Clocks Forum Discussions

Programmable Oscillator CY29430

• If I program this oscillator to have LVDS output waveform logic at supply voltage Vdd = 1.8V, it's evident through a few of your application notes and testing that this combination does not exhibit standard output waveform voltage values for LVDS logic (voltage is too low).
• Cypress App. note referenced: http://www.cypress.com/file/294351/download
• In the above app note, it says the LVDS 1.8V combination requires the output common mode voltage (VOCM) to be supplied externally (along with implementing  AC coupling between the clock device and the receiver circuit) in order to exhibit standard output waveform voltage values -

Question:

• Is there a certain value Cypress suggests to apply for the external output common mode voltage?

Hi

Please provide Difference between two Different ordering Part Numbers

Is it possible to reprogram factory programmed (pre-programmed) CY22393ZXC-xxx / CY22394ZXC-xxx / CY22395ZXC-xxx devices using the CY3672 with CY3672ADP003A adapter to change the default output frequencies ?

This question was posted over 10 years ago already but never answered.

There was a similar question around the same time for the CY22392, this one was answered and due to the lack of the I2C bus pins on that device, apparently only the factory would be able to reprogram the CY22392.

I'm hoping that because the CY22393/4/5 does have the I2C pins, that the CY3672 programmer can be used to reprogram factory pre-programmed parts.

Does the CY2304NZ output tristate when OE is low?  That's normally how OE works on a part, but the datasheets says the outputs just go low.

CY29942AXI has been EOL. Kindly recommend a drop in replacement part.

Can the following frequencies be output simultaneously with CY 22392.

  18.5035MHz or 27.4405MHz (Output with exclusive use)

  48MHz

  33.333MHz

  20MHz

If output is possible, please tell me the setting contents and calculation formula for CY 22392

I need example code how to program the CY29421FLXI to an arbitrary output frequency. This runs in an embedded system without the ClockWizard software for PC. Here's what I have in mind:

void program_CY29421FLXI(double frequency)

{

    unsigned char DIVO_FS0;

    unsigned char DIVN_INT_FS0;

    unsigned char DIVO_MISC_FS0;

    unsigned char DIVN_FRAC0_FS0;

    unsigned char DIVN_FRAC1_FS0;

    unsigned char DIVN_FRAC2_FS0;

    // Calculate parameters

    // TODO...

    // Program via I2C

    i2c_write(0x55, 0x10, DIVO_FS0);

    i2c_write(0x55, 0x11, DIVN_INT_FS0);

    i2c_write(0x55, 0x12, DIVO_MISC_FS0);

    i2c_write(0x55, 0x13, DIVN_FRAC0_FS0);

    i2c_write(0x55, 0x14, DIVN_FRAC1_FS0);

    i2c_write(0x55, 0x15, DIVN_FRAC2_FS0);

    // Wait until large frequency change is active.

}

It must be possible to change the output frequency an unlimited number of times without power-cycling.

Dear Cypress

Hello.

please let me know if cypress has alternative parts for 7152A-11 and 7152-01 of IDT.

i would be happy if you attached spec comparison table.

thanks

kimura