Skill/references/description_format.md

Description format (Vecmocon Altium Library SOP)

This is the authoritative rule for the Description field the skill writes into a part's workbook. It has two layers:

1. The four formats derived from the SOP — Resistor, Capacitor, Zener, TVS — from Engineering Data Management — SOP: Component Naming, Mandatory Parameters, and Design Item ID Format (§6). Follow these parameter orders strictly. The prefix, however, is the house Class_TYPEID form (see below), which supersedes the SOP's own prefix tokens.
2. A house extension that carries the same basis to every other type in the library (all 125 type-IDs / 18 classes), so no component is left without a Description convention. These are built on the SOP pattern and are the working standard; when a specific part doesn't fit cleanly, follow the pattern and confirm the token order with the engineer rather than inventing something off-pattern.

The basis (applies to every component)

The Description is not a free-form sentence. It is a single string of _-joined tokens in this shape:

Class_TYPEID_param1_param2_..._Package_[AECQ-XXX]

• Class_TYPEID — the mandatory opening two tokens of every Description, always. This replaces the old technology prefixes (CHIP_RES, ELE_CAP, TANT_CAP, NMOS, …) — those are retired and must not be used. Examples: Diode_TVS_…, Capacitor_TAN_…, Resistor_FIX_…, Transistor_MOS_….
  • Class — spelled exactly as the library-repo folder name, so a Description's first token always matches the folder the part lives in. Take it from CLASS_FOLDER in scripts/common.py (the authoritative map) — e.g. Diode, Capacitor, Resistor, Transistor, IC, Protection, Inductor_Magnetics, Relay_Contactor, Switch_Button, Antenna_RF, Crystal_Oscillator, Battery_Cell, Audible_Indicator, Display_HMI, Sensor, Thermal_Cooling, Connector. Mixed case as written — do not upper-case it. Note Inductor_Magnetics and friends already contain an _; that is expected and correct. The one Class whose folder name contains spaces, Power Conversion Module, is written Power_Conversion_Module in a Description.
  • TYPEID — the Type ID from references/taxonomy.md, always upper-case, exactly as the template sheet names it (TVS, TAN, CER, FIX, MOS, SCH, LDO, …). This is the same typeid used in the part tag MPN_make_typeid, so the three agree.
  • Get both from the taxonomy for the typeid you classified the part to in step 2 — never invent or abbreviate either token.
• params — the part's defining ratings, in the fixed order given for that class. Read them off the datasheet. If the datasheet is silent on a required token, leave it out and flag it — an honest gap beats a guessed value.
• Package — the IPC/industry package or case code, near the end (0402, SOD-323, SOIC-8, LQFP-48, SMD,D6.3xL5.8mm, …).
• AECQ-XXX — only when the datasheet states automotive qualification (AECQ-200, AECQ-101, AECQ-100); it is always the last token. Omit entirely if not stated — never assume qualification.

Description ≠ Design Item ID ≠ Comment — three different fields that share notation but not content: Description is the strict string here (SOP §6); Design Item ID (SOP §2) is a shorter procurement id (RES_36kΩ_±0.1%_0402) that keeps its own SOP notation and does not take the Class_TYPEID prefix — use it only as a guide to token vocabulary, never put it in the Description column; Comment (SOP §4) is always the exact MPN.

Notation conventions (from the SOP examples)

• Value / unit with SOP casing: 36kΩ, 2.2uF, 600Ω, 48MHz, 10uH. Use Ω for ohms; uF/nF/pF, uH/nH/mH, Hz/kHz/MHz, F for farads (supercaps). A range uses ~ (3.5V~28V, 5.2V~5.6V).
• Power 62.2mW, 500mW, 344W; voltage 100v, 25V; current 0.25A, 250mA.
• Tolerance signed percent ±0.1%, ±10%.
• Temperature coefficient (ceramics) lower-case dielectric class: x7r, c0g, x5r.
• Keep tokens in the same style throughout so descriptions sort and read consistently.

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Layer 1 — the four SOP-derived formats (parameter order is strict)

The parameter orders below are the SOP's and are not up for reinterpretation. The prefix is the house Class_TYPEID form, which replaces the SOP §6 prefix tokens.

Resistor

Resistor_TYPEID_Value_Wattage_Tolerance_Package_AECQ-XXX(optional)

Example: Resistor_FIX_36kΩ_62.2mW_±0.1%_0402 (was CHIP_RES_36kΩ_62.2mW_±0.1%_0402)

Capacitor

Capacitor_TYPEID_Value_Voltage_Tolerance_Package_TemperatureCoefficient_AECQ-XXX(optional)

Example: Capacitor_CER_2.2uF_100v_±10%_1210_x7r (was CHIP_CAP_2.2uF_100v_±10%_1210_x7r)

Zener diode

Diode_ZEN_VoltageZener(Vz)_Power_Package_AECQ-XXX(optional)

TVS diode

Diode_TVS_VoltageBreakdown(Vbr)_VoltageClamping(Vc)_Current(Ip)_Package_AECQ-XXX(optional)

House prefix note: SOP §6 wrote the diodes as DIO-Z / DIO-T and the R/C formats with technology prefixes (CHIP_RES, CHIP_CAP). Vecmocon has standardised on Class_TYPEID for every component, so all four of these now open with Resistor_ / Capacitor_ / Diode_ plus the typeid. This is a deliberate house override of SOP §6's prefix; the parameter order (Vz+Power for Zener; Vbr+Vc+Ip for TVS; etc.) remains exactly the SOP's.

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Layer 2 — house extension, every other type (same basis)

Each class below gives its parameter order (the tokens between prefix and package) and the per-type prefix. Package is always the second-to-last token; optional AECQ-XXX is last.

Resistor (RES family) — Resistor_TYPEID_Value_Power_Tolerance_Package_[AECQ]

Type	Prefix	Notes
FIX Thick-film chip	Resistor_FIX	SOP example; the strict format above
TFR Thin-film chip	Resistor_TFR	precision/low-tempco; may append tempco (ppm)
MFR Metal-film	Resistor_MFR
CFR Carbon-film	Resistor_CFR
MOR Metal-oxide	Resistor_MOR	high-power leaded
WWR Wirewound	Resistor_WWR	low-ohm/high-power
SHT Current-sense/shunt	Resistor_SHT	value in mΩ (e.g. 2mΩ), power token is the sense power
ARR Array/network	Resistor_ARR	add element count/config, e.g. 4x, before value
POT Potentiometer/trimmer	Resistor_POT	Resistor_POT_Value_Taper_Power_Package (taper LIN/LOG)
FSR Fusible/safety	Resistor_FSR
NTC thermistor	Resistor_NTC	Resistor_NTC_R25_Beta_Tolerance_Package (R25 e.g. 10kΩ, Beta e.g. B3950)
PTC thermistor	Resistor_PTC	Resistor_PTC_R25_Package (or trip current/temp if that's the rated spec)

Example: Resistor_SHT_2mΩ_1W_±1%_2512 · Resistor_NTC_10kΩ_B3950_±1%_0402

Capacitor (CAP family) — Capacitor_TYPEID_Value_Voltage_Tolerance_Package_[Dielectric]_[AECQ]

Type	Prefix	Notes
CER Ceramic MLCC	Capacitor_CER	SOP; dielectric token (x7r/c0g…) required
ELE Aluminium electrolytic	Capacitor_ELE	tolerance often omitted; case like SMD,D6.3xL5.8mm
TAN Tantalum	Capacitor_TAN
PLY Aluminium-polymer	Capacitor_PLY	low-ESR; ESR may follow voltage
FLM Film (MKT/MKP)	Capacitor_FLM
SFY Safety Class-X/Y	Capacitor_SFY	add safety class token (X2/Y1) after value
SUP Supercapacitor/EDLC	Capacitor_SUP	value in farads, e.g. 1F; add ESR if rated

Example: Capacitor_ELE_33uF_25V_SMD,D6.3xL5.8mm · Capacitor_SUP_1F_5.5V_RADIAL

Inductor / Magnetics — Inductor_Magnetics_TYPEID_Value_Current_[DCR]_Package_[AECQ]

Type	Prefix	Format detail
PWR Power inductor	Inductor_Magnetics_PWR	Inductor_Magnetics_PWR_L_Isat_DCR_Package (L e.g. 10uH, Isat 3A)
FBD Ferrite bead	Inductor_Magnetics_FBD	Inductor_Magnetics_FBD_Impedance@freq_Current_Package (e.g. Inductor_Magnetics_FBD_600Ω@100MHz_2A_0603)
CMC Common-mode choke	Inductor_Magnetics_CMC	Inductor_Magnetics_CMC_Impedance@freq_Current_Package
RFI RFI choke	Inductor_Magnetics_RFI	Inductor_Magnetics_RFI_L_Current_Package
XFM Transformer	Inductor_Magnetics_XFM	Inductor_Magnetics_XFM_Ratio_Power_Package (ratio e.g. 1:1)
CTX Current transformer	Inductor_Magnetics_CTX	Inductor_Magnetics_CTX_Ratio_Package (e.g. 1000:1)
CPL Coupled inductor	Inductor_Magnetics_CPL	Inductor_Magnetics_CPL_L_Current_Package

Diode — reverse-voltage / current ratings, then package

The prefix is the generic diode type code (the typeid itself) — REC, FRD, SCH, SIC, ZEN, TVS, ESD, SWI, BRG, LED — not a DIO-x form.

Type	Prefix	Format
REC Rectifier	Diode_REC	Diode_REC_Vrrm_Io_Package
FRD Fast-recovery	Diode_FRD	Diode_FRD_Vrrm_Io_trr_Package
SCH Schottky	Diode_SCH	Diode_SCH_Vr_Io_Package
SIC SiC Schottky	Diode_SIC	Diode_SIC_Vr_Io_Package
ZEN Zener	Diode_ZEN	Diode_ZEN_Vz_Power_Package
TVS TVS	Diode_TVS	Diode_TVS_Vbr_Vc_Ip_Package
ESD ESD protection	Diode_ESD	Diode_ESD_Vrwm_Vc_Channels_Package
SWI Switching/small-signal	Diode_SWI	Diode_SWI_Vr_Io_trr_Package
BRG Bridge rectifier	Diode_BRG	Diode_BRG_Vrrm_Io_Package
LED Indicator LED	Diode_LED	Diode_LED_Color_Vf_If_Package (color e.g. RED)

Example (Schottky BAT46WJ, 100 V / 250 mA): Diode_SCH_100V_0.25A_SOD-323F

Transistor — Transistor_TYPEID_[Polarity]_Voltage_Current_[Rds(on)]_Package_[AECQ]

Since the prefix is now Transistor_TYPEID, the polarity/channel can no longer ride in the prefix (the old NMOS/PMOS/BJT_NPN tokens are retired). It is carried as its own token immediately after the prefix: N/P for FETs, NPN/PNP for BJTs and digital transistors. Types with no polarity variant (GaN, IGBT) omit the token entirely.

Type	Prefix	Format
BJT BJT	Transistor_BJT	Transistor_BJT_Polarity_Vceo_Ic_Package (polarity NPN/PNP)
MOS MOSFET (Si)	Transistor_MOS	Transistor_MOS_Channel_Vds_Id_Rdson_Package (channel N/P)
SCM SiC MOSFET	Transistor_SCM	Transistor_SCM_Channel_Vds_Id_Rdson_Package
GAN GaN FET	Transistor_GAN	Transistor_GAN_Vds_Id_Rdson_Package
IGBT IGBT	Transistor_IGBT	Transistor_IGBT_Vces_Ic_Package
JFET JFET	Transistor_JFET	Transistor_JFET_Channel_Vds_Idss_Package
DIG Digital/bias-R transistor	Transistor_DIG	Transistor_DIG_Polarity_Vceo_R1/R2_Package

Example: Transistor_MOS_N_20V_6A_15mΩ_SOT-23 · Transistor_BJT_NPN_50V_0.1A_SOT-416FL

Integrated Circuit (IC) — one line per subtype; package always last (before AECQ)

Type	Prefix	Format
MCU Microcontroller	IC_MCU	IC_MCU_Core_Flash_Package (e.g. IC_MCU_M0+_128Kb_LQFP-48)
LDO LDO regulator	IC_LDO	IC_LDO_Vout_Iout_Package (ADJ if adjustable)
DCD DC-DC IC	IC_DCD	IC_DCD_Topology_Vin_Iout_Package (topology BUCK/BOOST/BUCKBOOST)
PMU PMIC	IC_PMU	IC_PMU_Rails_Package
BMS BMS AFE	IC_BMS	IC_BMS_Cells_Package (e.g. 16S)
DRV Gate/motor driver	IC_DRV	IC_DRV_Type_Voltage_Current_Package (type GATE/MOTOR/HB)
AMP Amplifier/op-amp	IC_AMP	IC_AMP_GBW_Channels_Package
CMP Comparator	IC_CMP	IC_CMP_Channels_Package
VRF Voltage reference	IC_VRF	IC_VRF_Voltage_Tolerance_Package
ADC ADC	IC_ADC	IC_ADC_Bits_Rate_Package
DAC DAC	IC_DAC	IC_DAC_Bits_Channels_Package
ISO Isolator/optocoupler	IC_ISO	IC_ISO_Channels_IsolationV_Package
XCV Transceiver	IC_XCV	IC_XCV_Bus_Speed_Package (bus CAN/RS485; e.g. IC_XCV_CAN_5Mbps_SOIC-8)
AFE Analog front end	IC_AFE	IC_AFE_Function_Package
MEM Memory	IC_MEM	IC_MEM_Type_Size_Interface_Package (e.g. IC_MEM_FLASH_128Mb_SPI_SOIC-8)
LOG Logic gate	IC_LOG	IC_LOG_Function_Package (e.g. AND2, BUF)
SEN Sensor IC	IC_SEN	IC_SEN_Type_Package
IFC Interface/expander	IC_IFC	IC_IFC_Function_Package
CLK Clock/RTC	IC_CLK	IC_CLK_Freq_Package (or RTC_Package)
SVR Supervisor/reset	IC_SVR	IC_SVR_Threshold_Package
MTR Energy metering	IC_MTR	IC_MTR_Phases_Package

Protection Device — Protection_TYPEID_ratings_Package

Type	Prefix	Format
FUS Fuse	Protection_FUS	Protection_FUS_Current_Voltage_Package (speed F/T may precede current)
RSF Resettable/PPTC	Protection_RSF	Protection_RSF_Ihold_Voltage_Package
VAR Varistor/MOV	Protection_VAR	Protection_VAR_Vrms_Energy_Package
GDT Gas-discharge tube	Protection_GDT	Protection_GDT_Vspark_Package
CBK Circuit breaker	Protection_CBK	Protection_CBK_Current_Poles_Package

Power Conversion Module — Power_Conversion_Module_TYPEID_Vin_Vout_Power_Package

Type	Prefix	Notes
DCM DC-DC module	Power_Conversion_Module_DCM	non-isolated PoL
IDC Isolated DC-DC	Power_Conversion_Module_IDC	isolated brick
INV Inverter (DC-AC)	Power_Conversion_Module_INV	Power_Conversion_Module_INV_Power_Voltage_Package
OBC On-board charger	Power_Conversion_Module_OBC	Power_Conversion_Module_OBC_Power_Voltage_Package
CHG Charger module	Power_Conversion_Module_CHG	Power_Conversion_Module_CHG_Power_Voltage_Package
PSU AC-DC SMPS	Power_Conversion_Module_PSU	Power_Conversion_Module_PSU_Power_Vout_Package
RCM Rectifier module	Power_Conversion_Module_RCM	Power_Conversion_Module_RCM_Current_Voltage_Package

Relay / Contactor — Relay_Contactor_TYPEID_CoilVoltage_ContactRating_Package

Type	Prefix	Notes
RLS Signal relay	Relay_Contactor_RLS	contact rating e.g. 2A/30V
RLP Power relay	Relay_Contactor_RLP
SSR Solid-state relay	Relay_Contactor_SSR	Relay_Contactor_SSR_ControlV_LoadRating_Package
RLR Reed relay	Relay_Contactor_RLR
CTC Contactor	Relay_Contactor_CTC	HV/HC contact rating

Switch / Button — Switch_Button_TYPEID_[Positions]_Rating_Package

Type	Prefix	Notes
SWT Tactile	Switch_Button_SWT	rating e.g. 50mA/12V
PBT Push button	Switch_Button_PBT
DSW DIP/slide	Switch_Button_DSW	positions e.g. 4P
RSW Rocker/toggle	Switch_Button_RSW
RSY Rotary	Switch_Button_RSY	positions e.g. 12POS

Connector — Connector_TYPEID_Positions_Pitch_Package

Type	Prefix	Notes
CWB Wire-to-board	Connector_CWB	e.g. Connector_CWB_2x2_P2.0
CBB Board-to-board	Connector_CBB
HDR Header/socket	Connector_HDR	pitch e.g. 2.54mm
FFC FFC/FPC	Connector_FFC
USB USB/data	Connector_USB	add USB type (C, MICRO)
PWC Power/high-current	Connector_PWC	add current rating
TBK Terminal block	Connector_TBK

Antenna / RF — Antenna_RF_TYPEID_Band_Package

Type	Prefix	Notes
ANC Chip antenna	Antenna_RF_ANC	band e.g. 2.4GHz
ANP PCB/trace antenna	Antenna_RF_ANP
ANE External/whip	Antenna_RF_ANE	add connector token
SAW SAW filter	Antenna_RF_SAW	Antenna_RF_SAW_Freq_Package
RFM RF/wireless module	Antenna_RF_RFM	protocol e.g. BLE, WIFI, LTE

Crystal / Oscillator / Timing — Crystal_Oscillator_TYPEID_Freq_[Load]_Package

Type	Prefix	Notes
XTL Crystal	Crystal_Oscillator_XTL	Crystal_Oscillator_XTL_Freq_LoadCap_Package (e.g. Crystal_Oscillator_XTL_48MHz_18pF_SMD2016-4P)
OSC Crystal oscillator	Crystal_Oscillator_OSC	Crystal_Oscillator_OSC_Freq_Package
MMO MEMS oscillator	Crystal_Oscillator_MMO
RSN Ceramic resonator	Crystal_Oscillator_RSN	Crystal_Oscillator_RSN_Freq_Package

Battery / Cell — Battery_Cell_TYPEID_Capacity_Voltage_Format

Type	Prefix	Notes
CLI Li-ion cell	Battery_Cell_CLI	format e.g. 18650; capacity 2600mAh
CLF LiFePO4 cell	Battery_Cell_CLF
CCO Coin/button	Battery_Cell_CCO	add chemistry (CR/LIR) + size (2032)
CNI NiMH	Battery_Cell_CNI
BPK Battery pack	Battery_Cell_BPK	Battery_Cell_BPK_Voltage_Capacity (e.g. 48V_20Ah)
CHL Cell holder	Battery_Cell_CHL	Battery_Cell_CHL_CellType_Package

Audible / Indicator

Type	Prefix	Format
BUZ Magnetic buzzer	Audible_Indicator_BUZ	Audible_Indicator_BUZ_Voltage_Freq_Package
PBZ Piezo buzzer	Audible_Indicator_PBZ	Audible_Indicator_PBZ_Voltage_Freq_Package
SPK Speaker	Audible_Indicator_SPK	Audible_Indicator_SPK_Power_Impedance_Package
IND Indicator lamp	Audible_Indicator_IND	Audible_Indicator_IND_Color_Voltage_Package

Display / HMI — Display_HMI_TYPEID_Resolution/Digits_Size_Interface

Type	Prefix	Notes
DSG 7-segment	Display_HMI_DSG	Display_HMI_DSG_Digits_Color_Package
OLE OLED	Display_HMI_OLE	resolution e.g. 128x64, size 0.96in
LCD LCD	Display_HMI_LCD	char (16x2) or graphic resolution
TFT TFT	Display_HMI_TFT	resolution + size + interface (SPI/RGB)

Sensor (discrete / module) — Sensor_TYPEID_Range_[Interface]_Package

Type	Prefix	Notes
STE Temperature	Sensor_STE	range + interface (I2C/ANALOG)
SCU Current (Hall)	Sensor_SCU	range e.g. ±50A
SVO Voltage/isolated	Sensor_SVO
SHA Hall/position	Sensor_SHA	type (LATCH/LINEAR)
SIM IMU/accel	Sensor_SIM	axes (6AXIS) + interface
SPR Pressure	Sensor_SPR	range + interface

Thermal / Cooling

Type	Prefix	Format
FAN Fan	Thermal_Cooling_FAN	Thermal_Cooling_FAN_Size_Voltage_Airflow (size e.g. 40x40mm)
HSK Heatsink	Thermal_Cooling_HSK	Thermal_Cooling_HSK_Dimensions_ThermalResistance
TPD Thermal pad/TIM	Thermal_Cooling_TPD	Thermal_Cooling_TPD_Conductivity_Thickness

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When a part doesn't fit

The Layer-2 formats are the working house standard, but real datasheets vary. If a part is missing a token the format asks for, leave it out and flag it. If it has a defining rating the format doesn't capture, add it in the sensible position and tell the engineer what you added so the convention can be updated deliberately. Never silently bend a format — an inconsistent Description is worse than one confirmed question. The Layer-1 (SOP) formats are fixed and are not up for reinterpretation.