Defining Parameters using the CAD Model Style Guide

The parameters section of the guide concentrates on the foundational attributes essential for precisely characterizing electronic components within CAD libraries. These parameters are categorized into three primary groups: Generic Parameters, which apply to all components; Device-Specific Parameters, which vary according to the type and function of the component; and Suggested Parameters, which provide supplementary, non-crucial details that enhance component understanding and selection.

Generic Parameters

This section covers the generic parameters that should be included for each component.

Manufacturer Part Number: This is the full orderable manufacturer component number that can be found on a distributor website.
Datasheet Revision: This is the revision number, letter or date of a component’s datasheet.
Manufacturer: This is the full name of the manufacturer that currently makes the component. Use the full manufacturer name, not an abbreviation.
IPC Standard: If a standard or multiple standards were followed to create a footprint, the standard name(s) should be added to the value of the parameter.
Lead Free: This indicates whether the component is lead-free (Yes, No, Unknown).
Description: This should be an aggregation of a component's main category (Passive, Connector, Discrete, etc.), subcategory (Capacitors, Card Edge, Diodes), and the vital parameters of the components. Some suggestions are:
- The sequence of the parameters in the description should be consistent across the component library.
- Only include the main category (Passive, Integrated Circuit, Connector, etc.) in the description for Integrated Circuit components and connectors, for all other components, only include the first subcategory from the main category (Resistor, Embedded Processor, Header, etc.) and the final category (Network, FPGA, Right-Angle, etc.).
  
  Examples:
  
  RES, Thick Film, 2.7 kOhm, ±1%, 2 W, Automotive, 2010
  IC, Microcontroller, 32-Bit, 120 MHz, 512 kB (512 k x 8), 64-LFQFP (10x10)
  CONN, Header, Right-Angle, 04 Pos, 1.25 mm Pitch, Gold, SMD

Package Code: The descriptive designation for semiconductor-device packages follows JEDEC Standard No. 30E. The system is based on a mandatory field that includes a three-letter basic package designator (comprising a two-letter package outline style code). The designator indicates the package outline style and terminal position or form, preceded by a field that indicates the package-body material. Per JEDEC Standard No. 30E, this mandatory package designator can be extended with user-selected fields to provide additional package information, such as specific package features, package differentiators, terminal count, and supplemental information. These fields are separated from the descriptive designator by a slash (/).

The list below is not exhaustive. Please refer to the standard list of package-outline-style codes in the tables of the various Annex sections of the JEDEC Standard No. 30E for comprehensive details.

Table 1. Common Packages, Designators and Descriptions
Basic Pkg. Designator	Common Pkg. Name	Description
BGA	Ball Grid Array	A grid-array package with balls or bumps on the bottom surface.
CGA	Column Grid Array	A grid-array package with columns on the bottom surface.
DIM	Dual In-line Module	An in-line module with terminal pad surfaces on both surfaces of a printed circuit board substrate.
DIP	Dual In-line Package	An in-line package with leads in parallel rows on opposite sides of the package body for through-hole insertion.
DSO	Small-outline Package	A small outline package with gull-wing-shaped leads on two opposite sides.
DSB	Die-size BGA	A BGA that is the size of the die it contains and whose size will change with changes in die size.
LGA	Land Grid Array	A grid-array package with terminal pads on the bottom surface.
PGA	Pin Grid Array	A grid-array package with pins protruding from the bottom surface.
QFF	---	A flat-type package with flat, unformed leads extending from four sides.
QFJ	---	A flat-type package with J-shaped leads on four sides.
QFN	---	A flat-type package with terminal pads (no leads) along the four edges of the bottom surface.
QFP	Quad Flatpack	A flat-type package with gull-wing-shaped leads on four sides.
SIM	Single In-line Module	An in-line module with terminal pad surfaces on only one surface of a printed circuit board substrate.
SIP	Single In-line Package	An in-line package with leads on only one side.
SKT	Socket	An array of terminals embedded in a nonconductive shell typically used as an electromechanical interface.
SOF	---	A small-outline package with unformed (flat) leads on two opposite sides.
SOJ	---	A small-outline package with J-shaped leads on two opposite sides.
SON	---	A small-outline package with terminal pads along two opposite edges of the bottom surface.
SVP	---	A vertical surface-mount package with supporting posts.
UCI	Tape Carrier Package	An uncased chip with leads extending outward in four directions on an insulating film.
WLB	Wafer-level BGA	A BGA that is processed on an entire wafer before singulation rather than on an individual die, and whose size will change with changes in die size.
ZIP	Zigzag in-line package	An in-line package with zigzag leads on only one side for through-hole insertion into a printed circuit board.

A single-letter prefix is used to identify the predominant package-body material. The package-body-material prefix is the first field of the mandatory descriptive designator and must be included. The prefixes for the predominant package-body material per JEDEC Standard No. 30E are below. For more details, refer to 3.2.2 Package-body material, table 2, JEDEC Standard No. 30E.

Table 2. Prefixes for predominant package-body material
Code	Material
C	Ceramic, metal-sealed, co-fired
G	Ceramic, glass-sealed
M	Metal
P	Plastic (molding compound, glob-top, and printed circuit board-like substrates)
S	Silicon
T	Tape (usually polyimide), where tape is an integral part of the package

Example JEDEC JESD30 document descriptive designators:

TBGA-196/MO-149AA-1X
CPGA-256/MO-067BH
PQFP

RoHS Compliant: This is the Restriction of Hazardous Substances directive (Yes, No, Unknown). The main source of this information should be in the component datasheet or the manufacturer’s product page.
Max Operating Temperature: This is the maximum operating temperature at which a component can function properly (85 ºC, 125 ºC, etc.). The main source of this information is in the datasheet or the manufacturer’s product page.
Min Operating Temperature: This is the minimum operating temperature at which a component can function properly (-40 ºC, -55 ºC, etc.). The main source of this information is in the datasheet or the manufacturer’s product page.
Manufacturer’s Product Catalog: This is the URL to the manufacturer’s product catalog page, if available.
Manufacturer’s Product Page: This is the URL to the manufacturer’s product page, if available.
Manufacturer’s Package Drawing: This is the URL to the manufacturer’s package drawing, if available.
Manufacturer’s Recommended Land Pattern: This is the URL to the manufacturer’s recommended land pattern, if available.

Device-specific Parameters

This section covers the device-specific parameters that should be included for each component type based on main category and subcategories. The list below is not exhaustive.

Table 3. Device-specific Parameters for Integrated Circuits and Discrete Semiconductors
Main Category	Subcategory	Subcategory	Device-specific Parameter Name
Integrated Circuits (ICs)	Power Management ICs	Base	Max Supply Voltage Min Supply Voltage Max Supply Current Max Power Dissipation Number of Outputs Output Voltage Output Current
		Battery Management	Number of Cells Chemistry/Technology Interface
		Gate Drivers	Number of Drivers Propagation Delay Turn-On Delay Time Turn-Off Delay Time Rise Time Fall Time Logic Voltage - VIL max Logic Voltage - VIH min Current - Peak Output Source Current - Peak Output Sink Switching frequency Configuration
		Hot Swap Controllers	Number of Channels On-State Resistance Turn-On Delay Time Turn-Off Delay Time
		LED Drivers	Switching Frequency Number of Outputs Switching Topology Dimming Interface
		Motor Drivers	Switching Frequency Number of Outputs Motor Type Configuration Interface
		Voltage References	Accuracy Temperature Coefficient Reference Type Output Type
		Voltage Regulators - Linear	Accuracy Percentage Dropout Voltage Output Type
		Voltage Regulators - Switching	Switching Frequency Switching Topology Max Duty Cycle Negative Voltage Available Output Type
		Voltage Supervisors	Reset Type Threshold Voltage Watchdog Timer Number of Rails Monitored Reset Timeout
	Embedded Processors and Controllers	Base	Frequency Max Supply Voltage Min Supply Voltage Nominal Supply Current Program Memory Size Program Memory Type Number of I/Os
		CPLDs - Complex Programming Logic Devices	Number of Gates Number of Logic Blocks (LABs) Number of Logic Elements/Cells Number of Macrocells Propagation Delay Speed Grade
		FPGAs - Field Programmable Gate Arrays	Number of Gates Number of Logic Blocks (LABs) Number of Logic Elements/Cells Speed Grade Block RAM size Number of Registers
		DSPs - Digital Signal Processors \| Microcontrollers \| Microprocessors	Core Architecture Number of Cores Memory Map Size Data Bus Width Interface Number of A/D Converters Number of ADC Channels Number of Ethernet Channels Number of I²C Channels Number of PWM Channels Number of SPI Channels Number of Timers/Counters Number of UART Channels Number of USB Channels RAM Size
		Single Board Computers (SBCs)	Core Architecture Interface RAM Size
	Data Converter ICs	Base	Interface Max Supply Voltage Min Supply Voltage Max Supply Current
		Analog to Digital Converters (ADCs) \| Digital to Analog Converters (DACs)	Number of Channels Number of Converters Resolution Sampling Rate
		Analog to Digital Converters (ADCs)	Number of Channels Number of Converters Resolution Sampling Rate Differential Input Reference Type Max Analog Supply Voltage Min Analog Supply Voltage Max Analog Supply Current
		Digital to Analog Converters (DACs)	Number of Channels Number of Converters Resolution Setting Time Differential Output Reference Type Max Analog Supply Voltage Min Analog Supply Voltage Max Analog Supply Current
		Digital Potentiometers	Tolerance Nominal Resistance Temperature Coefficient Number of Taps Number of Circuits Memory Type Potentiometer Memory Type Taper
		Touch Screen Controllers	Number of Channels Resolution Sampling Rate Touchscreen Style Touch Screen Wires Number
		Analog Front End (AFE)	Number of Channels Resolution Max AC Supply Voltage Min AC Supply Voltage Nominal AC Supply Voltage Max Analog Supply Voltage Min Analog Supply Voltage Max Analog Supply Current
	Linear ICs	Base	Max Supply Voltage Min Supply Voltage Max Dual Supply Voltage Min Dual Supply Voltage Max Supply Current Number of Channels Max Voltage Gain Input Offset Voltage (Vos) Input Bias Current Short Circuit Current Bandwidth -3 dB Gain Bandwidth Product Settling Time
	Linear ICs	Amplifiers - Audio	Max Power @ Load Power Amplifier Class
	Interface ICs	Base	Max Supply Voltage Min Supply Voltage Max Supply Current Interface
		CODECs	Resolution Sampling Rate Number of A/D Converters Number of D/A Converters Number of Analog Inputs Number of Analog Outputs
		Ethernet Interface ICs	Data Rate Number of Channels Simplex/Duplex Standards Physical Medium Function
		RS-232 / RS-422 / RS-485 Interface ICs	Data Rate Simplex/Duplex Number of Receivers Number of Transmitters
		UART Interface ICs	Data Rate Number of Channels Memory Size
		USB Interface ICs	Data Rate USB Standard Number of Ports
		Voice Record and Playback	Duration
		Telecom, Tone Decoder, DTMF, DAA, SLIC, LIU, PLMD	Number of Circuits Max Supply Current
		Signal Termination Interface	Termination Type Number of Circuits
		Signal Buffers, Repeaters, Splitters	Input Capacitance Delay Time Data Rate Type
		Serializers, Deserializers	Data Rate Number of Inputs Number of Outputs Type Input Electrical Type Output Electrical Type
		Sensor and Detector Interfaces	Sensor Type Input Type Output Type
		I/O Expanders	Frequency Number of I/Os
		Active Filters	Cut-off Frequency Filter Type Number of Circuits Filter order
		Direct Digital Synthesis (DDS)	Resolution Maximum Clock Frequency
		Controllers	Function
		Analog Switches, Multiplexers, Demultiplexers	Throw Configuration Number of Circuits Mux:Demux Ratio (M:D) On-State Resistance -3dB Bandwidth
Discrete Semiconductor	Diodes	Base	Forward Current Reverse Voltage
		Rectifier Diodes \| Schottky Diodes	Max Surge (Non-Repetitive) Forward Current Peak Reverse Current Max Repetitive Reverse Voltage Capacitance
		Zener Diodes	Power Dissipation Max Zener Voltage Nom Zener Voltage Min Zener Voltage Zener Impedance Max Reverse Leakage Current
	Thyristors	Base	Forward Voltage Hold Current
		DIACs, SIDACs	Max Breakover Voltage Min Breakover Voltage Breakover Current Max On State Current RMS (It RMS)
		SCRs	Max Gate Trigger Voltage (Vgt) Max Gate Trigger Current (Igt) Max On State Voltage (Vtm) Max On State Current (It AV) Max On State Current RMS (It RMS) Max Off State Current Max Off State Voltage
		TRIACs	Max Gate Trigger Voltage (Vgt) Max Gate Trigger Current (Igt) Max On State Current RMS (It RMS) Max Off State Voltage
	Transistors	Base	Total Power Dissipation Max Thermal Resistance Junction to Ambient (Steady - State)
		BJTs	Number of Elements Number of NPN Number of PNP Max Collector Current Collector Emitter Voltage (VCEO) Collector Emitter Saturation Voltage Collector Emitter Breakdown Voltage Collector Base Voltage (VCBO) Emitter Base Voltage (VEBO) Gain Bandwidth Product Unity Gain Frequency fT DC Current Gain hFE Min DC Current Gain hFE Max DC Current Gain hFE Test Ic DC Current Gain hFE Test Vce Small Signal Current Gain hFE Min Small Signal Current Gain hFE Max Small Signal Current Gain hFE Test Ic Small Signal Current Gain hFE Test Vce Delay Time td Rise Time tr Storage Time ts Fall Time tf
		IGBTs	Collector Emitter Voltage (VCEO) Collector Emitter Breakdown Voltage Collector Emitter Saturation Voltage Turn-Off Delay Time Turn-On Delay Time Collector Current
		JFETs	Number of Channels Number of N Channels Number of P Channels Gate to Source Voltage Drain To Source Voltage Breakdown Voltage Continuous Drain Current (ID) Drain To Source Resistance
		MOSFETs	Technology FET transistor type Number of Channels Number of N Channels Number of P Channels Gate to Source Voltage Drain To Source Voltage Continuous Drain Current (ID) Drain To Source Resistance Drain To Source Breakdown Voltage Pulsed Drain Current @ 25 °C Max Threshold Vgs Min Threshold Vgs Transconductance Turn-Off Delay Time Turn-On Delay Time Gate Charge @ Vgs Input Capacitance @ Vds Max Diode Forward Voltage Typical Diode Forward Voltage Diode Reverse Recovery Charge Diode Reverse Recovery Time

Suggested Parameters

Base Part Number: This is an identifier used to categorize a specific type or family of components (LM7805, STM32, ERJH).
Manufacturer’s Website: This is the URL to the component manufacturer’s website.