How to convert 10 mhz crystal oscillator to 3.57 mhz ?

[ajaykumar988]

1/12 oscillator

How to convert 10 mhz crystal oscillator to 3.57 mhz ?help me please

 

[echo47]

quartz crystal oscillator for 3.57mhz

You could use a PLL frequency synthesizer. Search around for design suggestions.

If you are referring to the NTSC color subcarrier frequency, the exact conversion ratio is 10 MHz * 63 / 176.

Or how about simply buying a crystal (or oscillator) at the desired frequency?

 

[saim2k]

3.57 mhz chips

Normally a divider converts HF to LF but I dont see any possible divider in your case, like 10/=3.33

 

[Shurik]

3.57 crystal

may be so?

module div (C10M, R);
input C10M;
input R;

reg [4:0] DIV_10;
reg [1:0] GEN_3_75;

wire CORRECT = DIV_10[4] & DIV_10[3] & ~DIV_10[2] & DIV_10[1] & DIV_10[0];
wire C3_57 = GEN_3_75[1] | CORRECT ;

always @(posedge C10M or posedge R or posedge CORRECT)
if (R)
GEN_3_75 = 2'h0;
else
if (CORRECT)
GEN_3_75 = 2'h0;
else
if (GEN_3_75 == 2'h2)
GEN_3_75 = 2'h0;
else
GEN_3_75 = GEN_3_75 + 1;

always @(negedge C10M or posedge R)
if (R)
DIV_10 = 5'h0;
else
if (DIV_10 == 5'd27)
DIV_10 = 5'h0;
else
DIV_10 = DIV_10 + 1;

endmodule

 

[echo47]

convert:162 mhz to mhz

In case anyone is wondering, Shurik's Verilog code generates 357 pulses on signal C3_57 for every 1000 input clocks. The pulse spacing is non-uniform, of course.

 

[Shurik]

@10mhz crystal oscillator

To echo47

Is it not correctly ?

 

[echo47]

crystal oscillator 3.57mhz

I briefly described your code to help readers who don't know Verilog. I don't know if it will help ajaykumar988. He may require uniformly spaced pulses. Also, his "3.57" value seems suspicious to me - he may have rounded-off the common frequency "3.57954545...". But we don't know!

 

[bmwcoupe]

crastal oscillator 3.57mhz

you need FREQUENCY DIVIDER (like flip flop)
or MIXER , it's not a problem there are alot of chips like that.

and for exact frequency after being divided , you should design
AFC circuit.

Added after 13 seconds:

you need FREQUENCY DIVIDER (like flip flop)
or MIXER , it's not a problem there are alot of chips like that.

and for exact frequency after being divided , you should design
AFC circuit.

 

[Shurik]

2 mhz crystal

To echo47

I briefly described your code to help readers who don't know Verilog. I don't know if it will help ajaykumar988. He may require uniformly spaced pulses. Also, his "3.57" value seems suspicious to me - he may have rounded-off the common frequency "3.57954545...". But we don't know!

I have only asked !!!