[minima] Re: Auto-calibration of the Si570 + some refactoring
- From: "Steve VK2SJA" <vk2sja@xxxxxxxxxxx>
- To: minima@xxxxxxxxxxxxx
- Date: Tue, 11 Feb 2014 10:15:35 +1100
> ... default frequency programmed by the factory. In my
> case it was 56.320 but your mileage may vary.
>
> There are two ways to find this frequency:
> - Spec: Look on the marking on your Si570 (mine says CAC000141) and
> lookup some tables online to find which frequency corresponds to your
> marking (I cant find this table, if someone has it, please share!)
I didn't find a simple table. But I have found a Silicon Labs web page
that is linked to a database. You enter the part number and it displays
the chip information including the start-up frequency.
Go to URL:-
http://www.silabs.com/products/clocksoscillators/Pages/Utilityintro.aspx
Use Option 1. Then use default sub-option of "Oscillator".
Enter you Si570 part number starting with 570. For Thomas's chip above you
would enter:-
570CAC000141
Press to "Go" button which looks like a right arrow.
Results returned tell us that it was a custom ordered chip with a start up
frequency of 56.32 MHz. Along with some other important and useful
information:-
Existing Custom Parts 1 result
570CAC000141DG
Product Si570
Startup Frequency 56.32 MHz
I2C Address (Hex Format) 55
Format CMOS
Supply Voltage 3.3 V
OE Polarity OE active high
Stability 61.5 ppm
Frequency Range Exception Value 10 - 160 MHz
Operating Temp Range (°C) -40 to +85
73, Steve.
VK2SJA
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