Using the DAC with FSM0/FSM1

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Matthew H.
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Last seen: 1 year 7 months ago
Joined: 2020-09-28 19:36
Using the DAC with FSM0/FSM1

Hi all, I'm trying to figure out how to connect either DAC0 or DAC1 to a FSM block similar to
this example: 

https://www.dialog-semiconductor.com/greenpak-cookbook/pwm-generator-usi...

So I can make an 8 bit up/down counter that can be both incremented and decremented and the
value sent to the DAC. Though the datasheet for the SLG46620 seems to indicate that the FSM
outputs can be routed to the DACs this doesn't appear to be possible in practice within the designer
software, I'm only seeing options for sources on DAC0 and DAC1 as "Register" and "From DCMP1"
for that device.

So it's not so easy to immediately determine which devices are actually capable of the type of routing as shown in the 
instructional guide as the datasheet seems to not agree with the software. Could anyone advise which
products can acutally be routed that way? Thanks

Device: 
Device Number: 
SLG46620
olehs
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Last seen: 1 year 7 months ago
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Joined: 2018-02-07 11:40
Hi Matthew H., 

Hi Matthew H., 

Thank you for your question! 

If you didn't see there is the design file just below the description, so you can use it as a reference, but this design was made by using SLG46140. Soon we will update the Cookbook chapters with a detailed description of the DAC control. 

Regarding the DAC control in SLG46620V. It is similar to SLG46140. So, please use the following steps to create the DAC control:

1. Configure Vref0 Source selection to DAC0 out;

2. Configure DCMP1 In- selector to FSM0->Q[7:0] (note: Don't need to power on the DCMP1, just change the setting as is on the picture in the attachment);

3. Configure DAC0 Input selection to From DCMP1's input and Power On the DAC0. After that 14-bit CNT2 automatically was connected to the DAC0;

4. Configure 14-bit CNT2 to Counter/FSM Mode;

5. Change RC OSC power to Force power on.

After you made all these steps you will be able to control DAC via FSM0 (using UP/DOWN, Keep, Reset signals) and the analog voltage will be applied to PIN19. In case if I missed something or you have some troubles with block configuration I've also attached the design. 

Please let me know if you have some other questions regarding the DAC or GPAK itself

Best regards, 

Oleh Sapiha  

Matthew H.
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Last seen: 1 year 7 months ago
Joined: 2020-09-28 19:36
Thank you, that does it!

Thank you, that does it!

olehs
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Last seen: 1 year 7 months ago
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Joined: 2018-02-07 11:40
Hi Matthew H.

Hi Matthew H.

 

My pleasure

 

Best regards,

Oleh Sapiha