CDCE6214-Q1: output clock from OUT0 without I2C setting , with EEPROM default setting

Ray Vincent Aranzaso

Part Number: CDCE6214-Q1
Other Parts Discussed in Thread: CDCE6214

Hi,

I have a customer who has a query with regards with CDCE6214-Q1. Please see below the query of the customer for your reference.

I would like to make CDCE6214-Q1 output clock from OUT0 without I2C setting , with EEPROM default setting. would it be possible?

Both prefef and secref are input clock source.

we made board with CDCE6214-Q1 and CPU. that CPU's reference input is from CDCE6214-Q1.

but when running the board, CDCE6214-Q1 OUT0 output nothing.

CDCE6214-Q1's I2C is controlled by the CPU.

I mean that output0 output "L" all the way.

I expect that PRIREF or SECREF source is bypassed to ouput0 pin7 directly.

I hope you could help us with customer's query. Thank you very much for your support.

Best Regards,

Ray Vincent

over 4 years ago

0 Hao Z over 4 years ago

TI__Mastermind 18070 points

Hi Ray,

By default OUT0 is not enabled. This bit needs to be set to 1 for there to be any output on OUT0.

Regards,
Hao

0 Ray Vincent Aranzaso over 4 years ago in reply to Hao Z

TI__Mastermind 18180 points

Hi Hao,

Thanks for this solution. It really helpful a lot.

By the way, customer have another question.

In Fall-back mode, Which clock (PRIREF,SCREF) is selected as OUT0 after power ON reset?

I hope you can help us again with this query.

Thank you very much for your continuous support.

Best Regards,

Ray Vincent

0 Hao Z over 4 years ago in reply to Ray Vincent Aranzaso

TI__Mastermind 18070 points

Hi Ray,

In the fall back mode, this register is set to "pin select", meaning that it depends on the pin status of REFSEL. If REFSEL is low then SECREF is selected. If it's high then PRIREF.

Regards,
Hao

0 Ray Vincent Aranzaso over 4 years ago in reply to Hao Z

TI__Mastermind 18180 points

Hi Hao,

Please help to confirm if our customer set-up for fallback mode is correct.

To enter "fall back mode", it needs that both "REFSEL" and "HW_SW_CTL" must be float. in that case, REFSEL voltage may be around 1.65V. Because Vih min is 3.3Vx0.8= 2.64v, is CDCE6214 going to take "REFSEL" as "L"?

Thanks again for your continuous support.

Best Regards,

Ray Vincent

0 Hao Z over 4 years ago in reply to Ray Vincent Aranzaso

TI__Mastermind 18070 points

Hi Ray,

Yes you can simply float the two pins. There's also max value for VIL so 1.65V won't be a LOW.

Regards,
Hao

0 Ray Vincent Aranzaso over 4 years ago in reply to Hao Z

TI__Mastermind 18180 points

Hi Hao,

Customer wants to confirm something, please see below for his latest query. Thanks.

When entering fall-back mode by simply floating two pins, is CDCE6214 going to take "REFSEL" as "H"?

Best Regards,

Ray Vincent

0 Hao Z over 4 years ago in reply to Ray Vincent Aranzaso

TI__Mastermind 18070 points

No when the two pins are floating, both pins will be taken as mid-level. These are tri-state pins.

Regards,

Hao

0 Ray Vincent Aranzaso over 4 years ago in reply to Hao Z

TI__Mastermind 18180 points

Hi Hao,

When REFSEL is mid-level, which PRIREF or SECREF is selected as OUT0?

Otherwise, it's uncertain which is selected.

Best Regards,

Ray Vincent

0 Hao Z over 4 years ago in reply to Ray Vincent Aranzaso

TI__Mastermind 18070 points

Hi Ray,

The REFSEL shouldn't be left floating unless 1) EEPROMSEL is also floating. In this case the device enters fall-back mode where SECREF is used. 2) The PRIREF/SECREF is selected through software (see below). In this case the REFSEL level is ignored.

Regards,
Hao

Clock & timing

Clock & timing forum

CDCE6214-Q1: output clock from OUT0 without I2C setting , with EEPROM default setting