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CY25100
Document #: 38-07499 Rev. *D Page 3 of 11
Programming Description
Field-Programmable CY25100
The CY25100 is programmed at the package level, i.e., in a
programmer socket. The CY25100 is flash-technology based,
so the parts can be reprogrammed up to 100 times. This allows
for fast and easy design changes and product updates, and
eliminates any issues with old and out-of-date inventory.
Samples and small prototype quantities can be programmed
on the CY3672 programmer with CY3690 (TSSOP) or
CY3691 (SOIC) socket adapter.
CyberClocks Online Software
CyberClocks Online Software is a web-based software appli-
cation that allows the user to custom-configure the CY25100.
All the parameters in Tab l e 1 given as “Enter Data” can be
programmed into the CY25100. CyberClocks Online outputs
an industry-standard JEDEC file used for programming the
CY25100. CyberClocksOnline is available at www.cyberclock-
sonline.com website through user registration. To register,
fillout the registration form and make sure to check the
“non-standard devices” box. For more information on the
registration process refer to CY3672 datasheet
For information regarding Spread Spectrum software
programming solutions, please contact your local Cypress
Sales or Field Application Engineer (FAE), representative for
details.
CY3672 FTG Programming Kit and CY3690/CY3691 Socket
Adapter
The Cypress CY3672 FTG programmer and CY3690/CY3691
Socket Adapter are needed to program the CY25100. The
CY3690 enables user to program CY25100ZCF and
CY25100ZIF (TSSOP) and CY3691 gives the user the ability
to program CY25100SCF and CY25100SIF (SOIC). Each
socket adapter comes with small prototype quantities of
CY25100. The CY3690/CY3691 is a separate orderable item,
so the existing users of the CY3672 FTG development kit or
CY3672-PRG programmer need to order only the socket
adapters to program the CY25100.
Factory-Programmable CY25100
Factory programming is available for volume manufacturing by
Cypress. All requests must be submitted to the local Cypress
Field Application Engineer (FAE) or sales representative. A
sample request form (refer to “CY25100 Sample Request
Form” at www.cypress.com) must be completed. Once the
request has been processed, you will receive a new part
number, samples, and data sheet with the programmed
values. This part number will be used for additional sample
requests and production orders.
Additional information on the CY25100 can be obtained from
the Cypress web site at www.cypress.com.
Product Functions
Input Frequency (XIN, pin 3 and XOUT
,
pin 2)
The input to the CY25100 can be a crystal or a clock. The input
frequency range for crystals is 8 to 30 MHz, and for clock
signals is 8 to 166 MHz.
C
XIN
and C
XOUT
(pin 3 and pin 2)
The load capacitors at Pin 1 (C
XIN
) and Pin 8 (C
XOUT
) can be
programmed from 12 pF to 60 pF with 0.5-pF increments. The
programmed value of these on-chip crystal load capacitors are
the same (XIN = XOUT = 12 to 60 pF).
The required values of C
XIN
and C
XOUT
can be calculated
using the following formula:
C
XIN
= C
XOUT
= 2C
L
– C
P
where C
L
is the crystal load capacitor as specified by the
crystal manufacturer and C
P
is the parasitic PCB capacitance.
For example, if a fundamental 16-MHz crystal with C
L
of 16-pF
is used and C
P
is 2 pF, C
XIN
and C
XOUT
can be calculated as:
C
XIN
= C
XOUT
= (2 x 16) – 2 = 30 pF.
If using a driven reference, set C
XIN
and
C
XOUT
to the
minimum value 12 pF.
Output Frequency, SSCLK Output (SSCLK, pin 7)
The modulated frequency at the SSCLK output is produced by
synthesizing the input reference clock. The modulation can be
stopped by SSON# digital control input (SSON# = HIGH, no
modulation). If modulation is stopped, the clock frequency is
the nominal value of the synthesized frequency without
modulation (spread % = 0). The range of synthesized clock is
from 3–200 MHz.
Spread Percentage (SSCLK, pin 7)
The SSCLK spread can be programmed at any percentage
value from ±0.25% to ±2.5% for Center Spread and from
–0.5% to –5.0% Down Spread.
Reference Output (REFOUT, pin 6)
The reference clock output has the same frequency and the
same phase as the input clock. This output can be
programmed to be enabled (clock on) or disabled (High-Z,
clock off). If this output is not needed, it is recommended that
users request the disabled (High-Z, Clock Off) option.
Frequency Modulation
The frequency modulation is programmed at 31.5 kHz for all
SSCLK frequencies from 3 to 200 MHz. Contact the factory if
a higher-modulation frequency is required.
Power-down or Output Enable (PD# or OE, pin 4):
The part can be programmed to include either PD# or OE
function. PD# function powers down the oscillator and PLL.
The OE function disables the outputs.