Document #: 38-07644 Rev. *C Page 7 of 15
Field Programming the CY23FP12-002
The CY23FP12-002 comes pre-programmed and ready for use,
but it can also be reprogrammed to any other valid configu ration.
When programming, it must be programmed in a device
programmer prior to being installed in a circuit. The
CY23FP12-002 is based on flash technology, so it can be
reprogrammed up to 100 times. This enables fast and easy
design changes and product updates, and eliminates any issues
with old an d ou t - of-date inven t o r y.
Samples and small prototype quantities can be programmed on
the CY3672-USB programmer. Cypress’s value-added
distribution partners and thi rd-party programming systems from
BP Microsystems, HiLo Systems, and others are available for
large production quantities.
CyberClocks Software
CyberClocks is an easy-to-use software application that allows
the user to custom-configure the CY23FP12-002. Users can
specify the REF, PLL frequency, output frequencies and/or
post-dividers, and different functional options. CyberClocks
outputs an industry standard JEDEC file used for programming
the CY23FP12-002.
CyberClocks can be downloaded free of charge from the
Cypress website at www.cypress.com.
CY3672-USB Development Kit
The Cypress CY3672-USB Developer Kit, in combination with
the CY3692 Socket Adapter, is used to program samples and
small prototype quantities of the CY23FP12-002. This portable
programmer connects to a PC through a USB interface.
The JEDEC file output of CyberClocks can be downloaded to the
portable programmer for small-volume programming, or for use
with a production programming system for larger volumes.
CY23FP12-002 Frequency Calculation
The CY23FP12-002 is an extremely flexible clock buffer with up
to 12 individual outputs, generated from an integrated PLL. Four
variables are used to determine the final output frequency . These
are the input reference frequency, the M and N dividers, and the
post divider.
The basic PLL block diagram is shown in Figure 2 on page 4.
Each of the six clock output pairs has many post divider options
available to it. X is a programmable value between 5 and 130,
and 2X is twice that value. There are six post divider options: /1,
/2, /3, /4, /X, and /2X. The post divider options can be applied to
the calculated PLL frequency or to the REF directly. The
feedback is connected either internally to CLKA0 or externally to
any output.
A programmable divider, M, is inserted between the reference
input, REF, and the phase detector. The divider M can be any
integer 1 to 256. The PLL inp ut frequency cannot be lowe r than
10 MHz or higher than 20 0 MHz. A programma ble divider, N, is
inserted between the feedback input, FBK, and the phase
detector. The divider N can be any integer 1 to 256. The PLL
input frequency cannot be lower than 10 MHz or higher than
200 MHz.
The output can be cal c u l at ed as follows:
FREF / M = FFBK / N.
FPLL = (FREF * N * post divide r) / M.
FOUT = FPLL / post divider.
In addition to above divider options, another option bypasses the
PLL and passes the REF directly to the output.
FOUT = FREF.