (average), silicon switching diode allows the positive DC current through the current under rated power; given the measurement of electrical parameters when the positive voltage regulator diode
IF (AV) - positive average current
IFM (IM) --- positive peak current (positive maximum current). Under the rated power, the maximum forward current of the diode is allowed. Light emitting diode limit current.
IH--- constant current, maintain current.
Ii--- light emitting diode
IFRM--- positive repetitive peak current
IFSM--- positive non repetitive peak current (surge current)
Io--- rectifier current. The operating current of the specified frequency and specified voltage conditions.
IF (OV) - positive overload current
IL--- optical current or constant current diode current limit
ID--- dark current
Base modulation current in IB2--- single junction transistor
IEM--- emitter peak current
IEB10--- double pole unijunction transistor emitter in reverse with the first base current
IEB20--- double pole unijunction tube emitter to current
ICM--- maximum output average current
IFMP--- forward pulse current
IP--- peak current
IV--- valley current
IGT--- thyristor control pole trigger current
IGD--- thyristor control pole without triggering current
IGFM--- control positive peak current
IR (AV) --- reverse average current
IR (In) --- reverse current (reverse leakage current). In the measurement and reverse characteristics, reverse current is given; silicon stack in half sine wave resistive load circuit, reverse voltage set value, the current through the current through the switch; silicon diode with reverse voltage VR; zener diode in reverse voltage, leakage current of the rectifier tube leakage; in the current half sine wave maximum reverse voltage.
IRM--- reverse peak current
IRR--- thyristor reverse repetitive average current
Average repetitive current of IDR--- thyristor
IRRM--- reverse repetitive peak current
IRSM--- reverse non repetitive peak current (reverse surge current)
Irp--- reverse recovery current
Iz--- stable voltage and current (reverse current). When the reverse electric parameters are tested, the reverse current is given.
Izk--- voltage regulator tube knee point current
IOM--- maximum forward (rectifier) current. Under specified conditions, the maximum instantaneous current can withstand; maximum allowable working current through the germanium detector diodes in continuous sinusoidal resistive load half wave rectifier circuit
IZSM--- voltage regulator diode surge current
IZM--- maximum voltage current. Voltage regulator diode allows current through the maximum dissipation power
IF--- positive total instantaneous current
IR--- reverse total instantaneous current
Ir--- reverse recovery current
Iop--- operating current
Is--- constant current diode current
F--- frequency
N--- capacitance change index; capacitance ratio
Q--- optimal value (quality factor)
Delta vz--- voltage regulator tube voltage drift
Critical rise rate of di/dt--- on state current
Critical rise rate of dv/dt--- on state voltage
PB--- withstand pulse burning power
PFT (AV) - positive conduction average power dissipation
PFTM--- forward peak power dissipation
PFT--- forward general instantaneous dissipated power
Pd--- dissipation power
PG--- gate average power
PGM--- gate peak power
PC--- control of a very average power or collector dissipation power
Pi--- input power
PK--- maximum switching power
PM--- rated power. Silicon diode junction temperature is not higher than 150 degrees can withstand the maximum power
PMP--- maximum leakage power
PMS--- maximum withstand pulse power
Po--- output power
PR--- reverse surge power
Total power dissipation of Ptot---
Pomax--- maximum output power
Psc--- continuous output power
PSM--- non repetitive surge power
PZM--- maximum power dissipation. Under given conditions of use, the voltage regulator diode is allowed to withstand the maximum power
RF (R) - positive differential resistance. In forward conduction, the current increases with the increase of the voltage index, and presents the obvious nonlinear characteristics. In a positive voltage, the voltage increases small quantity of V, forward current increased Delta I, Delta V/, Delta I differential resistance
Base resistance of RBB--- dual base transistor
RE--- RF resistance
RL--- load resistance
Rs (RS) - series resistance
Rth---- thermal resistance
R (th) ja---- junction to ambient thermal resistance
Rz (RU) - dynamic resistance
R (th) jc--- junction to the thermal resistance of the shell
R Delta - attenuation resistance
R (th) - transient resistance
Ta--- ambient temperature
Tc--- shell temperature
Td--- delay time
Tf--- fall time
Tfr--- forward recovery time
Tg--- circuit switching off time
Tgt--- gate control gate opening time
Tj--- junction temperature
Tjm--- maximum junction temperature
Ton--- opening time
Toff--- turn off time
Tr--- rise time
Trr--- reverse recovery time
Ts--- storage time
Storage temperature of tstg--- Temperature Compensation Diode
A--- temperature coefficient
Peak wavelength of p---
Delta lambda - spectral half width
ETA - single transistor divider ratio or efficiency
VB--- reverse peak breakdown voltage
Vc--- rectifier input voltage
VB2B1--- base voltage
VBE10--- emitter and first base reverse voltage
VEB--- saturation pressure drop
VFM--- maximum forward voltage drop (positive peak voltage)
VF--- forward voltage drop (positive DC voltage)
The VF--- forward voltage difference
VDRM--- off state repetitive peak voltage
VGT--- gate trigger voltage
VGD--- gate voltage
VGFM--- gate positive peak voltage
VGRM--- gate reverse peak voltage
VF (AV) - positive average voltage
Vo--- AC input voltage
VOM--- maximum output average voltage
Vop--- operating voltage
Vn--- center voltage
Vp--- peak point voltage
VR--- reverse working voltage (reverse DC voltage)
VRM--- reverse peak voltage (maximum test voltage)
V (BR) --- breakdown voltage
Vth--- valve voltage (threshold voltage)
VRRM--- reverse repetitive peak voltage (reverse surge voltage)
VRWM--- reverse peak voltage
V--- V valley point voltage
Vz--- stable voltage
A Vz--- voltage range voltage increment
Vs--- (leading to a voltage signal voltage or current) tube current and voltage stability
Av--- voltage temperature coefficient
Vk--- knee point voltage (current diode)
VL --- limit voltage

(two) bipolar transistor parameter symbols and their significance
Cc--- collector capacitance
Ccb--- collector and base capacitance
Cce--- emitter output capacitance
Ci--- input capacitance
Cib--- common base input capacitance
Cie--- common emitter input capacitance
Cies--- common emitter short circuit input capacitance
Cieo--- common emitter open input capacitance
Cn--- and capacitor (external circuit parameters)
Co--- output capacitance
Cob--- common base output capacitance. In the base circuit, the output capacitance between the collector and the base.
Coe--- common emitter output capacitance
Coeo--- common emitter open circuit output capacitance
Cre--- common emitter feedback capacitance
Cic--- collector junction barrier capacitance
CL--- load capacitance (external circuit parameters)
Cp--- shunt capacitors (external circuit parameters)
BVcbo--- emitter open circuit, collector to base breakdown voltage
BVceo--- base open circuit, CE junction breakdown voltage
BVebo--- open collector EB junction breakdown voltage
BVces--- base and emitter short circuit CE junction breakdown voltage
Cer--- BV base and emitter series resistance, CE junction breakdown voltage
D--- duty cycle
FT--- characteristic frequency
Fmax--- maximum oscillation frequency. Operating frequency when the power gain of the transistor is equal to 1
HFE--- common emitter static current amplification factor
HIE--- common emitter static input impedance
HOE--- common emitter static output conductance
RE--- h common emitter static voltage feedback coefficient
Hie--- common emitter minimum signal short circuit input impedance
The open circuit voltage feedback coefficient of hre--- total emission minimum signal
Hfe--- common emitter minimum signal short circuit voltage amplification factor
Hoe--- total emission minimum signal open circuit output admittance
Average value of IB--- base DC current or AC current
Average value of Ic--- collector DC current or AC current
Average value of IE--- emitter DC current or AC current
Icbo--- base, emitter to ground open circuit, in the specified VCB reverse voltage conditions between the collector and the base of the reverse cut-off current
Iceo--- emitter, base on open circuit, in the specified reverse voltage VCE conditions, between the collector and emitter reverse current
Iebo--- base, collector to ground open circuit, in the specified reverse voltage VEB conditions, the emitter and the base between the reverse cut-off current
Icer--- between the base and the emitter of the series resistance R, collector and emitter voltage between VCE for the specified value, the collector and emitter reverse between the current
Ices--- emitter, base to ground short circuit, in the specified reverse voltage VCE conditions, between the collector and emitter reverse current
The Icex--- emitter is grounded, and the base and emitter are added with a specified bias voltage, and the reverse current between the collector and the emitter is at a specified reverse bias voltage VCE.
Maximum average value of ICM--- collector to maximum allowable current or AC current.
IBM--- in the collector allows the range of power dissipation, the maximum value of the DC current of the base can be continuously through the maximum, or the maximum average value of the AC current
ICMP--- collector maximum allowable pulse current
ISB--- two breakdown current
IAGC--- forward automatic control current
Pc--- collector dissipation power
PCM--- collector maximum allowable power dissipation
Pi--- input power
Po--- output power
Posc--- oscillation power
Pn--- noise power
Total power dissipation of Ptot---
ESB--- two breakdown energy
RBB ‘- base extension resistance (base region intrinsic resistance)
RBB ‘Cc--- base collector time constant, which is the product of the base expansion resistance and the capacitance of the collector junction
Rie--- emitter ground, AC output short circuit input resistance
The output resistance of the AC input circuit of VCE, roe---, Ic, or IE, is measured at the specified, frequency, and frequency.
RE--- external emitter resistance (external circuit parameters)
RB--- external base resistance (external circuit parameters)
Rc --- external collector resistance (external circuit parameters)
RBE--- external base emitter resistance (external circuit parameters)
RL--- load resistance (external circuit parameters)
RG--- signal source resistance
Rth--- thermal resistance
Ta--- ambient temperature
Tc--- tube shell temperature
Ts--- junction temperature
Tjm--- maximum allowable junction temperature
Tstg--- storage temperature
Td---- delay time
Tr--- rise time
Ts--- storage time
Tf--- fall time
Ton--- opening time
Toff--- turn off time
VCB--- collector to base (DC) voltage
VCE--- collector emitter (DC) voltage
VBE--- base emitter (DC) voltage
VCBO--- base ground, emitter to ground open circuit, the highest voltage between collector and base is under specified condition
VEBO--- base, open collector to ground, emitter and base in the specified conditions under the maximum pressure
VCEO--- emitter, base to ground open, collector and emitter under specified conditions of the maximum pressure
VCER--- emitter, the base and the emitter of the series resistance R, the collector and emitter in the specified conditions of the maximum pressure
VCES--- emitter, base to ground short circuit, collector and emitter under specified conditions of the maximum pressure
The VCEX--- emitter is grounded, and the base and the emitter are provided with a specified bias voltage, and the maximum pressure resistance between the collector and the emitter is under specified conditions.
Vp--- through voltage.
VSB--- two breakdown voltage
VBB--- base (DC) supply voltage (external circuit parameters)
Vcc--- collector (DC) supply voltage (external circuit parameters)
VEE--- emitter (DC) supply voltage (external circuit parameters)
VCE (SAT) - emitter ground, under the conditions of Ic, IB Collector Emitter Saturation Voltage Drop
VBE (SAT) --- emitter, under specified conditions of Ic, IB, base emitter saturation voltage drop (forward voltage drop)
VAGC--- forward automatic gain control voltage
Vn (P-P) - input - equivalent noise voltage peak
N--- V noise voltage
Cj--- (inter) capacitor, said in the set at both ends of the diode bias, the total capacitance of germanium detector diode
Cjv--- bias junction capacitance
Co--- zero bias capacitance
Cjo--- zero bias junction capacitance
Cjo/Cjn--- junction capacitance variation
Cs--- tube shell capacitor or package capacitor
Ct--- total capacitance
CTV--- voltage temperature coefficient. Under the test current, the relative change of the stable voltage and the absolute change of the ambient temperature.
CTC--- capacitance temperature coefficient
Cvn--- nominal capacitance
IF--- forward direct current (positive test current). Germanium detector diode in the forward voltage under the VF regulations, through the current between the electrodes; silicon rectifiers, silicon stack in the use of the prescribed conditions, the maximum current through the half wave sine allows continuous in (average), silicon switching diode allows the positive DC current through the current under rated power; given the measurement of electrical parameters when the positive voltage regulator diode
IF (AV) - positive average current
IFM (IM) --- positive peak current (positive maximum current). Under the rated power, the maximum forward current of the diode is allowed. Light emitting diode limit current.
IH--- constant current, maintain current.
Ii--- light emitting diode
IFRM--- positive repetitive peak current
IFSM--- positive non repetitive peak current (surge current)
Io--- rectifier current. The operating current of the specified frequency and specified voltage conditions.
IF (OV) - positive overload current
IL--- optical current or constant current diode current limit
ID--- dark current
Base modulation current in IB2--- single junction transistor
IEM--- emitter peak current
IEB10--- double pole unijunction transistor emitter in reverse with the first base current
IEB20--- double pole unijunction tube emitter to current
ICM--- maximum output average current
IFMP--- forward pulse current
IP--- peak current
IV--- valley current
IGT--- thyristor control pole trigger current
IGD--- thyristor control pole without triggering current
IGFM--- control positive peak current
IR (AV) --- reverse average current
IR (In) --- reverse current (reverse leakage current). In the measurement and reverse characteristics, reverse current is given; silicon stack in half sine wave resistive load circuit, reverse voltage set value, the current through the current through the switch; silicon diode with reverse voltage VR; zener diode in reverse voltage, leakage current of the rectifier tube leakage; in the current half sine wave maximum reverse voltage.
IRM--- reverse peak current
IRR--- thyristor reverse repetitive average current
Average repetitive current of IDR--- thyristor
IRRM--- reverse repetitive peak current
IRSM--- reverse non repetitive peak current (reverse surge current)
Irp--- reverse recovery current
Iz--- stable voltage and current (reverse current). When the reverse electric parameters are tested, the reverse current is given.
Izk--- voltage regulator tube knee point current
IOM--- maximum forward (rectifier) current. Under specified conditions, the maximum instantaneous current can withstand; maximum allowable working current through the germanium detector diodes in continuous sinusoidal resistive load half wave rectifier circuit
IZSM--- voltage regulator diode surge current
IZM--- maximum voltage current. Voltage regulator diode allows current through the maximum dissipation power
IF--- positive total instantaneous current
IR--- reverse total instantaneous current
Ir--- reverse recovery current
Iop--- operating current
Is--- constant current diode current
F--- frequency
N--- capacitance change index; capacitance ratio
Q--- optimal value (quality factor)
Delta vz--- voltage regulator tube voltage drift
Critical rise rate of di/dt--- on state current
Critical rise rate of dv/dt--- on state voltage
PB--- withstand pulse burning power
PFT (AV) - positive conduction average power dissipation
PFTM--- forward peak power dissipation
PFT--- forward general instantaneous dissipated power
Pd--- dissipation power
PG--- gate average power
PGM--- gate peak power
PC--- control of a very average power or collector dissipation power
Pi--- input power
PK--- maximum switching power
PM--- rated power. Silicon diode junction temperature is not higher than 150 degrees can withstand the maximum power
PMP--- maximum leakage power
PMS--- maximum withstand pulse power
Po--- output power
PR--- reverse surge power
Total power dissipation of Ptot---
Pomax--- maximum output power
Psc--- continuous output power
PSM--- non repetitive surge power
PZM--- maximum power dissipation. Under given conditions of use, the voltage regulator diode is allowed to withstand the maximum power
RF (R) - positive differential resistance. In forward conduction, the current increases with the increase of the voltage index, and presents the obvious nonlinear characteristics. In a positive voltage, the voltage increases small quantity of V, forward current increased Delta I, Delta V/, Delta I differential resistance
Base resistance of RBB--- dual base transistor
RE--- RF resistance
RL--- load resistance
Rs (RS) - series resistance
Rth---- thermal resistance
R (th) ja---- junction to ambient thermal resistance
Rz (RU) - dynamic resistance
R (th) jc--- junction to the thermal resistance of the shell
R Delta - attenuation resistance
R (th) - transient resistance
Ta--- ambient temperature
Tc--- shell temperature
Td--- delay time
Tf--- fall time
Tfr--- forward recovery time
Tg--- circuit switching off time
Tgt--- gate control gate opening time
Tj--- junction temperature
Tjm--- maximum junction temperature
Ton--- opening time
Toff--- turn off time
Tr--- rise time
Trr--- reverse recovery time
Ts--- storage time
Storage temperature of tstg--- Temperature Compensation Diode
A--- temperature coefficient
Peak wavelength of p---
Delta lambda - spectral half width
ETA - single transistor divider ratio or efficiency
VB--- reverse peak breakdown voltage
Vc--- rectifier input voltage
VB2B1--- base voltage
VBE10--- emitter and first base reverse voltage
VEB--- saturation pressure drop
VFM--- maximum forward voltage drop (positive peak voltage)
VF--- forward voltage drop (positive DC voltage)
The VF--- forward voltage difference
VDRM--- off state repetitive peak voltage
VGT--- gate trigger voltage
VGD--- gate voltage
VGFM--- gate positive peak voltage
VGRM--- gate reverse peak voltage
VF (AV) - positive average voltage
Vo--- AC input voltage
VOM--- maximum output average voltage
Vop--- operating voltage
Vn--- center voltage
Vp--- peak point voltage
VR--- reverse working voltage (reverse DC voltage)
VRM--- reverse peak voltage (maximum test voltage)
V (BR) --- breakdown voltage
Vth--- valve voltage (threshold voltage)
VRRM--- reverse repetitive peak voltage (reverse surge voltage)
VRWM--- reverse peak voltage
V--- V valley point voltage
Vz--- stable voltage
A Vz--- voltage range voltage increment
Vs--- (leading to a voltage signal voltage or current) tube current and voltage stability
Av--- voltage temperature coefficient
Vk--- knee point voltage (current diode)
VL --- limit voltage

(three) the symbolic significance of the field effect transistor parameters
Cds--- drain source capacitance
Cdu--- drain substrate capacitance
Cgd--- gate source capacitance
Cgs--- drain source capacitance
Ciss--- grid short circuit common source input capacitance
Coss--- grid short circuit common source output capacitance
Crss--- grid short circuit common source reverse transmission capacitor
D--- duty cycle (duty factor, external circuit parameter)
Di/dt--- current rising rate (external circuit parameters)
Dv/dt--- voltage rise rate (external circuit parameters)
ID--- drain current (DC)
IDM--- drain pulse current
ID (on) - - state drain current
IDQ--- quiescent drain current (RF power tube)
IDS--- drain current
IDSM--- maximum leakage current
IDSS--- gate - source short circuit, drain current
IDS (SAT) - channel saturation current (drain source saturation current)
IG--- gate current (DC)
IGF--- forward gate current
IGR--- reverse gate current
When the IGDO--- source is open, the gate current is cut off.
IGSO--- open drain, cutoff gate current
IGM--- gate pulse current
IGP--- peak current
IF--- diode forward current
IGSS--- off grid current
IDSS1--- the saturation current of the first pipe drain source
IDSS2--- the saturation current of second pipe leakage source
Iu--- substrate current
Ipr--- current pulse peak (external circuit parameters)
Gfs--- positive transconductance
Gp--- power gain
Gps--- common source and high frequency power gain
GpG--- common gate and high frequency power gain
GPD--- common drain and high frequency power gain
Ggd--- gate leakage conductance
Gds--- drain source conductance
K--- offset voltage temperature coefficient
Ku--- transfer coefficient
L--- load inductance (external circuit parameters)
LD--- drain inductance
Ls--- source inductor
RDS--- drain source resistance
RDS (on) --- drain source on state resistance
RDS (of) --- leakage source fault state resistance
RGD--- gate leakage resistance
RGS--- gate source resistance
Rg--- gate external resistance (external circuit parameters)
RL--- load resistance (external circuit parameters)
R (th) jc--- crust resistance
R (th) ja--- junction ring thermal resistance
PD--- drain dissipation power
PDM--- drain maximum allowable power dissipation
PIN-- input power
POUT--- output power
PPK--- pulse power peak (external circuit parameters)
To (on) --- opening delay time
TD (off) --- off delay time
Ti--- rise time
Ton--- opening time
Toff--- turn off time
Tf--- fall time
Trr--- reverse recovery time
Tj--- junction temperature
Tjm--- maximum allowable junction temperature
Ta--- ambient temperature
Tc--- tube shell temperature
Tstg--- storage temperature
VDS--- drain source voltage (DC)
VGS--- gate source voltage (DC)
VGSF-- forward gate source voltage (DC)
VGSR--- reverse gate source voltage (DC)
VDD--- drain (DC) supply voltage (external circuit parameters)
VGG--- gate (DC) power supply voltage (external circuit parameters)
Vss--- source (DC) supply voltage (external circuit parameters)
VGS (th) --- open voltage or valve voltage
V (BR) DSS--- drain source breakdown voltage
Gate source breakdown voltage of V (BR) GSS--- drain source
VDS (on) --- drain source voltage
VDS (SAT) --- drain saturation voltage
VGD--- gate drain voltage (DC)
Vsu--- source substrate voltage (DC)
VDu--- drain substrate voltage (DC)
VGu--- gate substrate voltage (DC)
Zo--- driver source resistance
ETA - drain efficiency (RF power transistor)
Vn--- noise voltage
AID--- drain current temperature coefficient
Ards--- drain source resistance temperature coefficient