Dynomotion

Group: DynoMotion Message: 11883 From: holger.strahl Date: 7/12/2015
Subject: Kflop+Kanalog does not boot with load on JP6

Hello, 


I am testing my recently purchased Kanalog with my Kflop. 

Both together have a weird boot behavior:

If there is a load of 150mA on the 5V Power supply of JP6 Flop is not able to initialize Kanalog: After the 2 LEDs of Kflop stopped flashing there is a weak flash on Kanalog and now Kflop starts flashing again. This goes on and on...

Kflop alone starts with the same load. 

Without this load both together boot as expected. 


Can this be a normal behavior? 

Please advice what to do that both boot together with this load.  


Best regards 

Holger Strahl
Group: DynoMotion Message: 11884 From: Tom Kerekes Date: 7/12/2015
Subject: Re: Kflop+Kanalog does not boot with load on JP6
Hi Holger,

What rating is your +5V supply for KFLOP+Kanalog (USB power is not sufficient).

How is it wired?

When Kanalog is first enabled the on-board +/-15V generator causes a significant power surge from the +5V supply.

Regards
TK

Group: DynoMotion Message: 11885 From: holger.strahl Date: 7/12/2015
Subject: Re: Kflop+Kanalog does not boot with load on JP6
Hi Tom, 

For power supply I use an external power supply from PeakTech (6135) connected to JR1 5V pin and Ground. 
The power supply shows the actual current. During the boot process it raises up to 900mA. The voltage stays stable. 

Regards
Holger
Group: DynoMotion Message: 11886 From: Tom Kerekes Date: 7/12/2015
Subject: Re: Kflop+Kanalog does not boot with load on JP6
Hi Holger,

Does that have adjustable current limit up to 3A?  Is it set at 3A?

The Power Supply meter may not show the peak current of the appropriate time scale.

What gauge wire are you using and how long are the wires to the power supply?

Could you try another switching 2A or greater +5V supply with short wiring?

What Rev of KFLOP board do you have?  Rev 1.2 and earlier had some susceptibility to noise coupling into the KFLOP Reset Input when longer ribbon cables were connected to the connectors such as JP6.  But I suppose noise there would be unlikely to occur when Kanalog is enabled.  What are you powering and what is connected to KFLOP JP6?

Regards
TK

Group: DynoMotion Message: 11897 From: Holger Strahl Date: 7/14/2015
Subject: Re: Kflop+Kanalog does not boot with load on JP6
Hi Tom,

I powered an encoder with the pins from JP6.
I've changed the current limit from 2A to 3A with no impact.
But, based on your information I found two solutions to solve the issue: 
1. Using much shorter wiring for the power supply of Kflop
2. Using the power pin forom JP4. (That could indicate an interference with Kflop reset on JP6...)

Holger



On Sunday, July 12, 2015 9:10 PM, "Tom Kerekes tk@... [DynoMotion]" <DynoMotion@yahoogroups.com> wrote:


 
Hi Holger,

Does that have adjustable current limit up to 3A?  Is it set at 3A?

The Power Supply meter may not show the peak current of the appropriate time scale.

What gauge wire are you using and how long are the wires to the power supply?

Could you try another switching 2A or greater +5V supply with short wiring?

What Rev of KFLOP board do you have?  Rev 1.2 and earlier had some susceptibility to noise coupling into the KFLOP Reset Input when longer ribbon cables were connected to the connectors such as JP6.  But I suppose noise there would be unlikely to occur when Kanalog is enabled.  What are you powering and what is connected to KFLOP JP6?

Regards
TK