# Make before break (MBB) analogue switch, almost non existent

#### f_mohsen

Joined Apr 7, 2016
15
I require a make before break analogue switch for a project I am working on. The problem as I have been finding out is that the majority of the analogue switches are Break before make (BBM). For example Analog produces the ADG619 and ADG620 switches. The ADG619 (BBM version) can be easily bought from places like Farnell, but the MBB version ADG620 is no where to be found. The switch I need is a SPDT which can handle both positive and negative signals, as well as being MBB. Has anyone came across this problem? any component suggestions?

#### GopherT

Joined Nov 23, 2012
8,012
I require a make before break analogue switch for a project I am working on. The problem as I have been finding out is that the majority of the analogue switches are Break before make (BBM). For example Analog produces the ADG619 and ADG620 switches. The ADG619 (BBM version) can be easily bought from places like Farnell, but the MBB version ADG620 is no where to be found. The switch I need is a SPDT which can handle both positive and negative signals, as well as being MBB. Has anyone came across this problem? any component suggestions?
Try using two SPST switches instead and control the make/break sequence and overlap time yourself (with timer circuits, or microcontroller, etc)

#### f_mohsen

Joined Apr 7, 2016
15
Try using two SPST switches instead and control the make/break sequence and overlap time yourself (with timer circuits, or microcontroller, etc)
Thanks for your quick response, it sounds like a good solution which I might end up having to do if I can't find the right hardware. But it seems very strange that this switch type is not readily available (I understand that it is less popular for many reasons, least of them shorting the inputs together).

#### f_mohsen

Joined Apr 7, 2016
15
Thank, but I am looking for semiconductor switches, not mechanical ones. I do apologise for my misleading description.

#### KeepItSimpleStupid

Joined Mar 4, 2014
5,088

$100 min. /line item https://www.rocelec.com/ Rochester, I believe, is allowed to make products that are obsoleted by the manufacturer buts still has a demand and they are sanctioned by the manufacturer. You can also check www.littlediode.com http://www.littlediode.com/components/search.php?mode=search&simple_search=Y&posted_data[by_title]=Y&posted_data[by_shortdescr]=Y&posted_data[by_fulldescr]=Y&posted_data[by_sku]=Y&posted_data[including]=all&substring=ADG620BRM&search_redirect=Y for They are a really nice company to deal with and usually respond promptly. If this is for audio/video you might find better solutions. Last edited: Thread Starter #### f_mohsen Joined Apr 7, 2016 15 ADG620$100 min. /line item

https://www.rocelec.com/

Rochester, I believe, is allowed to make products that are obsoleted by the manufacturer buts still has a demand and they are sanctioned by the manufacturer.

You can also check www.littlediode.com

They are a really nice company to deal with and usually respond promptly.

If this is for audio/video you might find better solutions.
This is very interesting, I did not know about that website, but kinda expensive (gotta look at it in more details). What better solution do you have in mind for Audio?

#### dannyf

Joined Sep 13, 2015
2,197
It is possible to construct such a switch?

#### Marcus2012

Joined Feb 22, 2015
425
Hey
There is the 4016 and 4066 of the 4000 series that are bilateral switches but I'm not sure if they are MBB.

Not sure if this fits the bill or is the right package but is this the type of switch you're after?

TS5A3154 0.9-Ω SPDT ANALOG SWITCH

MBB time of 12ns and only one channel though

#### crutschow

Joined Mar 14, 2008
29,802
Why do you need MBB?
What is the application?

#### f_mohsen

Joined Apr 7, 2016
15
It is possible to construct such a switch?

Try using two SPST switches instead and control the make/break sequence and overlap time yourself (with timer circuits, or microcontroller, etc)

#### f_mohsen

Joined Apr 7, 2016
15
Hey
There is the 4016 and 4066 of the 4000 series that are bilateral switches but I'm not sure if they are MBB.

Not sure if this fits the bill or is the right package but is this the type of switch you're after?

TS5A3154 0.9-Ω SPDT ANALOG SWITCH

MBB time of 12ns and only one channel though
TS5A31454 would be perfect but the problem is that it only operates with positive supply, I need to pass both positive and negative signals.

#### f_mohsen

Joined Apr 7, 2016
15
Why do you need MBB?
What is the application?
I am using it in a way that it is not suppose to be used, at the output I have a capacitor. The sudden change in the capacitance of the switch causes a big charge transfer and high voltages for the next stage, thus causing it to rail for a short period of time. I am hoping MBB would at least reduce the degree of this sudden change in capacitance.

#### GopherT

Joined Nov 23, 2012
8,012
I am using it in a way that it is not suppose to be used, at the output I have a capacitor. The sudden change in the capacitance of the switch causes a big charge transfer and high voltages for the next stage, thus causing it to rail for a short period of time. I am hoping MBB would at least reduce the degree of this sudden change in capacitance.
Or you could limit your switching to only when the signal is at the DC bias voltage so the charge on capacitors is always at the bias voltage.

#### f_mohsen

Joined Apr 7, 2016
15
Or you could limit your switching to only when the signal is at the DC bias voltage so the charge on capacitors is always at the bias voltage.
Hhmm, maybe, but I need to sample the signal (and for that switch it) at specific time intervals, so I gotta play around with this idea, thanks

#### GopherT

Joined Nov 23, 2012
8,012
Hhmm, maybe, but I need to sample the signal (and for that switch it) at specific time intervals, so I gotta play around with this idea, thanks
An ADC on a microcontroller should be able to handle your concerns at audio frequencies.

#### crutschow

Joined Mar 14, 2008
29,802
I am using it in a way that it is not suppose to be used, at the output I have a capacitor. The sudden change in the capacitance of the switch causes a big charge transfer and high voltages for the next stage, thus causing it to rail for a short period of time. I am hoping MBB would at least reduce the degree of this sudden change in capacitance.
I don't quite understand.
Could you post a diagram of what you are doing?
There may be another way around your problem.

#### f_mohsen

Joined Apr 7, 2016
15
I don't quite understand.
Could you post a diagram of what you are doing?
There may be another way around your problem.
Please find attached, sorry if it is a bit rough, I do know that perhaps it is not the right way to use these switches.

#### f_mohsen

Joined Apr 7, 2016
15

\$100 min. /line item

https://www.rocelec.com/

Rochester, I believe, is allowed to make products that are obsoleted by the manufacturer buts still has a demand and they are sanctioned by the manufacturer.

You can also check www.littlediode.com