PCB Libraries Forum : Schematic Symbols

Schematic Symbols : Ferrite Bead symbol and reference designator

Thu, 27 Jun 2024 09:42:12 +0000

Author: Tom H
Subject: Ferrite Bead symbol and reference designator
Posted: 27 Jun 2024 at 9:42am

Class Designation Letters for Reference Designations

A SeparableAssembly

AR Amplifier

AT Attenuator;Isolator

B Blower,Motor

BT Battery

C Capacitor

CB CircuitBreaker

CP ConnectorAdapter, Coupling

CN Capacitor Network

CR BreakdownDiode

D Diode

DC DirectionalCoupler

DL DelayLine

DS Display,Lamp

E Terminal

F Fuse

FD* Fiducial

FL Filter

G Generator,Oscillator

GN GeneralNetwork

H Hardware

HY Circulator

J Connector,Jack, Female

K Contactor,Relay

L Coil,Inductor, Bead, Ferrite Bead

LS Loudspeaker, Buzzer

M Meter

MG Motor-Generator

MH* Mounting Hole

MK Microphone

Q Transistor

MP Mechanical Part

P Connector, Plug, Male

PS Power Supply

R Resistor

RN Resistor Network

RT Thermistor

RV Varistor, Variable Resistor

S Switch

TZ Transzorb

T Transformer

TB Terminal Board, Terminal Strip

TC Thermocouple

TP^**Test Point, In-circuit Test Points

U Inseparable Assembly, IC Pkg

VR Voltage Regulator

W Wire, Cable, Cable Assembly

X Fuse holder, Lamp holder, Socket

Y Crystal, Oscillator

Z Miscellaneous

*Theseclass letters would not appear in a parts list as they are part of a PCB andnot an active electronic component.

^**Not a class letter, butcommonly used to designate test points for maintenance purposes.

Note:The above list is not exhaustive. See the standard list of class designationletters in ANSI Y32.2/IEEE Std. 315, Section 22 and the Index.

Schematic Symbols : Standard Reference Designators

Thu, 27 Jun 2024 09:20:19 +0000

Author: Tom H
Subject: Standard Reference Designators
Posted: 27 Jun 2024 at 9:20am

Here is a list of the electronics industry Standard Reference Designators.

uploads/3/Reference_Designators_2024-06-27_09-19-42.zip

Schematic Symbols : Ferrite Bead symbol and reference designator

Tue, 28 Aug 2018 02:29:25 +0000

Author: LarryJoy
Subject: Ferrite Bead symbol and reference designator
Posted: 28 Aug 2018 at 2:29am

The IEC 60617 graphic symbol for a Ferrite Bead is shown in IEEE 315A, Clause 6.2.11 as follows:

In addition the class letter to use in a ref des is E. See IEEE 315, Clause 22.4.

Schematic Symbols : Ferrite Bead symbol and reference designator

Thu, 21 Dec 2017 02:26:12 +0000

Author: Nick B
Subject: Ferrite Bead symbol and reference designator
Posted: 21 Dec 2017 at 2:26am

I don't know where the temporary link came from, but I modified Tom's post with the proper link.

Please try again...

Schematic Symbols : Ferrite Bead symbol and reference designator

Thu, 21 Dec 2017 00:28:57 +0000

Author: tgrodnicki
Subject: Ferrite Bead symbol and reference designator
Posted: 21 Dec 2017 at 12:28am

Tom H wrote:

Here is a list of common ref des for the past 30 years -

http://www.pcblibraries.com/downloads/temp/Reference_Designators_7537645.pdf ;

"Error 404: Page was Moved!"

In document from 2004 created by PCB Libraries and titled Standard Reference Designators "FB" stands for Ferrite Bead.

I followed standard from this publication.

In document from 2009 created by PCB Matrix and tltled IPC-7351B Naming Convention for Standard SMT Land Patterns in section PCB Matrix Naming Convention for Non-Standard SMT Land Patterns land pattern name for Ferrite Beads is FB_Mfr.'s Part Number.

Current version of lattter document does not have section for non-standard patterns.

Schematic Symbols : Ferrite Bead symbol and reference designator

Wed, 20 Dec 2017 08:45:28 +0000

Author: Tom H
Subject: Ferrite Bead symbol and reference designator
Posted: 20 Dec 2017 at 8:45am

Here is a list of common ref des for the past 30 years -

https://www.pcblibraries.com/forum/common-pcb-reference-designators_topic728.html

They have the same electrical function:

"L" covers Inductors, Beads, Ferrite Beads,
Chokes, Common Mode Chokes and all parts related to the function of an electric
or electronic circuit that possesses inductance used in order to filter common
mode electromagnetic interference (EMI) currents without de-rating under high
currents and without causing signal degradation. Or, the geometry and
electromagnetic properties of coiled wire over the ferrite bead result in an
impedance for high-frequency signals, attenuating high frequency EMI/RFI
electronic noise.

I guess you can use FB for Ferrite Bead. Sounds good to me.

Schematic Symbols : Ferrite Bead symbol and reference designator

Wed, 20 Dec 2017 08:29:32 +0000

Author: bnoel
Subject: Ferrite Bead symbol and reference designator
Posted: 20 Dec 2017 at 8:29am

Hello,

I am seeing some conflicting information online regarding Ferrite Beads. I see some documentation that shows the schematic symbol for a Ferrite Bead as an Inductor with a reference designator of L and other documentation that shows the symbol as in the inserted image with the reference designator of FB.

What is the definitive symbol and ref des?

Schematic Symbols : Alignment pins/Mounting holes

Sun, 17 Sep 2017 02:03:56 +0000

Author: Matthew Lamkin
Subject: Alignment pins/Mounting holes
Posted: 17 Sep 2017 at 2:03am

I would add any hole that has a connection to it into the schematic, as a mapped pin within the library part. This would usually be a separate symbol if there are many of these, so that they can be moved to a corner of the schematic rather than clog up the main drawing area.

You can usually do this like a multi gate device is done in a library part.
There is no need to add alignment pins into the schematic, if it's not electrically connected - it does not "need" to be shown, unless there are overriding reasons for it being shown.

They have the same reference name as the main symbol, otherwise it confuses the reader - so do not use anything else. It is after all the same part.

I did this so that when checking the PCB for faults etc. the person doing this is fully informed of what is connected and what is not.

Otherwise they have to guess and assume and we know what trouble this causes :)

Schematic Symbols : Alignment pins/Mounting holes

Thu, 07 Sep 2017 17:31:35 +0000

Author: Tom H
Subject: Alignment pins/Mounting holes
Posted: 07 Sep 2017 at 5:31pm

There are no global standards on connector symbols, footprints or 3D models..

You should create your own guidelines and adhere to them.

Schematic Symbols : Alignment pins/Mounting holes

Mon, 10 Apr 2017 12:13:43 +0000

Author: dlveazie
Subject: Alignment pins/Mounting holes
Posted: 10 Apr 2017 at 12:13pm

I'm curious if there are any guidelines for symbols and footprints for parts (typically connectors) with alignment and/or mounting pins.

Firstly the symbol. Advised to show all? Only copper features? None? Seems wrong to not use any because more than likely they'll go to GND.

For the footprint, abbreviations (that obviously match symbol if shown) for these types of pins. AP? MH? WT? SHLD?

Obviously there is no "one way" but if there are any suggestions, I'd like to hear them. I'm new to the librarian role and appreciate all the experienced opinions before me.

MH for mounting hole just feels like a screw hole. I like AP# for non-copper alignment pins and WT# for weld tabs but that's only because that's what Samtec calls them.