Electronic Components Datasheet Search
  English  ▼
ALLDATASHEET.COM

X  

CY7B991-7JI Datasheet(PDF) 2 Page - Cypress Semiconductor

Part # CY7B991-7JI
Description  Programmable Skew Clock Buffer
Download  15 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Manufacturer  CYPRESS [Cypress Semiconductor]
Direct Link  http://www.cypress.com
Logo CYPRESS - Cypress Semiconductor

CY7B991-7JI Datasheet(HTML) 2 Page - Cypress Semiconductor

  CY7B991-7JI Datasheet HTML 1Page - Cypress Semiconductor CY7B991-7JI Datasheet HTML 2Page - Cypress Semiconductor CY7B991-7JI Datasheet HTML 3Page - Cypress Semiconductor CY7B991-7JI Datasheet HTML 4Page - Cypress Semiconductor CY7B991-7JI Datasheet HTML 5Page - Cypress Semiconductor CY7B991-7JI Datasheet HTML 6Page - Cypress Semiconductor CY7B991-7JI Datasheet HTML 7Page - Cypress Semiconductor CY7B991-7JI Datasheet HTML 8Page - Cypress Semiconductor CY7B991-7JI Datasheet HTML 9Page - Cypress Semiconductor Next Button
Zoom Inzoom in Zoom Outzoom out
 2 / 15 page
background image
CY7B991
CY7B992
Document #: 38-07138 Rev. **
Page 2 of 15
Block Diagram Description
Phase Frequency Detector and Filter
These two blocks accept inputs from the reference frequency
(REF) input and the feedback (FB) input and generate correc-
tion information to control the frequency of the Voltage-Con-
trolled Oscillator (VCO). These blocks, along with the VCO,
form a Phase-Locked Loop (PLL) that tracks the incoming
REF signal.
VCO and Time Unit Generator
The VCO accepts analog control inputs from the PLL filter
block and generates a frequency that is used by the time unit
generator to create discrete time units that are selected in the
skew select matrix. The operational range of the VCO is de-
termined by the FS control pin. The time unit (tU) is determined
by the operating frequency of the device and the level of the
FS pin as shown in Table 1.
Skew Select Matrix
The skew select matrix is comprised of four independent sec-
tions. Each section has two low-skew, high-fanout drivers
(xQ0, xQ1), and two corresponding three-level function select
(xF0, xF1) inputs. Table 2 below shows the nine possible out-
put functions for each section as determined by the function
select inputs. All times are measured with respect to the REF
input assuming that the output connected to the FB input has
0tU selected.
Pin Definitions
Signal
Name
I/O
Description
REF
I
Reference frequency input. This input supplies the frequency and timing against which all functional
variation is measured.
FB
I
PLL feedback input (typically connected to one of the eight outputs).
FS
I
Three-level frequency range select. See Table 1.
1F0, 1F1
I
Three-level function select inputs for output pair 1 (1Q0, 1Q1). See Table 2.
2F0, 2F1
I
Three-level function select inputs for output pair 2 (2Q0, 2Q1). See Table 2.
3F0, 3F1
I
Three-level function select inputs for output pair 3 (3Q0, 3Q1). See Table 2.
4F0, 4F1
I
Three-level function select inputs for output pair 4 (4Q0, 4Q1). See Table 2.
TEST
I
Three-level select. See test mode section under the block diagram descriptions.
1Q0, 1Q1
O
Output pair 1. See Table 2.
2Q0, 2Q1
O
Output pair 2. See Table 2.
3Q0, 3Q1
O
Output pair 3. See Table 2.
4Q0, 4Q1
O
Output pair 4. See Table 2.
VCCN
PWR
Power supply for output drivers.
VCCQ
PWR
Power supply for internal circuitry.
GND
PWR
Ground.
Table 1. Frequency Range Select and tU Calculation
[1]
FS[2, 3]
fNOM (MHz)
where N =
Approximate
Frequency (MHz) At
Which tU = 1.0 ns
Min.
Max.
LOW
15
30
44
22.7
MID
25
50
26
38.5
HIGH
40
80
16
62.5
t
U
1
f
NOM
N
×
------------------------
=
Table 2. Programmable Skew Configurations[1]
Function Selects
Output Functions
1F1, 2F1,
3F1, 4F1
1F0, 2F0,
3F0, 4F0
1Q0, 1Q1,
2Q0, 2Q1
3Q0, 3Q1
4Q0, 4Q1
LOW
LOW
–4tU
Divide by 2 Divide by 2
LOW
MID
–3tU
–6tU
–6tU
LOW
HIGH
–2tU
–4tU
–4tU
MID
LOW
–1tU
–2tU
–2tU
MID
MID
0tU
0tU
0tU
MID
HIGH
+1tU
+2tU
+2tU
HIGH
LOW
+2tU
+4tU
+4tU
HIGH
MID
+3tU
+6tU
+6tU
HIGH
HIGH
+4tU
Divide by 4
Inverted
Notes:
1.
For all three-state inputs, HIGH indicates a connection to VCC, LOW
indicates a connection to GND, and MID indicates an open connection.
Internal termination circuitry holds an unconnected input to VCC/2.
2.
The level to be set on FS is determined by the “normal” operating fre-
quency (fNOM) of the VCO and Time Unit Generator (see Logic Block
Diagram). Nominal frequency (fNOM) always appears at 1Q0 and the
other outputs when they are operated in their undivided modes (see
Table 2). The frequency appearing at the REF and FB inputs will be fNOM
when the output connected to FB is undivided. The frequency of the REF
and FB inputs will be fNOM/2 or fNOM/4 when the part is configured for a
frequency multiplication by using a divided output as the FB input.
3.
When the FS pin is selected HIGH, the REF input must not transition
upon power-up until VCC has reached 4.3V.


Similar Part No. - CY7B991-7JI

ManufacturerPart #DatasheetDescription
logo
Cypress Semiconductor
CY7B991-7JI CYPRESS-CY7B991-7JI Datasheet
515Kb / 19P
   Programmable Skew Clock Buffer
More results

Similar Description - CY7B991-7JI

ManufacturerPart #DatasheetDescription
logo
Cypress Semiconductor
CY7B991.2JC CYPRESS-CY7B991.2JC Datasheet
519Kb / 19P
   Programmable Skew Clock Buffer
CY7B9911 CYPRESS-CY7B9911_07 Datasheet
392Kb / 13P
   Programmable Skew Clock Buffer
CY7B991 CYPRESS-CY7B991_07 Datasheet
515Kb / 19P
   Programmable Skew Clock Buffer
CY7B991 CYPRESS-CY7B991_11 Datasheet
520Kb / 21P
   Programmable Skew Clock Buffer
CY7B9911 CYPRESS-CY7B9911_08 Datasheet
491Kb / 13P
   Programmable Skew Clock Buffer
logo
Exar Corporation
XRK4993 EXAR-XRK4993 Datasheet
268Kb / 13P
   3.3V PROGRAMMABLE SKEW CLOCK BUFFER
logo
Cypress Semiconductor
CY7B9911 CYPRESS-CY7B9911 Datasheet
244Kb / 12P
   Programmable Skew Clock Buffer (PSCB)
logo
Maxwell Technologies
7B991 MAXWELL-7B991 Datasheet
253Kb / 17P
   Programmable Skew Clock Buffer (PSCB)
logo
Cypress Semiconductor
CY7C9915 CYPRESS-CY7C9915 Datasheet
309Kb / 14P
   3.3V Programmable Skew Clock Buffer
CY7B991V CYPRESS-CY7B991V Datasheet
528Kb / 13P
   Low Voltage Programmable Skew Clock Buffer
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15


Datasheet Download

Go To PDF Page


Link URL




Privacy Policy
ALLDATASHEET.COM
Does ALLDATASHEET help your business so far?  [ DONATE ] 

About Alldatasheet   |   Advertisement   |   Datasheet Upload   |   Contact us   |   Privacy Policy   |   Link Exchange   |   Manufacturer List
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz
Family Site : ic2ic.com  |   icmetro.com