CY2XF33

Document Number: 001-53148 Rev. *E

Page 3 of 12

Functional Description

The FS0 and FS1 pins select between four different output

frequencies, as shown in Table 3. Frequency margining is a

common application for this feature. One frequency is used for

the standard operating mode of the device, while the other

frequencies are available for margin testing, either during

product development or in system manufacturing test.

When changing the output frequency, the frequency transition is

not guaranteed to be smooth. There can be frequency

excursions beyond the start frequency and the new frequency.

Glitches and runt pulses are possible, and time must be allowed

for the PLL to relock.

Programming Description

The CY2XF33 is a programmable device. Before being used in

an application, it must be programmed with the output

frequencies and other variables described in a later section. Two

different device types are available, each with its own

programming flow. They are described in the following sections.5

Field Programmable CY2XF33F

Field programmable devices are shipped unprogrammed and

must be programmed before being installed on a printed circuit

board (PCB). Customers use CyberClocks™ Online Software to

specify the device configuration and generate a JEDEC

(extension .jed) programming file. Programming of samples and

prototype quantities is available using a Cypress programmer.

Third party vendors manufacture programmers for small to large

volume applications. Cypress’s value added distribution partners

also provide programming services. Field programmable

devices are designated with an “F” in the part number. They are

intended for quick prototyping and inventory reduction. The

CY2XF33 is one time programmable (OTP).

The software is located at CyberClocks(TM) Online Software.

Factory Configured CY2XF33

For customers wanting ready-to-use devices, the CY2XF33 is

available with no field programming required. All requests are

submitted to the local Cypress Field Application Engineer (FAE)

or sales representative. After the request is processed, the user

receives a new part number, samples, and data sheet with the

programmed values. This part number is used for additional

sample requests and production orders.

Table 2. Frequency Select

FS1

FS0

Output Frequency

0

0

Frequency 0

0

1

Frequency 1

1

0

Frequency 2

1

1

Frequency 3