
CY2907
Document #: 38-07137 Rev. **
Page 2 of 10
Functional Description
The CY2907 is a general-purpose Clock Generator designed
for use in a wide variety of applications—from graphics to PC
peripherals to disk drives. It generates selectable system clock
frequencies from a single reference input (crystal or reference
clock). The CY2907 is configured with an EPROM array, much
like the other devices in the Cypress EPROM Programmable
Clock Family, making it easily customizable for any applica-
tion. Furthermore, the CY2907 is compatible with all indus-
try-standard 9107 and 9108 clock synthesizers.
CyClocks™ Software
CyClocks is an easy-to-use software application that allows
you to configure any one of the EPROM Programmable Clocks
offered by Cypress. You may specify the input frequency, PLL
and output frequencies, and different functional options.
Please note the output frequency ranges in this data sheet
when specifying them in CyClocks to ensure that you stay
within the limits. You can download a copy of CyClocks free on
the Cypress Semiconductor website at www.cypress.com.
Consider using the CY2081, CY2291, or CY2292 for applica-
tions that require unrelated and multiple output frequencies.
Consider using the CY2071A for applications that require
more than one output clock.
Cypress FTG Programmer
The Cypress Frequency Timing Generator (FTG) Program-
mers are portable programmers designed to custom program
our family of EPROM Field Programmable Clock Devices.
The FTG programmers connect to a PC serial port and allow
users of CyClocks software to quickly and easily program any
of the CY2291F, CY2292F, CY2071AF, and CY2907F devices.
The ordering code for the Cypress FTG Programmer is
CY3670.
Maximum Ratings
(Beyond which the useful life may be impaired. For user guide-
lines, not tested.)
Supply Voltage ................................................. –0.5 to +7.0V
Input Voltage ........................................... –0.5V to VDD+0.5V
Storage Temperature (Non-Condensing) ... –65°C to +150°C
Max. Soldering Temperature (10 sec) ...................... +260°C
Junction Temperature ............................................... +150°C
Static Discharge Voltage ........................................... >2000V
(per MIL-STD-883, Method 3015)
Pin Summary
Name
Pin Number
Description
14-Pin SOIC
8-Pin SOIC
S1
1
5
Frequency Select (CLKA) (Internal pull-up resistor to VDD)
S2
2
NA
Frequency Select (CLKA) (Internal pull-up resistor to VDD)
S3
3
NA
Frequency Select (CLKA) (Internal pull-up resistor to VDD)
VSS
4
2
Ground
VSS
5
NA
Ground
PD
6
NA
Power-Down (active LOW) (Internal pull-up resistor to VDD)
XTALIN[1]
7
3
Reference Crystal Input
XTALOUT[1, 2]
8
4
Reference Crystal Feedback
OER
9
NA
REFCLK Output Enable (active HIGH) (Internal pull-up resistor to VDD)
OEA
10
NA
CLKA Output Enable (active HIGH) (Internal pull-up resistor to VDD)
CLKA
11
6
Clock Output
VDD
12
7
Voltage Supply
REFCLK
13
8
Reference Clock Output (Default, can be driven by PLL if desired)
S0
14
1
Frequency Select (CLKA) (Internal pull-up resistor to VDD)
Notes:
1.
For best accuracy, use a parallel-resonant crystal, CLOAD ≈ 17 pF.
2.
Float XTALOUT pin if XTALIN is driven by reference clock (as opposed to crystal).